pax_global_header00006660000000000000000000000064126167571710014527gustar00rootroot0000000000000052 comment=93099f38de7421e6979983652730a81e2bafd578 libkv-0.1.0/000077500000000000000000000000001261675717100126345ustar00rootroot00000000000000libkv-0.1.0/.travis.yml000066400000000000000000000022251261675717100147460ustar00rootroot00000000000000language: go go: - 1.3 # - 1.4 # see https://github.com/moovweb/gvm/pull/116 for why Go 1.4 is currently disabled # let us have speedy Docker-based Travis workers sudo: false before_install: # Symlink below is needed for Travis CI to work correctly on personal forks of libkv - ln -s $HOME/gopath/src/github.com/${TRAVIS_REPO_SLUG///libkv/} $HOME/gopath/src/github.com/docker - go get golang.org/x/tools/cmd/vet - go get golang.org/x/tools/cmd/cover - go get github.com/mattn/goveralls - go get github.com/golang/lint/golint - go get github.com/GeertJohan/fgt before_script: - script/travis_consul.sh 0.5.2 - script/travis_etcd.sh 2.2.0 - script/travis_zk.sh 3.4.6 script: - ./consul agent -server -bootstrap-expect 1 -data-dir /tmp/consul -config-file=./config.json 1>/dev/null & - ./etcd/etcd --listen-client-urls 'http://0.0.0.0:4001' --advertise-client-urls 'http://127.0.0.1:4001' >/dev/null 2>&1 & - ./zk/bin/zkServer.sh start ./zk/conf/zoo.cfg 1> /dev/null - script/validate-gofmt - go vet ./... - fgt golint ./... - go test -v -race ./... - script/coverage - goveralls -service=travis-ci -coverprofile=goverage.report libkv-0.1.0/LICENSE.code000066400000000000000000000250131261675717100145530ustar00rootroot00000000000000 Apache License Version 2.0, January 2004 http://www.apache.org/licenses/ TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION 1. 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Creative Commons may be contacted at creativecommons.org. libkv-0.1.0/README.md000066400000000000000000000137601261675717100141220ustar00rootroot00000000000000# libkv [![GoDoc](https://godoc.org/github.com/docker/libkv?status.png)](https://godoc.org/github.com/docker/libkv) [![Build Status](https://travis-ci.org/docker/libkv.svg?branch=master)](https://travis-ci.org/docker/libkv) [![Coverage Status](https://coveralls.io/repos/docker/libkv/badge.svg)](https://coveralls.io/r/docker/libkv) `libkv` provides a `Go` native library to store metadata. The goal of `libkv` is to abstract common store operations for multiple distributed and/or local Key/Value store backends. For example, you can use it to store your metadata or for service discovery to register machines and endpoints inside your cluster. You can also easily implement a generic *Leader Election* on top of it (see the [swarm/leadership](https://github.com/docker/swarm/tree/master/leadership) package). As of now, `libkv` offers support for `Consul`, `Etcd`, `Zookeeper` (**Distributed** store) and `BoltDB` (**Local** store). ## Usage `libkv` is meant to be used as an abstraction layer over existing distributed Key/Value stores. It is especially useful if you plan to support `consul`, `etcd` and `zookeeper` using the same codebase. It is ideal if you plan for something written in Go that should support: - A simple metadata storage, distributed or local - A lightweight discovery service for your nodes - A distributed lock mechanism You can find examples of usage for `libkv` under in `docs/examples.go`. Optionally you can also take a look at the `docker/swarm` or `docker/libnetwork` repositories which are using `docker/libkv` for all the use cases listed above. ## Supported versions `libkv` supports: - Consul versions >= `0.5.1` because it uses Sessions with `Delete` behavior for the use of `TTLs` (mimics zookeeper's Ephemeral node support), If you don't plan to use `TTLs`: you can use Consul version `0.4.0+`. - Etcd versions >= `2.0` because it uses the new `coreos/etcd/client`, this might change in the future as the support for `APIv3` comes along and adds mor capabilities. - Zookeeper versions >= `3.4.5`. Although this might work with previous version but this remains untested as of now. - Boltdb, which shouldn't be subject to any version dependencies. ## Interface A **storage backend** in `libkv` should implement (fully or partially) this interface: ```go type Store interface { Put(key string, value []byte, options *WriteOptions) error Get(key string) (*KVPair, error) Delete(key string) error Exists(key string) (bool, error) Watch(key string, stopCh <-chan struct{}) (<-chan *KVPair, error) WatchTree(directory string, stopCh <-chan struct{}) (<-chan []*KVPair, error) NewLock(key string, options *LockOptions) (Locker, error) List(directory string) ([]*KVPair, error) DeleteTree(directory string) error AtomicPut(key string, value []byte, previous *KVPair, options *WriteOptions) (bool, *KVPair, error) AtomicDelete(key string, previous *KVPair) (bool, error) Close() } ``` ## Compatibility matrix Backend drivers in `libkv` are generally divided between **local drivers** and **distributed drivers**. Distributed backends offer enhanced capabilities like `Watches` and/or distributed `Locks`. Local drivers are usually used in complement to the distributed drivers to store informations that only needs to be available locally. | Calls | Consul | Etcd | Zookeeper | BoltDB | |-----------------------|:----------:|:------:|:-----------:|:--------:| | Put | X | X | X | X | | Get | X | X | X | X | | Delete | X | X | X | X | | Exists | X | X | X | X | | Watch | X | X | X | | | WatchTree | X | X | X | | | NewLock (Lock/Unlock) | X | X | X | | | List | X | X | X | X | | DeleteTree | X | X | X | X | | AtomicPut | X | X | X | X | | Close | X | X | X | X | ## Limitations Distributed Key/Value stores often have different concepts for managing and formatting keys and their associated values. Even though `libkv` tries to abstract those stores aiming for some consistency, in some cases it can't be applied easily. Please refer to the `docs/compatibility.md` to see what are the special cases for cross-backend compatibility. Other than those special cases, you should expect the same experience for basic operations like `Get`/`Put`, etc. Calls like `WatchTree` may return different events (or number of events) depending on the backend (for now, `Etcd` and `Consul` will likely return more events than `Zookeeper` that you should triage properly). Although you should be able to use it successfully to watch on events in an interchangeable way (see the **swarm/leadership** or **swarm/discovery** packages in **docker/swarm**). ## TLS Only `Consul` and `etcd` have support for TLS and you should build and provide your own `config.TLS` object to feed the client. Support is planned for `zookeeper`. ##Roadmap - Make the API nicer to use (using `options`) - Provide more options (`consistency` for example) - Improve performance (remove extras `Get`/`List` operations) - Better key formatting - New backends? ##Contributing Want to hack on libkv? [Docker's contributions guidelines](https://github.com/docker/docker/blob/master/CONTRIBUTING.md) apply. ##Copyright and license Copyright © 2014-2015 Docker, Inc. All rights reserved, except as follows. Code is released under the Apache 2.0 license. The README.md file, and files in the "docs" folder are licensed under the Creative Commons Attribution 4.0 International License under the terms and conditions set forth in the file "LICENSE.docs". You may obtain a duplicate copy of the same license, titled CC-BY-SA-4.0, at http://creativecommons.org/licenses/by/4.0/. libkv-0.1.0/docs/000077500000000000000000000000001261675717100135645ustar00rootroot00000000000000libkv-0.1.0/docs/compatibility.md000066400000000000000000000113051261675717100167570ustar00rootroot00000000000000#Cross-Backend Compatibility The value of `libkv` is not to duplicate the code for programs that should support multiple distributed K/V stores like the classic `Consul`/`etcd`/`zookeeper` trio. This document provides with general guidelines for users willing to support those backends with the same code using `libkv`. Please note that most of those workarounds are going to disappear in the future with `etcd` APIv3. ##Etcd directory/key distinction `etcd` with APIv2 makes the distinction between keys and directories. The result with `libkv` is that when using the etcd driver: - You cannot store values on directories - You cannot invoke `WatchTree` (watching on child values), on a regular key This is fundamentaly different than `Consul` and `zookeeper` which are more permissive and allow the same set of operations on keys and directories (called a Node for zookeeper). Apiv3 is in the work for `etcd`, which removes this key/directory distinction, but until then you should follow these workarounds to make your `libkv` code work across backends. ###Put `etcd` cannot put values on directories, so this puts a major restriction compared to `Consul` and `zookeeper`. If you want to support all those three backends, you should make sure to only put data on **leaves**. For example: ```go _ := kv.Put("path/to/key/bis", []byte("foo"), nil) _ := kv.Put("path/to/key", []byte("bar"), nil) ``` Will work on `Consul` and `zookeeper` but fail for `etcd`. This is because the first `Put` in the case of `etcd` will recursively create the directory hierarchy and `path/to/key` is now considered as a directory. Thus, values should always be stored on leaves if the support for the three backends is planned. ###WatchTree When initializing the `WatchTree`, the natural way to do so is through the following code: ```go key := "path/to/key" if !kv.Exists(key) { err := kv.Put(key, []byte("data"), nil) } events, err := kv.WatchTree(key, nil) ``` The code above will not work across backends and etcd will fail on the `WatchTree` call. What happens exactly: - `Consul` will create a regular `key` because it has no distinction between directories and keys. This is not an issue as we can invoke `WatchTree` on regular keys. - `zookeeper` is going to create a `node` that can either be a directory or a key during the lifetime of a program but it does not matter as a directory can hold values and be watchable like a regular key. - `etcd` is going to create a regular `key`. We cannot invoke `WatchTree` on regular keys using etcd. To be cross-compatible between those three backends for `WatchTree`, we need to enforce a parameter that is only interpreted with `etcd` and which tells the client to create a `directory` instead of a key. ```go key := "path/to/key" if !kv.Exists(key) { // We enforce IsDir = true to make sure etcd creates a directory err := kv.Put(key, []byte("data"), &store.WriteOptions{IsDir:true}) } events, err := kv.WatchTree(key, nil) ``` The code above will work for the three backends but make sure to not try to store any value at that path as the call to `Put` will fail for `etcd` (you can only put at `path/to/key/foo`, `path/to/key/bar` for example). ##Etcd distributed locking There is `Lock` mechanisms baked in the `coreos/etcd/client` for now. Instead, `libkv` has its own implementation of a `Lock` on top of `etcd`. The general workflow for the `Lock` is as follows: - Call Lock concurrently on a `key` between threads/programs - Only one will create that key, others are going to fail because the key has already been created - The thread locking the key can get the right index to set the value of the key using Compare And Swap and effectively Lock and hold the key - Other threads are given a wrong index to fail the Compare and Swap and block until the key has been released by the thread holding the Lock - Lock seekers are setting up a Watch listening on that key and events happening on the key - When the thread/program stops holding the lock, it deletes the key triggering a `delete` event that will notify all the other threads. In case the program crashes, the key has a TTL attached that will send an `expire` event when this TTL expires. - Once everyone is notified, back to the first step. First come, first served with the Lock. The whole Lock process is highly dependent on the `delete`/`expire` events of `etcd`. So don't expect the key to be still there once the Lock is released. For example if the whole logic is to `Lock` a key and expect the value to still be there after it has been unlocked, it is not going to be cross-backend compatible with `Consul` and `zookeeper`. On the other end the `etcd` Lock can still be used to do Leader Election for example and still be cross-compatible with other backends.libkv-0.1.0/docs/examples.md000066400000000000000000000102111261675717100157170ustar00rootroot00000000000000#Examples This document contains useful example of usage for `libkv`. It might not be complete but provides with general informations on how to use the client. ##Create a store and use Put/Get/Delete ```go package main import ( "fmt" "time" "log" "github.com/docker/libkv" "github.com/docker/libkv/store" "github.com/docker/libkv/store/consul" ) func init() { // Register consul store to libkv consul.Register() // We can register as many backends that are supported by libkv etcd.Register() zookeeper.Register() boltdb.Register() } func main() { client := "localhost:8500" // Initialize a new store with consul kv, err := libkv.NewStore( store.CONSUL, // or "consul" []string{client}, &store.Config{ ConnectionTimeout: 10*time.Second, }, ) if err != nil { log.Fatal("Cannot create store consul") } key := "foo" err = kv.Put(key, []byte("bar"), nil) if err != nil { fmt.Errorf("Error trying to put value at key: %v", key) } pair, err := kv.Get(key) if err != nil { fmt.Errorf("Error trying accessing value at key: %v", key) } err = kv.Delete(key) if err != nil { fmt.Errorf("Error trying to delete key %v", key) } log.Info("value: ", string(pair.Value)) } ``` ##List keys ```go // List will list all the keys under `key` if it contains a set of child keys/values entries, err := kv.List(key) for _, pair := range entries { fmt.Printf("key=%v - value=%v", pair.Key, string(pair.Value)) } ``` ##Watching for events on a single key (Watch) You can use watches to watch modifications on a key. First you need to check if the key exists. If this is not the case, we need to create it using the `Put` function. ```go // Checking on the key before watching if !kv.Exists(key) { err := kv.Put(key, []byte("bar"), nil) if err != nil { fmt.Errorf("Something went wrong when initializing key %v", key) } } stopCh := make(<-chan struct{}) events, err := kv.Watch(key, stopCh) select { case pair := <-events: // Do something with events fmt.Printf("value changed on key %v: new value=%v", key, pair.Value) } ``` ##Watching for events happening on child keys (WatchTree) You can use watches to watch modifications on a key. First you need to check if the key exists. If this is not the case, we need to create it using the `Put` function. There is a special step here though if you want your code to work across backends. Because `etcd` is a special case and it makes the distinction between directories and keys, we need to make sure that the created key is considered as a directory by enforcing `IsDir` at `true`. ```go // Checking on the key before watching if !kv.Exists(key) { // Don't forget IsDir:true if the code is used cross-backend err := kv.Put(key, []byte("bar"), &store.WriteOptions{IsDir:true}) if err != nil { fmt.Errorf("Something went wrong when initializing key %v", key) } } stopCh := make(<-chan struct{}) events, err := kv.WatchTree(key, stopCh) select { case pairs := <-events: // Do something with events for _, pair := range pairs { fmt.Printf("value changed on key %v: new value=%v", key, pair.Value) } } ``` ## Distributed Locking, using Lock/Unlock ```go key := "lockKey" value := []byte("bar") // Initialize a distributed lock. TTL is optional, it is here to make sure that // the lock is released after the program that is holding the lock ends or crashes lock, err := kv.NewLock(key, &store.LockOptions{Value: value, TTL: 2 * time.Second}) if err != nil { fmt.Errorf("something went wrong when trying to initialize the Lock") } // Try to lock the key, the call to Lock() is blocking _, err := lock.Lock(nil) if err != nil { fmt.Errorf("something went wrong when trying to lock key %v", key) } // Get should work because we are holding the key pair, err := kv.Get(key) if err != nil { fmt.Errorf("key %v has value %v", key, pair.Value) } // Unlock the key err = lock.Unlock() if err != nil { fmt.Errorf("something went wrong when trying to unlock key %v", key) } ```libkv-0.1.0/libkv.go000066400000000000000000000017301261675717100142730ustar00rootroot00000000000000package libkv import ( "fmt" "sort" "strings" "github.com/docker/libkv/store" ) // Initialize creates a new Store object, initializing the client type Initialize func(addrs []string, options *store.Config) (store.Store, error) var ( // Backend initializers initializers = make(map[store.Backend]Initialize) supportedBackend = func() string { keys := make([]string, 0, len(initializers)) for k := range initializers { keys = append(keys, string(k)) } sort.Strings(keys) return strings.Join(keys, ", ") }() ) // NewStore creates a an instance of store func NewStore(backend store.Backend, addrs []string, options *store.Config) (store.Store, error) { if init, exists := initializers[backend]; exists { return init(addrs, options) } return nil, fmt.Errorf("%s %s", store.ErrBackendNotSupported.Error(), supportedBackend) } // AddStore adds a new store backend to libkv func AddStore(store store.Backend, init Initialize) { initializers[store] = init } libkv-0.1.0/libkv_test.go000066400000000000000000000007011261675717100153270ustar00rootroot00000000000000package libkv import ( "testing" "time" "github.com/docker/libkv/store" "github.com/stretchr/testify/assert" ) func TestNewStoreUnsupported(t *testing.T) { client := "localhost:9999" kv, err := NewStore( "unsupported", []string{client}, &store.Config{ ConnectionTimeout: 10 * time.Second, }, ) assert.Error(t, err) assert.Nil(t, kv) assert.Equal(t, "Backend storage not supported yet, please choose one of ", err.Error()) } libkv-0.1.0/script/000077500000000000000000000000001261675717100141405ustar00rootroot00000000000000libkv-0.1.0/script/.validate000066400000000000000000000017111261675717100157320ustar00rootroot00000000000000#!/bin/bash if [ -z "$VALIDATE_UPSTREAM" ]; then # this is kind of an expensive check, so let's not do this twice if we # are running more than one validate bundlescript VALIDATE_REPO='https://github.com/docker/libkv.git' VALIDATE_BRANCH='master' if [ "$TRAVIS" = 'true' -a "$TRAVIS_PULL_REQUEST" != 'false' ]; then VALIDATE_REPO="https://github.com/${TRAVIS_REPO_SLUG}.git" VALIDATE_BRANCH="${TRAVIS_BRANCH}" fi VALIDATE_HEAD="$(git rev-parse --verify HEAD)" git fetch -q "$VALIDATE_REPO" "refs/heads/$VALIDATE_BRANCH" VALIDATE_UPSTREAM="$(git rev-parse --verify FETCH_HEAD)" VALIDATE_COMMIT_LOG="$VALIDATE_UPSTREAM..$VALIDATE_HEAD" VALIDATE_COMMIT_DIFF="$VALIDATE_UPSTREAM...$VALIDATE_HEAD" validate_diff() { if [ "$VALIDATE_UPSTREAM" != "$VALIDATE_HEAD" ]; then git diff "$VALIDATE_COMMIT_DIFF" "$@" fi } validate_log() { if [ "$VALIDATE_UPSTREAM" != "$VALIDATE_HEAD" ]; then git log "$VALIDATE_COMMIT_LOG" "$@" fi } fi libkv-0.1.0/script/coverage000077500000000000000000000010251261675717100156570ustar00rootroot00000000000000#!/bin/bash MODE="mode: count" ROOT=${TRAVIS_BUILD_DIR:-.}/../../.. # Grab the list of packages. # Exclude the API and CLI from coverage as it will be covered by integration tests. PACKAGES=`go list ./...` # Create the empty coverage file. echo $MODE > goverage.report # Run coverage on every package. for package in $PACKAGES; do output="$ROOT/$package/coverage.out" go test -test.short -covermode=count -coverprofile=$output $package if [ -f "$output" ] ; then cat "$output" | grep -v "$MODE" >> goverage.report fi done libkv-0.1.0/script/travis_consul.sh000077500000000000000000000005561261675717100174000ustar00rootroot00000000000000#!/bin/bash if [ $# -gt 0 ] ; then CONSUL_VERSION="$1" else CONSUL_VERSION="0.5.2" fi # install consul wget "https://dl.bintray.com/mitchellh/consul/${CONSUL_VERSION}_linux_amd64.zip" unzip "${CONSUL_VERSION}_linux_amd64.zip" # make config for minimum ttl touch config.json echo "{\"session_ttl_min\": \"1s\"}" >> config.json # check ./consul --version libkv-0.1.0/script/travis_etcd.sh000077500000000000000000000005161261675717100170100ustar00rootroot00000000000000#!/bin/bash if [ $# -gt 0 ] ; then ETCD_VERSION="$1" else ETCD_VERSION="2.2.0" fi curl -L https://github.com/coreos/etcd/releases/download/v$ETCD_VERSION/etcd-v$ETCD_VERSION-linux-amd64.tar.gz -o etcd-v$ETCD_VERSION-linux-amd64.tar.gz tar xzvf etcd-v$ETCD_VERSION-linux-amd64.tar.gz mv etcd-v$ETCD_VERSION-linux-amd64 etcd libkv-0.1.0/script/travis_zk.sh000077500000000000000000000004651261675717100165200ustar00rootroot00000000000000#!/bin/bash if [ $# -gt 0 ] ; then ZK_VERSION="$1" else ZK_VERSION="3.4.6" fi wget "http://mirrors.ukfast.co.uk/sites/ftp.apache.org/zookeeper/stable/zookeeper-${ZK_VERSION}.tar.gz" tar -xvf "zookeeper-${ZK_VERSION}.tar.gz" mv zookeeper-$ZK_VERSION zk mv ./zk/conf/zoo_sample.cfg ./zk/conf/zoo.cfg libkv-0.1.0/script/validate-gofmt000077500000000000000000000013101261675717100167640ustar00rootroot00000000000000#!/bin/bash source "$(dirname "$BASH_SOURCE")/.validate" IFS=$'\n' files=( $(validate_diff --diff-filter=ACMR --name-only -- '*.go' | grep -v '^Godeps/' || true) ) unset IFS badFiles=() for f in "${files[@]}"; do # we use "git show" here to validate that what's committed is formatted if [ "$(git show "$VALIDATE_HEAD:$f" | gofmt -s -l)" ]; then badFiles+=( "$f" ) fi done if [ ${#badFiles[@]} -eq 0 ]; then echo 'Congratulations! All Go source files are properly formatted.' else { echo "These files are not properly gofmt'd:" for f in "${badFiles[@]}"; do echo " - $f" done echo echo 'Please reformat the above files using "gofmt -s -w" and commit the result.' echo } >&2 false fi libkv-0.1.0/store/000077500000000000000000000000001261675717100137705ustar00rootroot00000000000000libkv-0.1.0/store/boltdb/000077500000000000000000000000001261675717100152365ustar00rootroot00000000000000libkv-0.1.0/store/boltdb/boltdb.go000066400000000000000000000243301261675717100170350ustar00rootroot00000000000000package boltdb import ( "bytes" "encoding/binary" "errors" "os" "path/filepath" "sync" "sync/atomic" "time" "github.com/boltdb/bolt" "github.com/docker/libkv" "github.com/docker/libkv/store" ) var ( // ErrMultipleEndpointsUnsupported is thrown when multiple endpoints specified for // BoltDB. Endpoint has to be a local file path ErrMultipleEndpointsUnsupported = errors.New("boltdb supports one endpoint and should be a file path") // ErrBoltBucketNotFound is thrown when specified BoltBD bucket doesn't exist in the DB ErrBoltBucketNotFound = errors.New("boltdb bucket doesn't exist") // ErrBoltBucketOptionMissing is thrown when boltBcuket config option is missing ErrBoltBucketOptionMissing = errors.New("boltBucket config option missing") ) const ( filePerm os.FileMode = 0644 ) //BoltDB type implements the Store interface type BoltDB struct { client *bolt.DB boltBucket []byte dbIndex uint64 path string timeout time.Duration // By default libkv opens and closes the bolt DB connection for every // get/put operation. This allows multiple apps to use a Bolt DB at the // same time. // PersistConnection flag provides an option to override ths behavior. // ie: open the connection in New and use it till Close is called. PersistConnection bool sync.Mutex } const ( libkvmetadatalen = 8 transientTimeout = time.Duration(10) * time.Second ) // Register registers boltdb to libkv func Register() { libkv.AddStore(store.BOLTDB, New) } // New opens a new BoltDB connection to the specified path and bucket func New(endpoints []string, options *store.Config) (store.Store, error) { var ( db *bolt.DB err error boltOptions *bolt.Options ) if len(endpoints) > 1 { return nil, ErrMultipleEndpointsUnsupported } if (options == nil) || (len(options.Bucket) == 0) { return nil, ErrBoltBucketOptionMissing } dir, _ := filepath.Split(endpoints[0]) if err = os.MkdirAll(dir, 0750); err != nil { return nil, err } if options.PersistConnection { boltOptions = &bolt.Options{Timeout: options.ConnectionTimeout} db, err = bolt.Open(endpoints[0], filePerm, boltOptions) if err != nil { return nil, err } } b := &BoltDB{ client: db, path: endpoints[0], boltBucket: []byte(options.Bucket), timeout: transientTimeout, PersistConnection: options.PersistConnection, } return b, nil } func (b *BoltDB) reset() { b.path = "" b.boltBucket = []byte{} } func (b *BoltDB) getDBhandle() (*bolt.DB, error) { var ( db *bolt.DB err error ) if !b.PersistConnection { boltOptions := &bolt.Options{Timeout: b.timeout} if db, err = bolt.Open(b.path, filePerm, boltOptions); err != nil { return nil, err } b.client = db } return b.client, nil } func (b *BoltDB) releaseDBhandle() { if !b.PersistConnection { b.client.Close() } } // Get the value at "key". BoltDB doesn't provide an inbuilt last modified index with every kv pair. Its implemented by // by a atomic counter maintained by the libkv and appened to the value passed by the client. func (b *BoltDB) Get(key string) (*store.KVPair, error) { var ( val []byte db *bolt.DB err error ) b.Lock() defer b.Unlock() if db, err = b.getDBhandle(); err != nil { return nil, err } defer b.releaseDBhandle() err = db.View(func(tx *bolt.Tx) error { bucket := tx.Bucket(b.boltBucket) if bucket == nil { return ErrBoltBucketNotFound } v := bucket.Get([]byte(key)) val = make([]byte, len(v)) copy(val, v) return nil }) if len(val) == 0 { return nil, store.ErrKeyNotFound } if err != nil { return nil, err } dbIndex := binary.LittleEndian.Uint64(val[:libkvmetadatalen]) val = val[libkvmetadatalen:] return &store.KVPair{Key: key, Value: val, LastIndex: (dbIndex)}, nil } //Put the key, value pair. index number metadata is prepended to the value func (b *BoltDB) Put(key string, value []byte, opts *store.WriteOptions) error { var ( dbIndex uint64 db *bolt.DB err error ) b.Lock() defer b.Unlock() dbval := make([]byte, libkvmetadatalen) if db, err = b.getDBhandle(); err != nil { return err } defer b.releaseDBhandle() err = db.Update(func(tx *bolt.Tx) error { bucket, err := tx.CreateBucketIfNotExists(b.boltBucket) if err != nil { return err } dbIndex = atomic.AddUint64(&b.dbIndex, 1) binary.LittleEndian.PutUint64(dbval, dbIndex) dbval = append(dbval, value...) err = bucket.Put([]byte(key), dbval) if err != nil { return err } return nil }) return err } //Delete the value for the given key. func (b *BoltDB) Delete(key string) error { var ( db *bolt.DB err error ) b.Lock() defer b.Unlock() if db, err = b.getDBhandle(); err != nil { return err } defer b.releaseDBhandle() err = db.Update(func(tx *bolt.Tx) error { bucket := tx.Bucket(b.boltBucket) if bucket == nil { return ErrBoltBucketNotFound } err := bucket.Delete([]byte(key)) return err }) return err } // Exists checks if the key exists inside the store func (b *BoltDB) Exists(key string) (bool, error) { var ( val []byte db *bolt.DB err error ) b.Lock() defer b.Unlock() if db, err = b.getDBhandle(); err != nil { return false, err } defer b.releaseDBhandle() err = db.View(func(tx *bolt.Tx) error { bucket := tx.Bucket(b.boltBucket) if bucket == nil { return ErrBoltBucketNotFound } val = bucket.Get([]byte(key)) return nil }) if len(val) == 0 { return false, err } return true, err } // List returns the range of keys starting with the passed in prefix func (b *BoltDB) List(keyPrefix string) ([]*store.KVPair, error) { var ( db *bolt.DB err error ) b.Lock() defer b.Unlock() kv := []*store.KVPair{} if db, err = b.getDBhandle(); err != nil { return nil, err } defer b.releaseDBhandle() err = db.View(func(tx *bolt.Tx) error { bucket := tx.Bucket(b.boltBucket) if bucket == nil { return ErrBoltBucketNotFound } cursor := bucket.Cursor() prefix := []byte(keyPrefix) for key, v := cursor.Seek(prefix); bytes.HasPrefix(key, prefix); key, v = cursor.Next() { dbIndex := binary.LittleEndian.Uint64(v[:libkvmetadatalen]) v = v[libkvmetadatalen:] val := make([]byte, len(v)) copy(val, v) kv = append(kv, &store.KVPair{ Key: string(key), Value: val, LastIndex: dbIndex, }) } return nil }) if len(kv) == 0 { return nil, store.ErrKeyNotFound } return kv, err } // AtomicDelete deletes a value at "key" if the key // has not been modified in the meantime, throws an // error if this is the case func (b *BoltDB) AtomicDelete(key string, previous *store.KVPair) (bool, error) { var ( val []byte db *bolt.DB err error ) b.Lock() defer b.Unlock() if previous == nil { return false, store.ErrPreviousNotSpecified } if db, err = b.getDBhandle(); err != nil { return false, err } defer b.releaseDBhandle() err = db.Update(func(tx *bolt.Tx) error { bucket := tx.Bucket(b.boltBucket) if bucket == nil { return ErrBoltBucketNotFound } val = bucket.Get([]byte(key)) if val == nil { return store.ErrKeyNotFound } dbIndex := binary.LittleEndian.Uint64(val[:libkvmetadatalen]) if dbIndex != previous.LastIndex { return store.ErrKeyModified } err := bucket.Delete([]byte(key)) return err }) if err != nil { return false, err } return true, err } // AtomicPut puts a value at "key" if the key has not been // modified since the last Put, throws an error if this is the case func (b *BoltDB) AtomicPut(key string, value []byte, previous *store.KVPair, options *store.WriteOptions) (bool, *store.KVPair, error) { var ( val []byte dbIndex uint64 db *bolt.DB err error ) b.Lock() defer b.Unlock() dbval := make([]byte, libkvmetadatalen) if db, err = b.getDBhandle(); err != nil { return false, nil, err } defer b.releaseDBhandle() err = db.Update(func(tx *bolt.Tx) error { var err error bucket := tx.Bucket(b.boltBucket) if bucket == nil { if previous != nil { return ErrBoltBucketNotFound } bucket, err = tx.CreateBucket(b.boltBucket) if err != nil { return err } } // AtomicPut is equivalent to Put if previous is nil and the Ky // doesn't exist in the DB. val = bucket.Get([]byte(key)) if previous == nil && len(val) != 0 { return store.ErrKeyExists } if previous != nil { if len(val) == 0 { return store.ErrKeyNotFound } dbIndex = binary.LittleEndian.Uint64(val[:libkvmetadatalen]) if dbIndex != previous.LastIndex { return store.ErrKeyModified } } dbIndex = atomic.AddUint64(&b.dbIndex, 1) binary.LittleEndian.PutUint64(dbval, b.dbIndex) dbval = append(dbval, value...) return (bucket.Put([]byte(key), dbval)) }) if err != nil { return false, nil, err } updated := &store.KVPair{ Key: key, Value: value, LastIndex: dbIndex, } return true, updated, nil } // Close the db connection to the BoltDB func (b *BoltDB) Close() { b.Lock() defer b.Unlock() if !b.PersistConnection { b.reset() } else { b.client.Close() } return } // DeleteTree deletes a range of keys with a given prefix func (b *BoltDB) DeleteTree(keyPrefix string) error { var ( db *bolt.DB err error ) b.Lock() defer b.Unlock() if db, err = b.getDBhandle(); err != nil { return err } defer b.releaseDBhandle() err = db.Update(func(tx *bolt.Tx) error { bucket := tx.Bucket(b.boltBucket) if bucket == nil { return ErrBoltBucketNotFound } cursor := bucket.Cursor() prefix := []byte(keyPrefix) for key, _ := cursor.Seek(prefix); bytes.HasPrefix(key, prefix); key, _ = cursor.Next() { _ = bucket.Delete([]byte(key)) } return nil }) return err } // NewLock has to implemented at the library level since its not supported by BoltDB func (b *BoltDB) NewLock(key string, options *store.LockOptions) (store.Locker, error) { return nil, store.ErrCallNotSupported } // Watch has to implemented at the library level since its not supported by BoltDB func (b *BoltDB) Watch(key string, stopCh <-chan struct{}) (<-chan *store.KVPair, error) { return nil, store.ErrCallNotSupported } // WatchTree has to implemented at the library level since its not supported by BoltDB func (b *BoltDB) WatchTree(directory string, stopCh <-chan struct{}) (<-chan []*store.KVPair, error) { return nil, store.ErrCallNotSupported } libkv-0.1.0/store/boltdb/boltdb_test.go000066400000000000000000000064151261675717100201000ustar00rootroot00000000000000package boltdb import ( "os" "testing" "time" "github.com/docker/libkv" "github.com/docker/libkv/store" "github.com/docker/libkv/testutils" "github.com/stretchr/testify/assert" ) func makeBoltDBClient(t *testing.T) store.Store { kv, err := New([]string{"/tmp/not_exist_dir/__boltdbtest"}, &store.Config{Bucket: "boltDBTest"}) if err != nil { t.Fatalf("cannot create store: %v", err) } return kv } func TestRegister(t *testing.T) { Register() kv, err := libkv.NewStore( store.BOLTDB, []string{"/tmp/not_exist_dir/__boltdbtest"}, &store.Config{Bucket: "boltDBTest"}, ) assert.NoError(t, err) assert.NotNil(t, kv) if _, ok := kv.(*BoltDB); !ok { t.Fatal("Error registering and initializing boltDB") } _ = os.Remove("/tmp/not_exist_dir/__boltdbtest") } // TestMultiplePersistConnection tests the second connection to a // BoltDB fails when one is already open with PersistConnection flag func TestMultiplePersistConnection(t *testing.T) { kv, err := libkv.NewStore( store.BOLTDB, []string{"/tmp/not_exist_dir/__boltdbtest"}, &store.Config{ Bucket: "boltDBTest", ConnectionTimeout: 1 * time.Second, PersistConnection: true}, ) assert.NoError(t, err) assert.NotNil(t, kv) if _, ok := kv.(*BoltDB); !ok { t.Fatal("Error registering and initializing boltDB") } // Must fail if multiple boltdb requests are made with a valid timeout kv, err = libkv.NewStore( store.BOLTDB, []string{"/tmp/not_exist_dir/__boltdbtest"}, &store.Config{ Bucket: "boltDBTest", ConnectionTimeout: 1 * time.Second, PersistConnection: true}, ) assert.Error(t, err) _ = os.Remove("/tmp/not_exist_dir/__boltdbtest") } // TestConcurrentConnection tests simultaenous get/put using // two handles. func TestConcurrentConnection(t *testing.T) { var err error kv1, err1 := libkv.NewStore( store.BOLTDB, []string{"/tmp/__boltdbtest"}, &store.Config{ Bucket: "boltDBTest", ConnectionTimeout: 1 * time.Second}, ) assert.NoError(t, err1) assert.NotNil(t, kv1) kv2, err2 := libkv.NewStore( store.BOLTDB, []string{"/tmp/__boltdbtest"}, &store.Config{Bucket: "boltDBTest", ConnectionTimeout: 1 * time.Second}, ) assert.NoError(t, err2) assert.NotNil(t, kv2) key1 := "TestKV1" value1 := []byte("TestVal1") err = kv1.Put(key1, value1, nil) assert.NoError(t, err) key2 := "TestKV2" value2 := []byte("TestVal2") err = kv2.Put(key2, value2, nil) assert.NoError(t, err) pair1, err1 := kv1.Get(key1) assert.NoError(t, err) if assert.NotNil(t, pair1) { assert.NotNil(t, pair1.Value) } assert.Equal(t, pair1.Value, value1) pair2, err2 := kv2.Get(key2) assert.NoError(t, err) if assert.NotNil(t, pair2) { assert.NotNil(t, pair2.Value) } assert.Equal(t, pair2.Value, value2) // AtomicPut using kv1 and kv2 should succeed _, _, err = kv1.AtomicPut(key1, []byte("TestnewVal1"), pair1, nil) assert.NoError(t, err) _, _, err = kv2.AtomicPut(key2, []byte("TestnewVal2"), pair2, nil) assert.NoError(t, err) testutils.RunTestCommon(t, kv1) testutils.RunTestCommon(t, kv2) kv1.Close() kv2.Close() _ = os.Remove("/tmp/__boltdbtest") } func TestBoldDBStore(t *testing.T) { kv := makeBoltDBClient(t) testutils.RunTestCommon(t, kv) testutils.RunTestAtomic(t, kv) _ = os.Remove("/tmp/not_exist_dir/__boltdbtest") } libkv-0.1.0/store/consul/000077500000000000000000000000001261675717100152735ustar00rootroot00000000000000libkv-0.1.0/store/consul/consul.go000066400000000000000000000272761261675717100171430ustar00rootroot00000000000000package consul import ( "crypto/tls" "errors" "net/http" "strings" "sync" "time" "github.com/docker/libkv" "github.com/docker/libkv/store" api "github.com/hashicorp/consul/api" ) const ( // DefaultWatchWaitTime is how long we block for at a // time to check if the watched key has changed. This // affects the minimum time it takes to cancel a watch. DefaultWatchWaitTime = 15 * time.Second // RenewSessionRetryMax is the number of time we should try // to renew the session before giving up and throwing an error RenewSessionRetryMax = 5 ) var ( // ErrMultipleEndpointsUnsupported is thrown when there are // multiple endpoints specified for Consul ErrMultipleEndpointsUnsupported = errors.New("consul does not support multiple endpoints") // ErrSessionRenew is thrown when the session can't be // renewed because the Consul version does not support sessions ErrSessionRenew = errors.New("cannot set or renew session for ttl, unable to operate on sessions") ) // Consul is the receiver type for the // Store interface type Consul struct { sync.Mutex config *api.Config client *api.Client } type consulLock struct { lock *api.Lock renewCh chan struct{} } // Register registers consul to libkv func Register() { libkv.AddStore(store.CONSUL, New) } // New creates a new Consul client given a list // of endpoints and optional tls config func New(endpoints []string, options *store.Config) (store.Store, error) { if len(endpoints) > 1 { return nil, ErrMultipleEndpointsUnsupported } s := &Consul{} // Create Consul client config := api.DefaultConfig() s.config = config config.HttpClient = http.DefaultClient config.Address = endpoints[0] config.Scheme = "http" // Set options if options != nil { if options.TLS != nil { s.setTLS(options.TLS) } if options.ConnectionTimeout != 0 { s.setTimeout(options.ConnectionTimeout) } } // Creates a new client client, err := api.NewClient(config) if err != nil { return nil, err } s.client = client return s, nil } // SetTLS sets Consul TLS options func (s *Consul) setTLS(tls *tls.Config) { s.config.HttpClient.Transport = &http.Transport{ TLSClientConfig: tls, } s.config.Scheme = "https" } // SetTimeout sets the timeout for connecting to Consul func (s *Consul) setTimeout(time time.Duration) { s.config.WaitTime = time } // Normalize the key for usage in Consul func (s *Consul) normalize(key string) string { key = store.Normalize(key) return strings.TrimPrefix(key, "/") } func (s *Consul) renewSession(pair *api.KVPair, ttl time.Duration) error { // Check if there is any previous session with an active TTL session, err := s.getActiveSession(pair.Key) if err != nil { return err } if session == "" { entry := &api.SessionEntry{ Behavior: api.SessionBehaviorDelete, // Delete the key when the session expires TTL: (ttl / 2).String(), // Consul multiplies the TTL by 2x LockDelay: 1 * time.Millisecond, // Virtually disable lock delay } // Create the key session session, _, err = s.client.Session().Create(entry, nil) if err != nil { return err } lockOpts := &api.LockOptions{ Key: pair.Key, Session: session, } // Lock and ignore if lock is held // It's just a placeholder for the // ephemeral behavior lock, _ := s.client.LockOpts(lockOpts) if lock != nil { lock.Lock(nil) } } _, _, err = s.client.Session().Renew(session, nil) return err } // getActiveSession checks if the key already has // a session attached func (s *Consul) getActiveSession(key string) (string, error) { pair, _, err := s.client.KV().Get(key, nil) if err != nil { return "", err } if pair != nil && pair.Session != "" { return pair.Session, nil } return "", nil } // Get the value at "key", returns the last modified index // to use in conjunction to CAS calls func (s *Consul) Get(key string) (*store.KVPair, error) { options := &api.QueryOptions{ AllowStale: false, RequireConsistent: true, } pair, meta, err := s.client.KV().Get(s.normalize(key), options) if err != nil { return nil, err } // If pair is nil then the key does not exist if pair == nil { return nil, store.ErrKeyNotFound } return &store.KVPair{Key: pair.Key, Value: pair.Value, LastIndex: meta.LastIndex}, nil } // Put a value at "key" func (s *Consul) Put(key string, value []byte, opts *store.WriteOptions) error { key = s.normalize(key) p := &api.KVPair{ Key: key, Value: value, } if opts != nil && opts.TTL > 0 { // Create or renew a session holding a TTL. Operations on sessions // are not deterministic: creating or renewing a session can fail for retry := 1; retry <= RenewSessionRetryMax; retry++ { err := s.renewSession(p, opts.TTL) if err == nil { break } if retry == RenewSessionRetryMax { return ErrSessionRenew } } } _, err := s.client.KV().Put(p, nil) return err } // Delete a value at "key" func (s *Consul) Delete(key string) error { if _, err := s.Get(key); err != nil { return err } _, err := s.client.KV().Delete(s.normalize(key), nil) return err } // Exists checks that the key exists inside the store func (s *Consul) Exists(key string) (bool, error) { _, err := s.Get(key) if err != nil { if err == store.ErrKeyNotFound { return false, nil } return false, err } return true, nil } // List child nodes of a given directory func (s *Consul) List(directory string) ([]*store.KVPair, error) { pairs, _, err := s.client.KV().List(s.normalize(directory), nil) if err != nil { return nil, err } if len(pairs) == 0 { return nil, store.ErrKeyNotFound } kv := []*store.KVPair{} for _, pair := range pairs { if pair.Key == directory { continue } kv = append(kv, &store.KVPair{ Key: pair.Key, Value: pair.Value, LastIndex: pair.ModifyIndex, }) } return kv, nil } // DeleteTree deletes a range of keys under a given directory func (s *Consul) DeleteTree(directory string) error { if _, err := s.List(directory); err != nil { return err } _, err := s.client.KV().DeleteTree(s.normalize(directory), nil) return err } // Watch for changes on a "key" // It returns a channel that will receive changes or pass // on errors. Upon creation, the current value will first // be sent to the channel. Providing a non-nil stopCh can // be used to stop watching. func (s *Consul) Watch(key string, stopCh <-chan struct{}) (<-chan *store.KVPair, error) { kv := s.client.KV() watchCh := make(chan *store.KVPair) go func() { defer close(watchCh) // Use a wait time in order to check if we should quit // from time to time. opts := &api.QueryOptions{WaitTime: DefaultWatchWaitTime} for { // Check if we should quit select { case <-stopCh: return default: } // Get the key pair, meta, err := kv.Get(key, opts) if err != nil { return } // If LastIndex didn't change then it means `Get` returned // because of the WaitTime and the key didn't changed. if opts.WaitIndex == meta.LastIndex { continue } opts.WaitIndex = meta.LastIndex // Return the value to the channel // FIXME: What happens when a key is deleted? if pair != nil { watchCh <- &store.KVPair{ Key: pair.Key, Value: pair.Value, LastIndex: pair.ModifyIndex, } } } }() return watchCh, nil } // WatchTree watches for changes on a "directory" // It returns a channel that will receive changes or pass // on errors. Upon creating a watch, the current childs values // will be sent to the channel .Providing a non-nil stopCh can // be used to stop watching. func (s *Consul) WatchTree(directory string, stopCh <-chan struct{}) (<-chan []*store.KVPair, error) { kv := s.client.KV() watchCh := make(chan []*store.KVPair) go func() { defer close(watchCh) // Use a wait time in order to check if we should quit // from time to time. opts := &api.QueryOptions{WaitTime: DefaultWatchWaitTime} for { // Check if we should quit select { case <-stopCh: return default: } // Get all the childrens pairs, meta, err := kv.List(directory, opts) if err != nil { return } // If LastIndex didn't change then it means `Get` returned // because of the WaitTime and the child keys didn't change. if opts.WaitIndex == meta.LastIndex { continue } opts.WaitIndex = meta.LastIndex // Return children KV pairs to the channel kvpairs := []*store.KVPair{} for _, pair := range pairs { if pair.Key == directory { continue } kvpairs = append(kvpairs, &store.KVPair{ Key: pair.Key, Value: pair.Value, LastIndex: pair.ModifyIndex, }) } watchCh <- kvpairs } }() return watchCh, nil } // NewLock returns a handle to a lock struct which can // be used to provide mutual exclusion on a key func (s *Consul) NewLock(key string, options *store.LockOptions) (store.Locker, error) { lockOpts := &api.LockOptions{ Key: s.normalize(key), } lock := &consulLock{} if options != nil { // Set optional TTL on Lock if options.TTL != 0 { entry := &api.SessionEntry{ Behavior: api.SessionBehaviorRelease, // Release the lock when the session expires TTL: (options.TTL / 2).String(), // Consul multiplies the TTL by 2x LockDelay: 1 * time.Millisecond, // Virtually disable lock delay } // Create the key session session, _, err := s.client.Session().Create(entry, nil) if err != nil { return nil, err } // Place the session on lock lockOpts.Session = session // Renew the session ttl lock periodically go s.client.Session().RenewPeriodic(entry.TTL, session, nil, options.RenewLock) lock.renewCh = options.RenewLock } // Set optional value on Lock if options.Value != nil { lockOpts.Value = options.Value } } l, err := s.client.LockOpts(lockOpts) if err != nil { return nil, err } lock.lock = l return lock, nil } // Lock attempts to acquire the lock and blocks while // doing so. It returns a channel that is closed if our // lock is lost or if an error occurs func (l *consulLock) Lock(stopChan chan struct{}) (<-chan struct{}, error) { return l.lock.Lock(stopChan) } // Unlock the "key". Calling unlock while // not holding the lock will throw an error func (l *consulLock) Unlock() error { if l.renewCh != nil { close(l.renewCh) } return l.lock.Unlock() } // AtomicPut put a value at "key" if the key has not been // modified in the meantime, throws an error if this is the case func (s *Consul) AtomicPut(key string, value []byte, previous *store.KVPair, options *store.WriteOptions) (bool, *store.KVPair, error) { p := &api.KVPair{Key: s.normalize(key), Value: value} if previous == nil { // Consul interprets ModifyIndex = 0 as new key. p.ModifyIndex = 0 } else { p.ModifyIndex = previous.LastIndex } ok, _, err := s.client.KV().CAS(p, nil) if err != nil { return false, nil, err } if !ok { if previous == nil { return false, nil, store.ErrKeyExists } return false, nil, store.ErrKeyModified } pair, err := s.Get(key) if err != nil { return false, nil, err } return true, pair, nil } // AtomicDelete deletes a value at "key" if the key has not // been modified in the meantime, throws an error if this is the case func (s *Consul) AtomicDelete(key string, previous *store.KVPair) (bool, error) { if previous == nil { return false, store.ErrPreviousNotSpecified } p := &api.KVPair{Key: s.normalize(key), ModifyIndex: previous.LastIndex} // Extra Get operation to check on the key _, err := s.Get(key) if err != nil && err == store.ErrKeyNotFound { return false, err } if work, _, err := s.client.KV().DeleteCAS(p, nil); err != nil { return false, err } else if !work { return false, store.ErrKeyModified } return true, nil } // Close closes the client connection func (s *Consul) Close() { return } libkv-0.1.0/store/consul/consul_test.go000066400000000000000000000032361261675717100201700ustar00rootroot00000000000000package consul import ( "testing" "time" "github.com/docker/libkv" "github.com/docker/libkv/store" "github.com/docker/libkv/testutils" "github.com/stretchr/testify/assert" ) var ( client = "localhost:8500" ) func makeConsulClient(t *testing.T) store.Store { kv, err := New( []string{client}, &store.Config{ ConnectionTimeout: 3 * time.Second, }, ) if err != nil { t.Fatalf("cannot create store: %v", err) } return kv } func TestRegister(t *testing.T) { Register() kv, err := libkv.NewStore(store.CONSUL, []string{client}, nil) assert.NoError(t, err) assert.NotNil(t, kv) if _, ok := kv.(*Consul); !ok { t.Fatal("Error registering and initializing consul") } } func TestConsulStore(t *testing.T) { kv := makeConsulClient(t) lockKV := makeConsulClient(t) ttlKV := makeConsulClient(t) testutils.RunTestCommon(t, kv) testutils.RunTestAtomic(t, kv) testutils.RunTestWatch(t, kv) testutils.RunTestLock(t, kv) testutils.RunTestLockTTL(t, kv, lockKV) testutils.RunTestTTL(t, kv, ttlKV) testutils.RunCleanup(t, kv) } func TestGetActiveSession(t *testing.T) { kv := makeConsulClient(t) consul := kv.(*Consul) key := "foo" value := []byte("bar") // Put the first key with the Ephemeral flag err := kv.Put(key, value, &store.WriteOptions{TTL: 2 * time.Second}) assert.NoError(t, err) // Session should not be empty session, err := consul.getActiveSession(key) assert.NoError(t, err) assert.NotEqual(t, session, "") // Delete the key err = kv.Delete(key) assert.NoError(t, err) // Check the session again, it should return nothing session, err = consul.getActiveSession(key) assert.NoError(t, err) assert.Equal(t, session, "") } libkv-0.1.0/store/etcd/000077500000000000000000000000001261675717100147075ustar00rootroot00000000000000libkv-0.1.0/store/etcd/etcd.go000066400000000000000000000321411261675717100161560ustar00rootroot00000000000000package etcd import ( "crypto/tls" "errors" "log" "net" "net/http" "strings" "time" "golang.org/x/net/context" etcd "github.com/coreos/etcd/client" "github.com/docker/libkv" "github.com/docker/libkv/store" ) var ( // ErrAbortTryLock is thrown when a user stops trying to seek the lock // by sending a signal to the stop chan, this is used to verify if the // operation succeeded ErrAbortTryLock = errors.New("lock operation aborted") ) // Etcd is the receiver type for the // Store interface type Etcd struct { client etcd.KeysAPI } type etcdLock struct { client etcd.KeysAPI stopLock chan struct{} stopRenew chan struct{} key string value string last *etcd.Response ttl time.Duration } const ( periodicSync = 5 * time.Minute defaultLockTTL = 20 * time.Second defaultUpdateTime = 5 * time.Second ) // Register registers etcd to libkv func Register() { libkv.AddStore(store.ETCD, New) } // New creates a new Etcd client given a list // of endpoints and an optional tls config func New(addrs []string, options *store.Config) (store.Store, error) { s := &Etcd{} var ( entries []string err error ) entries = store.CreateEndpoints(addrs, "http") cfg := &etcd.Config{ Endpoints: entries, Transport: etcd.DefaultTransport, HeaderTimeoutPerRequest: 3 * time.Second, } // Set options if options != nil { if options.TLS != nil { setTLS(cfg, options.TLS, addrs) } if options.ConnectionTimeout != 0 { setTimeout(cfg, options.ConnectionTimeout) } } c, err := etcd.New(*cfg) if err != nil { log.Fatal(err) } s.client = etcd.NewKeysAPI(c) // Periodic Cluster Sync go func() { for { if err := c.AutoSync(context.Background(), periodicSync); err != nil { return } } }() return s, nil } // SetTLS sets the tls configuration given a tls.Config scheme func setTLS(cfg *etcd.Config, tls *tls.Config, addrs []string) { entries := store.CreateEndpoints(addrs, "https") cfg.Endpoints = entries // Set transport t := http.Transport{ Dial: (&net.Dialer{ Timeout: 30 * time.Second, KeepAlive: 30 * time.Second, }).Dial, TLSHandshakeTimeout: 10 * time.Second, TLSClientConfig: tls, } cfg.Transport = &t } // setTimeout sets the timeout used for connecting to the store func setTimeout(cfg *etcd.Config, time time.Duration) { cfg.HeaderTimeoutPerRequest = time } // Normalize the key for usage in Etcd func (s *Etcd) normalize(key string) string { key = store.Normalize(key) return strings.TrimPrefix(key, "/") } // keyNotFound checks on the error returned by the KeysAPI // to verify if the key exists in the store or not func keyNotFound(err error) bool { if err != nil { if etcdError, ok := err.(etcd.Error); ok { if etcdError.Code == etcd.ErrorCodeKeyNotFound || etcdError.Code == etcd.ErrorCodeNotFile || etcdError.Code == etcd.ErrorCodeNotDir { return true } } } return false } // Get the value at "key", returns the last modified // index to use in conjunction to Atomic calls func (s *Etcd) Get(key string) (pair *store.KVPair, err error) { getOpts := &etcd.GetOptions{ Quorum: true, } result, err := s.client.Get(context.Background(), s.normalize(key), getOpts) if err != nil { if keyNotFound(err) { return nil, store.ErrKeyNotFound } return nil, err } pair = &store.KVPair{ Key: key, Value: []byte(result.Node.Value), LastIndex: result.Node.ModifiedIndex, } return pair, nil } // Put a value at "key" func (s *Etcd) Put(key string, value []byte, opts *store.WriteOptions) error { setOpts := &etcd.SetOptions{} // Set options if opts != nil { setOpts.Dir = opts.IsDir setOpts.TTL = opts.TTL } _, err := s.client.Set(context.Background(), s.normalize(key), string(value), setOpts) return err } // Delete a value at "key" func (s *Etcd) Delete(key string) error { opts := &etcd.DeleteOptions{ Recursive: false, } _, err := s.client.Delete(context.Background(), s.normalize(key), opts) if keyNotFound(err) { return store.ErrKeyNotFound } return err } // Exists checks if the key exists inside the store func (s *Etcd) Exists(key string) (bool, error) { _, err := s.Get(key) if err != nil { if err == store.ErrKeyNotFound { return false, nil } return false, err } return true, nil } // Watch for changes on a "key" // It returns a channel that will receive changes or pass // on errors. Upon creation, the current value will first // be sent to the channel. Providing a non-nil stopCh can // be used to stop watching. func (s *Etcd) Watch(key string, stopCh <-chan struct{}) (<-chan *store.KVPair, error) { opts := &etcd.WatcherOptions{Recursive: false} watcher := s.client.Watcher(s.normalize(key), opts) // watchCh is sending back events to the caller watchCh := make(chan *store.KVPair) go func() { defer close(watchCh) // Get the current value pair, err := s.Get(key) if err != nil { return } // Push the current value through the channel. watchCh <- pair for { // Check if the watch was stopped by the caller select { case <-stopCh: return default: } result, err := watcher.Next(context.Background()) if err != nil { return } watchCh <- &store.KVPair{ Key: key, Value: []byte(result.Node.Value), LastIndex: result.Node.ModifiedIndex, } } }() return watchCh, nil } // WatchTree watches for changes on a "directory" // It returns a channel that will receive changes or pass // on errors. Upon creating a watch, the current childs values // will be sent to the channel. Providing a non-nil stopCh can // be used to stop watching. func (s *Etcd) WatchTree(directory string, stopCh <-chan struct{}) (<-chan []*store.KVPair, error) { watchOpts := &etcd.WatcherOptions{Recursive: true} watcher := s.client.Watcher(s.normalize(directory), watchOpts) // watchCh is sending back events to the caller watchCh := make(chan []*store.KVPair) go func() { defer close(watchCh) // Get child values list, err := s.List(directory) if err != nil { return } // Push the current value through the channel. watchCh <- list for { // Check if the watch was stopped by the caller select { case <-stopCh: return default: } _, err := watcher.Next(context.Background()) if err != nil { return } list, err = s.List(directory) if err != nil { return } watchCh <- list } }() return watchCh, nil } // AtomicPut puts a value at "key" if the key has not been // modified in the meantime, throws an error if this is the case func (s *Etcd) AtomicPut(key string, value []byte, previous *store.KVPair, opts *store.WriteOptions) (bool, *store.KVPair, error) { var ( meta *etcd.Response err error ) setOpts := &etcd.SetOptions{} if previous != nil { setOpts.PrevExist = etcd.PrevExist setOpts.PrevIndex = previous.LastIndex if previous.Value != nil { setOpts.PrevValue = string(previous.Value) } } else { setOpts.PrevExist = etcd.PrevNoExist } if opts != nil { if opts.TTL > 0 { setOpts.TTL = opts.TTL } } meta, err = s.client.Set(context.Background(), s.normalize(key), string(value), setOpts) if err != nil { if etcdError, ok := err.(etcd.Error); ok { // Compare failed if etcdError.Code == etcd.ErrorCodeTestFailed { return false, nil, store.ErrKeyModified } // Node exists error (when PrevNoExist) if etcdError.Code == etcd.ErrorCodeNodeExist { return false, nil, store.ErrKeyExists } } return false, nil, err } updated := &store.KVPair{ Key: key, Value: value, LastIndex: meta.Node.ModifiedIndex, } return true, updated, nil } // AtomicDelete deletes a value at "key" if the key // has not been modified in the meantime, throws an // error if this is the case func (s *Etcd) AtomicDelete(key string, previous *store.KVPair) (bool, error) { if previous == nil { return false, store.ErrPreviousNotSpecified } delOpts := &etcd.DeleteOptions{} if previous != nil { delOpts.PrevIndex = previous.LastIndex if previous.Value != nil { delOpts.PrevValue = string(previous.Value) } } _, err := s.client.Delete(context.Background(), s.normalize(key), delOpts) if err != nil { if etcdError, ok := err.(etcd.Error); ok { // Key Not Found if etcdError.Code == etcd.ErrorCodeKeyNotFound { return false, store.ErrKeyNotFound } // Compare failed if etcdError.Code == etcd.ErrorCodeTestFailed { return false, store.ErrKeyModified } } return false, err } return true, nil } // List child nodes of a given directory func (s *Etcd) List(directory string) ([]*store.KVPair, error) { getOpts := &etcd.GetOptions{ Quorum: true, Recursive: true, Sort: true, } resp, err := s.client.Get(context.Background(), s.normalize(directory), getOpts) if err != nil { if keyNotFound(err) { return nil, store.ErrKeyNotFound } return nil, err } kv := []*store.KVPair{} for _, n := range resp.Node.Nodes { kv = append(kv, &store.KVPair{ Key: n.Key, Value: []byte(n.Value), LastIndex: n.ModifiedIndex, }) } return kv, nil } // DeleteTree deletes a range of keys under a given directory func (s *Etcd) DeleteTree(directory string) error { delOpts := &etcd.DeleteOptions{ Recursive: true, } _, err := s.client.Delete(context.Background(), s.normalize(directory), delOpts) if keyNotFound(err) { return store.ErrKeyNotFound } return err } // NewLock returns a handle to a lock struct which can // be used to provide mutual exclusion on a key func (s *Etcd) NewLock(key string, options *store.LockOptions) (lock store.Locker, err error) { var value string ttl := defaultLockTTL renewCh := make(chan struct{}) // Apply options on Lock if options != nil { if options.Value != nil { value = string(options.Value) } if options.TTL != 0 { ttl = options.TTL } if options.RenewLock != nil { renewCh = options.RenewLock } } // Create lock object lock = &etcdLock{ client: s.client, stopRenew: renewCh, key: s.normalize(key), value: value, ttl: ttl, } return lock, nil } // Lock attempts to acquire the lock and blocks while // doing so. It returns a channel that is closed if our // lock is lost or if an error occurs func (l *etcdLock) Lock(stopChan chan struct{}) (<-chan struct{}, error) { // Lock holder channel lockHeld := make(chan struct{}) stopLocking := l.stopRenew setOpts := &etcd.SetOptions{ TTL: l.ttl, } for { setOpts.PrevExist = etcd.PrevNoExist resp, err := l.client.Set(context.Background(), l.key, l.value, setOpts) if err != nil { if etcdError, ok := err.(etcd.Error); ok { if etcdError.Code != etcd.ErrorCodeNodeExist { return nil, err } setOpts.PrevIndex = ^uint64(0) } } else { setOpts.PrevIndex = resp.Node.ModifiedIndex } setOpts.PrevExist = etcd.PrevExist l.last, err = l.client.Set(context.Background(), l.key, l.value, setOpts) if err == nil { // Leader section l.stopLock = stopLocking go l.holdLock(l.key, lockHeld, stopLocking) break } else { // If this is a legitimate error, return if etcdError, ok := err.(etcd.Error); ok { if etcdError.Code != etcd.ErrorCodeTestFailed { return nil, err } } // Seeker section errorCh := make(chan error) chWStop := make(chan bool) free := make(chan bool) go l.waitLock(l.key, errorCh, chWStop, free) // Wait for the key to be available or for // a signal to stop trying to lock the key select { case _ = <-free: break case err := <-errorCh: return nil, err case _ = <-stopChan: return nil, ErrAbortTryLock } // Delete or Expire event occured // Retry } } return lockHeld, nil } // Hold the lock as long as we can // Updates the key ttl periodically until we receive // an explicit stop signal from the Unlock method func (l *etcdLock) holdLock(key string, lockHeld chan struct{}, stopLocking <-chan struct{}) { defer close(lockHeld) update := time.NewTicker(l.ttl / 3) defer update.Stop() var err error setOpts := &etcd.SetOptions{TTL: l.ttl} for { select { case <-update.C: setOpts.PrevIndex = l.last.Node.ModifiedIndex l.last, err = l.client.Set(context.Background(), key, l.value, setOpts) if err != nil { return } case <-stopLocking: return } } } // WaitLock simply waits for the key to be available for creation func (l *etcdLock) waitLock(key string, errorCh chan error, stopWatchCh chan bool, free chan<- bool) { opts := &etcd.WatcherOptions{Recursive: false} watcher := l.client.Watcher(key, opts) for { event, err := watcher.Next(context.Background()) if err != nil { errorCh <- err return } if event.Action == "delete" || event.Action == "expire" { free <- true return } } } // Unlock the "key". Calling unlock while // not holding the lock will throw an error func (l *etcdLock) Unlock() error { if l.stopLock != nil { l.stopLock <- struct{}{} } if l.last != nil { delOpts := &etcd.DeleteOptions{ PrevIndex: l.last.Node.ModifiedIndex, } _, err := l.client.Delete(context.Background(), l.key, delOpts) if err != nil { return err } } return nil } // Close closes the client connection func (s *Etcd) Close() { return } libkv-0.1.0/store/etcd/etcd_test.go000066400000000000000000000020221261675717100172100ustar00rootroot00000000000000package etcd import ( "testing" "time" "github.com/docker/libkv" "github.com/docker/libkv/store" "github.com/docker/libkv/testutils" "github.com/stretchr/testify/assert" ) var ( client = "localhost:4001" ) func makeEtcdClient(t *testing.T) store.Store { kv, err := New( []string{client}, &store.Config{ ConnectionTimeout: 3 * time.Second, }, ) if err != nil { t.Fatalf("cannot create store: %v", err) } return kv } func TestRegister(t *testing.T) { Register() kv, err := libkv.NewStore(store.ETCD, []string{client}, nil) assert.NoError(t, err) assert.NotNil(t, kv) if _, ok := kv.(*Etcd); !ok { t.Fatal("Error registering and initializing etcd") } } func TestEtcdStore(t *testing.T) { kv := makeEtcdClient(t) lockKV := makeEtcdClient(t) ttlKV := makeEtcdClient(t) testutils.RunTestCommon(t, kv) testutils.RunTestAtomic(t, kv) testutils.RunTestWatch(t, kv) testutils.RunTestLock(t, kv) testutils.RunTestLockTTL(t, kv, lockKV) testutils.RunTestTTL(t, kv, ttlKV) testutils.RunCleanup(t, kv) } libkv-0.1.0/store/helpers.go000066400000000000000000000017051261675717100157640ustar00rootroot00000000000000package store import ( "strings" ) // CreateEndpoints creates a list of endpoints given the right scheme func CreateEndpoints(addrs []string, scheme string) (entries []string) { for _, addr := range addrs { entries = append(entries, scheme+"://"+addr) } return entries } // Normalize the key for each store to the form: // // /path/to/key // func Normalize(key string) string { return "/" + join(SplitKey(key)) } // GetDirectory gets the full directory part of // the key to the form: // // /path/to/ // func GetDirectory(key string) string { parts := SplitKey(key) parts = parts[:len(parts)-1] return "/" + join(parts) } // SplitKey splits the key to extract path informations func SplitKey(key string) (path []string) { if strings.Contains(key, "/") { path = strings.Split(key, "/") } else { path = []string{key} } return path } // join the path parts with '/' func join(parts []string) string { return strings.Join(parts, "/") } libkv-0.1.0/store/mock/000077500000000000000000000000001261675717100147215ustar00rootroot00000000000000libkv-0.1.0/store/mock/mock.go000066400000000000000000000053171261675717100162070ustar00rootroot00000000000000package mock import ( "github.com/docker/libkv/store" "github.com/stretchr/testify/mock" ) // Mock store. Mocks all Store functions using testify.Mock type Mock struct { mock.Mock // Endpoints passed to InitializeMock Endpoints []string // Options passed to InitializeMock Options *store.Config } // New creates a Mock store func New(endpoints []string, options *store.Config) (store.Store, error) { s := &Mock{} s.Endpoints = endpoints s.Options = options return s, nil } // Put mock func (s *Mock) Put(key string, value []byte, opts *store.WriteOptions) error { args := s.Mock.Called(key, value, opts) return args.Error(0) } // Get mock func (s *Mock) Get(key string) (*store.KVPair, error) { args := s.Mock.Called(key) return args.Get(0).(*store.KVPair), args.Error(1) } // Delete mock func (s *Mock) Delete(key string) error { args := s.Mock.Called(key) return args.Error(0) } // Exists mock func (s *Mock) Exists(key string) (bool, error) { args := s.Mock.Called(key) return args.Bool(0), args.Error(1) } // Watch mock func (s *Mock) Watch(key string, stopCh <-chan struct{}) (<-chan *store.KVPair, error) { args := s.Mock.Called(key, stopCh) return args.Get(0).(<-chan *store.KVPair), args.Error(1) } // WatchTree mock func (s *Mock) WatchTree(prefix string, stopCh <-chan struct{}) (<-chan []*store.KVPair, error) { args := s.Mock.Called(prefix, stopCh) return args.Get(0).(chan []*store.KVPair), args.Error(1) } // NewLock mock func (s *Mock) NewLock(key string, options *store.LockOptions) (store.Locker, error) { args := s.Mock.Called(key, options) return args.Get(0).(store.Locker), args.Error(1) } // List mock func (s *Mock) List(prefix string) ([]*store.KVPair, error) { args := s.Mock.Called(prefix) return args.Get(0).([]*store.KVPair), args.Error(1) } // DeleteTree mock func (s *Mock) DeleteTree(prefix string) error { args := s.Mock.Called(prefix) return args.Error(0) } // AtomicPut mock func (s *Mock) AtomicPut(key string, value []byte, previous *store.KVPair, opts *store.WriteOptions) (bool, *store.KVPair, error) { args := s.Mock.Called(key, value, previous, opts) return args.Bool(0), args.Get(1).(*store.KVPair), args.Error(2) } // AtomicDelete mock func (s *Mock) AtomicDelete(key string, previous *store.KVPair) (bool, error) { args := s.Mock.Called(key, previous) return args.Bool(0), args.Error(1) } // Lock mock implementation of Locker type Lock struct { mock.Mock } // Lock mock func (l *Lock) Lock(stopCh chan struct{}) (<-chan struct{}, error) { args := l.Mock.Called(stopCh) return args.Get(0).(<-chan struct{}), args.Error(1) } // Unlock mock func (l *Lock) Unlock() error { args := l.Mock.Called() return args.Error(0) } // Close mock func (s *Mock) Close() { return } libkv-0.1.0/store/store.go000066400000000000000000000104531261675717100154560ustar00rootroot00000000000000package store import ( "crypto/tls" "errors" "time" ) // Backend represents a KV Store Backend type Backend string const ( // CONSUL backend CONSUL Backend = "consul" // ETCD backend ETCD Backend = "etcd" // ZK backend ZK Backend = "zk" // BOLTDB backend BOLTDB Backend = "boltdb" ) var ( // ErrBackendNotSupported is thrown when the backend k/v store is not supported by libkv ErrBackendNotSupported = errors.New("Backend storage not supported yet, please choose one of") // ErrCallNotSupported is thrown when a method is not implemented/supported by the current backend ErrCallNotSupported = errors.New("The current call is not supported with this backend") // ErrNotReachable is thrown when the API cannot be reached for issuing common store operations ErrNotReachable = errors.New("Api not reachable") // ErrCannotLock is thrown when there is an error acquiring a lock on a key ErrCannotLock = errors.New("Error acquiring the lock") // ErrKeyModified is thrown during an atomic operation if the index does not match the one in the store ErrKeyModified = errors.New("Unable to complete atomic operation, key modified") // ErrKeyNotFound is thrown when the key is not found in the store during a Get operation ErrKeyNotFound = errors.New("Key not found in store") // ErrPreviousNotSpecified is thrown when the previous value is not specified for an atomic operation ErrPreviousNotSpecified = errors.New("Previous K/V pair should be provided for the Atomic operation") // ErrKeyExists is thrown when the previous value exists in the case of an AtomicPut ErrKeyExists = errors.New("Previous K/V pair exists, cannnot complete Atomic operation") ) // Config contains the options for a storage client type Config struct { ClientTLS *ClientTLSConfig TLS *tls.Config ConnectionTimeout time.Duration Bucket string PersistConnection bool } // ClientTLSConfig contains data for a Client TLS configuration in the form // the etcd client wants it. Eventually we'll adapt it for ZK and Consul. type ClientTLSConfig struct { CertFile string KeyFile string CACertFile string } // Store represents the backend K/V storage // Each store should support every call listed // here. Or it couldn't be implemented as a K/V // backend for libkv type Store interface { // Put a value at the specified key Put(key string, value []byte, options *WriteOptions) error // Get a value given its key Get(key string) (*KVPair, error) // Delete the value at the specified key Delete(key string) error // Verify if a Key exists in the store Exists(key string) (bool, error) // Watch for changes on a key Watch(key string, stopCh <-chan struct{}) (<-chan *KVPair, error) // WatchTree watches for changes on child nodes under // a given directory WatchTree(directory string, stopCh <-chan struct{}) (<-chan []*KVPair, error) // NewLock creates a lock for a given key. // The returned Locker is not held and must be acquired // with `.Lock`. The Value is optional. NewLock(key string, options *LockOptions) (Locker, error) // List the content of a given prefix List(directory string) ([]*KVPair, error) // DeleteTree deletes a range of keys under a given directory DeleteTree(directory string) error // Atomic CAS operation on a single value. // Pass previous = nil to create a new key. AtomicPut(key string, value []byte, previous *KVPair, options *WriteOptions) (bool, *KVPair, error) // Atomic delete of a single value AtomicDelete(key string, previous *KVPair) (bool, error) // Close the store connection Close() } // KVPair represents {Key, Value, Lastindex} tuple type KVPair struct { Key string Value []byte LastIndex uint64 } // WriteOptions contains optional request parameters type WriteOptions struct { IsDir bool TTL time.Duration } // LockOptions contains optional request parameters type LockOptions struct { Value []byte // Optional, value to associate with the lock TTL time.Duration // Optional, expiration ttl associated with the lock RenewLock chan struct{} // Optional, chan used to control and stop the session ttl renewal for the lock } // Locker provides locking mechanism on top of the store. // Similar to `sync.Lock` except it may return errors. type Locker interface { Lock(stopChan chan struct{}) (<-chan struct{}, error) Unlock() error } libkv-0.1.0/store/zookeeper/000077500000000000000000000000001261675717100157735ustar00rootroot00000000000000libkv-0.1.0/store/zookeeper/zookeeper.go000066400000000000000000000242161261675717100203320ustar00rootroot00000000000000package zookeeper import ( "strings" "time" "github.com/docker/libkv" "github.com/docker/libkv/store" zk "github.com/samuel/go-zookeeper/zk" ) const ( // SOH control character SOH = "\x01" defaultTimeout = 10 * time.Second ) // Zookeeper is the receiver type for // the Store interface type Zookeeper struct { timeout time.Duration client *zk.Conn } type zookeeperLock struct { client *zk.Conn lock *zk.Lock key string value []byte } // Register registers zookeeper to libkv func Register() { libkv.AddStore(store.ZK, New) } // New creates a new Zookeeper client given a // list of endpoints and an optional tls config func New(endpoints []string, options *store.Config) (store.Store, error) { s := &Zookeeper{} s.timeout = defaultTimeout // Set options if options != nil { if options.ConnectionTimeout != 0 { s.setTimeout(options.ConnectionTimeout) } } // Connect to Zookeeper conn, _, err := zk.Connect(endpoints, s.timeout) if err != nil { return nil, err } s.client = conn return s, nil } // setTimeout sets the timeout for connecting to Zookeeper func (s *Zookeeper) setTimeout(time time.Duration) { s.timeout = time } // Get the value at "key", returns the last modified index // to use in conjunction to Atomic calls func (s *Zookeeper) Get(key string) (pair *store.KVPair, err error) { resp, meta, err := s.client.Get(s.normalize(key)) if err != nil { if err == zk.ErrNoNode { return nil, store.ErrKeyNotFound } return nil, err } // FIXME handle very rare cases where Get returns the // SOH control character instead of the actual value if string(resp) == SOH { return s.Get(store.Normalize(key)) } pair = &store.KVPair{ Key: key, Value: resp, LastIndex: uint64(meta.Version), } return pair, nil } // createFullPath creates the entire path for a directory // that does not exist func (s *Zookeeper) createFullPath(path []string, ephemeral bool) error { for i := 1; i <= len(path); i++ { newpath := "/" + strings.Join(path[:i], "/") if i == len(path) && ephemeral { _, err := s.client.Create(newpath, []byte{}, zk.FlagEphemeral, zk.WorldACL(zk.PermAll)) return err } _, err := s.client.Create(newpath, []byte{}, 0, zk.WorldACL(zk.PermAll)) if err != nil { // Skip if node already exists if err != zk.ErrNodeExists { return err } } } return nil } // Put a value at "key" func (s *Zookeeper) Put(key string, value []byte, opts *store.WriteOptions) error { fkey := s.normalize(key) exists, err := s.Exists(key) if err != nil { return err } if !exists { if opts != nil && opts.TTL > 0 { s.createFullPath(store.SplitKey(strings.TrimSuffix(key, "/")), true) } else { s.createFullPath(store.SplitKey(strings.TrimSuffix(key, "/")), false) } } _, err = s.client.Set(fkey, value, -1) return err } // Delete a value at "key" func (s *Zookeeper) Delete(key string) error { err := s.client.Delete(s.normalize(key), -1) if err == zk.ErrNoNode { return store.ErrKeyNotFound } return err } // Exists checks if the key exists inside the store func (s *Zookeeper) Exists(key string) (bool, error) { exists, _, err := s.client.Exists(s.normalize(key)) if err != nil { return false, err } return exists, nil } // Watch for changes on a "key" // It returns a channel that will receive changes or pass // on errors. Upon creation, the current value will first // be sent to the channel. Providing a non-nil stopCh can // be used to stop watching. func (s *Zookeeper) Watch(key string, stopCh <-chan struct{}) (<-chan *store.KVPair, error) { // Get the key first pair, err := s.Get(key) if err != nil { return nil, err } // Catch zk notifications and fire changes into the channel. watchCh := make(chan *store.KVPair) go func() { defer close(watchCh) // Get returns the current value to the channel prior // to listening to any event that may occur on that key watchCh <- pair for { _, _, eventCh, err := s.client.GetW(s.normalize(key)) if err != nil { return } select { case e := <-eventCh: if e.Type == zk.EventNodeDataChanged { if entry, err := s.Get(key); err == nil { watchCh <- entry } } case <-stopCh: // There is no way to stop GetW so just quit return } } }() return watchCh, nil } // WatchTree watches for changes on a "directory" // It returns a channel that will receive changes or pass // on errors. Upon creating a watch, the current childs values // will be sent to the channel .Providing a non-nil stopCh can // be used to stop watching. func (s *Zookeeper) WatchTree(directory string, stopCh <-chan struct{}) (<-chan []*store.KVPair, error) { // List the childrens first entries, err := s.List(directory) if err != nil { return nil, err } // Catch zk notifications and fire changes into the channel. watchCh := make(chan []*store.KVPair) go func() { defer close(watchCh) // List returns the children values to the channel // prior to listening to any events that may occur // on those keys watchCh <- entries for { _, _, eventCh, err := s.client.ChildrenW(s.normalize(directory)) if err != nil { return } select { case e := <-eventCh: if e.Type == zk.EventNodeChildrenChanged { if kv, err := s.List(directory); err == nil { watchCh <- kv } } case <-stopCh: // There is no way to stop GetW so just quit return } } }() return watchCh, nil } // List child nodes of a given directory func (s *Zookeeper) List(directory string) ([]*store.KVPair, error) { keys, stat, err := s.client.Children(s.normalize(directory)) if err != nil { if err == zk.ErrNoNode { return nil, store.ErrKeyNotFound } return nil, err } kv := []*store.KVPair{} // FIXME Costly Get request for each child key.. for _, key := range keys { pair, err := s.Get(strings.TrimSuffix(directory, "/") + s.normalize(key)) if err != nil { // If node is not found: List is out of date, retry if err == zk.ErrNoNode { return s.List(directory) } return nil, err } kv = append(kv, &store.KVPair{ Key: key, Value: []byte(pair.Value), LastIndex: uint64(stat.Version), }) } return kv, nil } // DeleteTree deletes a range of keys under a given directory func (s *Zookeeper) DeleteTree(directory string) error { pairs, err := s.List(directory) if err != nil { return err } var reqs []interface{} for _, pair := range pairs { reqs = append(reqs, &zk.DeleteRequest{ Path: s.normalize(directory + "/" + pair.Key), Version: -1, }) } _, err = s.client.Multi(reqs...) return err } // AtomicPut put a value at "key" if the key has not been // modified in the meantime, throws an error if this is the case func (s *Zookeeper) AtomicPut(key string, value []byte, previous *store.KVPair, _ *store.WriteOptions) (bool, *store.KVPair, error) { var lastIndex uint64 if previous != nil { meta, err := s.client.Set(s.normalize(key), value, int32(previous.LastIndex)) if err != nil { // Compare Failed if err == zk.ErrBadVersion { return false, nil, store.ErrKeyModified } return false, nil, err } lastIndex = uint64(meta.Version) } else { // Interpret previous == nil as create operation. _, err := s.client.Create(s.normalize(key), value, 0, zk.WorldACL(zk.PermAll)) if err != nil { // Directory does not exist if err == zk.ErrNoNode { // Create the directory parts := store.SplitKey(strings.TrimSuffix(key, "/")) parts = parts[:len(parts)-1] if err = s.createFullPath(parts, false); err != nil { // Failed to create the directory. return false, nil, err } // Create the node if _, err := s.client.Create(s.normalize(key), value, 0, zk.WorldACL(zk.PermAll)); err != nil { // Node exist error (when previous nil) if err == zk.ErrNodeExists { return false, nil, store.ErrKeyExists } return false, nil, err } } else { // Node Exists error (when previous nil) if err == zk.ErrNodeExists { return false, nil, store.ErrKeyExists } // Unhandled error return false, nil, err } } lastIndex = 0 // Newly created nodes have version 0. } pair := &store.KVPair{ Key: key, Value: value, LastIndex: lastIndex, } return true, pair, nil } // AtomicDelete deletes a value at "key" if the key // has not been modified in the meantime, throws an // error if this is the case func (s *Zookeeper) AtomicDelete(key string, previous *store.KVPair) (bool, error) { if previous == nil { return false, store.ErrPreviousNotSpecified } err := s.client.Delete(s.normalize(key), int32(previous.LastIndex)) if err != nil { // Key not found if err == zk.ErrNoNode { return false, store.ErrKeyNotFound } // Compare failed if err == zk.ErrBadVersion { return false, store.ErrKeyModified } // General store error return false, err } return true, nil } // NewLock returns a handle to a lock struct which can // be used to provide mutual exclusion on a key func (s *Zookeeper) NewLock(key string, options *store.LockOptions) (lock store.Locker, err error) { value := []byte("") // Apply options if options != nil { if options.Value != nil { value = options.Value } } lock = &zookeeperLock{ client: s.client, key: s.normalize(key), value: value, lock: zk.NewLock(s.client, s.normalize(key), zk.WorldACL(zk.PermAll)), } return lock, err } // Lock attempts to acquire the lock and blocks while // doing so. It returns a channel that is closed if our // lock is lost or if an error occurs func (l *zookeeperLock) Lock(stopChan chan struct{}) (<-chan struct{}, error) { err := l.lock.Lock() if err == nil { // We hold the lock, we can set our value // FIXME: The value is left behind // (problematic for leader election) _, err = l.client.Set(l.key, l.value, -1) } return make(chan struct{}), err } // Unlock the "key". Calling unlock while // not holding the lock will throw an error func (l *zookeeperLock) Unlock() error { return l.lock.Unlock() } // Close closes the client connection func (s *Zookeeper) Close() { s.client.Close() } // Normalize the key for usage in Zookeeper func (s *Zookeeper) normalize(key string) string { key = store.Normalize(key) return strings.TrimSuffix(key, "/") } libkv-0.1.0/store/zookeeper/zookeeper_test.go000066400000000000000000000017211261675717100213650ustar00rootroot00000000000000package zookeeper import ( "testing" "time" "github.com/docker/libkv" "github.com/docker/libkv/store" "github.com/docker/libkv/testutils" "github.com/stretchr/testify/assert" ) var ( client = "localhost:2181" ) func makeZkClient(t *testing.T) store.Store { kv, err := New( []string{client}, &store.Config{ ConnectionTimeout: 3 * time.Second, }, ) if err != nil { t.Fatalf("cannot create store: %v", err) } return kv } func TestRegister(t *testing.T) { Register() kv, err := libkv.NewStore(store.ZK, []string{client}, nil) assert.NoError(t, err) assert.NotNil(t, kv) if _, ok := kv.(*Zookeeper); !ok { t.Fatal("Error registering and initializing zookeeper") } } func TestZkStore(t *testing.T) { kv := makeZkClient(t) ttlKV := makeZkClient(t) testutils.RunTestCommon(t, kv) testutils.RunTestAtomic(t, kv) testutils.RunTestWatch(t, kv) testutils.RunTestLock(t, kv) testutils.RunTestTTL(t, kv, ttlKV) testutils.RunCleanup(t, kv) } libkv-0.1.0/testutils/000077500000000000000000000000001261675717100146745ustar00rootroot00000000000000libkv-0.1.0/testutils/utils.go000066400000000000000000000352161261675717100163720ustar00rootroot00000000000000package testutils import ( "fmt" "testing" "time" "github.com/docker/libkv/store" "github.com/stretchr/testify/assert" ) // RunTestCommon tests the minimal required APIs which // should be supported by all K/V backends func RunTestCommon(t *testing.T, kv store.Store) { testPutGetDeleteExists(t, kv) testList(t, kv) testDeleteTree(t, kv) } // RunTestAtomic tests the Atomic operations by the K/V // backends func RunTestAtomic(t *testing.T, kv store.Store) { testAtomicPut(t, kv) testAtomicPutCreate(t, kv) testAtomicPutWithSlashSuffixKey(t, kv) testAtomicDelete(t, kv) } // RunTestWatch tests the watch/monitor APIs supported // by the K/V backends. func RunTestWatch(t *testing.T, kv store.Store) { testWatch(t, kv) testWatchTree(t, kv) } // RunTestLock tests the KV pair Lock/Unlock APIs supported // by the K/V backends. func RunTestLock(t *testing.T, kv store.Store) { testLockUnlock(t, kv) } // RunTestLockTTL tests the KV pair Lock with TTL APIs supported // by the K/V backends. func RunTestLockTTL(t *testing.T, kv store.Store, backup store.Store) { testLockTTL(t, kv, backup) } // RunTestTTL tests the TTL funtionality of the K/V backend. func RunTestTTL(t *testing.T, kv store.Store, backup store.Store) { testPutTTL(t, kv, backup) } func testPutGetDeleteExists(t *testing.T, kv store.Store) { // Get a not exist key should return ErrKeyNotFound pair, err := kv.Get("testPutGetDelete_not_exist_key") assert.Equal(t, store.ErrKeyNotFound, err) value := []byte("bar") for _, key := range []string{ "testPutGetDeleteExists", "testPutGetDeleteExists/", "testPutGetDeleteExists/testbar/", "testPutGetDeleteExists/testbar/testfoobar", } { failMsg := fmt.Sprintf("Fail key %s", key) // Put the key err = kv.Put(key, value, nil) assert.NoError(t, err, failMsg) // Get should return the value and an incremented index pair, err = kv.Get(key) assert.NoError(t, err, failMsg) if assert.NotNil(t, pair, failMsg) { assert.NotNil(t, pair.Value, failMsg) } assert.Equal(t, pair.Value, value, failMsg) assert.NotEqual(t, pair.LastIndex, 0, failMsg) // Exists should return true exists, err := kv.Exists(key) assert.NoError(t, err, failMsg) assert.True(t, exists, failMsg) // Delete the key err = kv.Delete(key) assert.NoError(t, err, failMsg) // Get should fail pair, err = kv.Get(key) assert.Error(t, err, failMsg) assert.Nil(t, pair, failMsg) // Exists should return false exists, err = kv.Exists(key) assert.NoError(t, err, failMsg) assert.False(t, exists, failMsg) } } func testWatch(t *testing.T, kv store.Store) { key := "testWatch" value := []byte("world") newValue := []byte("world!") // Put the key err := kv.Put(key, value, nil) assert.NoError(t, err) stopCh := make(<-chan struct{}) events, err := kv.Watch(key, stopCh) assert.NoError(t, err) assert.NotNil(t, events) // Update loop go func() { timeout := time.After(1 * time.Second) tick := time.Tick(250 * time.Millisecond) for { select { case <-timeout: return case <-tick: err := kv.Put(key, newValue, nil) if assert.NoError(t, err) { continue } return } } }() // Check for updates eventCount := 1 for { select { case event := <-events: assert.NotNil(t, event) if eventCount == 1 { assert.Equal(t, event.Key, key) assert.Equal(t, event.Value, value) } else { assert.Equal(t, event.Key, key) assert.Equal(t, event.Value, newValue) } eventCount++ // We received all the events we wanted to check if eventCount >= 4 { return } case <-time.After(4 * time.Second): t.Fatal("Timeout reached") return } } } func testWatchTree(t *testing.T, kv store.Store) { dir := "testWatchTree" node1 := "testWatchTree/node1" value1 := []byte("node1") node2 := "testWatchTree/node2" value2 := []byte("node2") node3 := "testWatchTree/node3" value3 := []byte("node3") err := kv.Put(node1, value1, nil) assert.NoError(t, err) err = kv.Put(node2, value2, nil) assert.NoError(t, err) err = kv.Put(node3, value3, nil) assert.NoError(t, err) stopCh := make(<-chan struct{}) events, err := kv.WatchTree(dir, stopCh) assert.NoError(t, err) assert.NotNil(t, events) // Update loop go func() { timeout := time.After(500 * time.Millisecond) for { select { case <-timeout: err := kv.Delete(node3) assert.NoError(t, err) return } } }() // Check for updates eventCount := 1 for { select { case event := <-events: assert.NotNil(t, event) // We received the Delete event on a child node // Exit test successfully if eventCount == 2 { return } eventCount++ case <-time.After(4 * time.Second): t.Fatal("Timeout reached") return } } } func testAtomicPut(t *testing.T, kv store.Store) { key := "testAtomicPut" value := []byte("world") // Put the key err := kv.Put(key, value, nil) assert.NoError(t, err) // Get should return the value and an incremented index pair, err := kv.Get(key) assert.NoError(t, err) if assert.NotNil(t, pair) { assert.NotNil(t, pair.Value) } assert.Equal(t, pair.Value, value) assert.NotEqual(t, pair.LastIndex, 0) // This CAS should fail: previous exists. success, _, err := kv.AtomicPut(key, []byte("WORLD"), nil, nil) assert.Error(t, err) assert.False(t, success) // This CAS should succeed success, _, err = kv.AtomicPut(key, []byte("WORLD"), pair, nil) assert.NoError(t, err) assert.True(t, success) // This CAS should fail, key exists. pair.LastIndex = 6744 success, _, err = kv.AtomicPut(key, []byte("WORLDWORLD"), pair, nil) assert.Error(t, err) assert.False(t, success) } func testAtomicPutCreate(t *testing.T, kv store.Store) { // Use a key in a new directory to ensure Stores will create directories // that don't yet exist. key := "testAtomicPutCreate/create" value := []byte("putcreate") // AtomicPut the key, previous = nil indicates create. success, _, err := kv.AtomicPut(key, value, nil, nil) assert.NoError(t, err) assert.True(t, success) // Get should return the value and an incremented index pair, err := kv.Get(key) assert.NoError(t, err) if assert.NotNil(t, pair) { assert.NotNil(t, pair.Value) } assert.Equal(t, pair.Value, value) // Attempting to create again should fail. success, _, err = kv.AtomicPut(key, value, nil, nil) assert.Error(t, store.ErrKeyExists) assert.False(t, success) // This CAS should succeed, since it has the value from Get() success, _, err = kv.AtomicPut(key, []byte("PUTCREATE"), pair, nil) assert.NoError(t, err) assert.True(t, success) } func testAtomicPutWithSlashSuffixKey(t *testing.T, kv store.Store) { k1 := "testAtomicPutWithSlashSuffixKey/key/" success, _, err := kv.AtomicPut(k1, []byte{}, nil, nil) assert.Nil(t, err) assert.True(t, success) } func testAtomicDelete(t *testing.T, kv store.Store) { key := "testAtomicDelete" value := []byte("world") // Put the key err := kv.Put(key, value, nil) assert.NoError(t, err) // Get should return the value and an incremented index pair, err := kv.Get(key) assert.NoError(t, err) if assert.NotNil(t, pair) { assert.NotNil(t, pair.Value) } assert.Equal(t, pair.Value, value) assert.NotEqual(t, pair.LastIndex, 0) tempIndex := pair.LastIndex // AtomicDelete should fail pair.LastIndex = 6744 success, err := kv.AtomicDelete(key, pair) assert.Error(t, err) assert.False(t, success) // AtomicDelete should succeed pair.LastIndex = tempIndex success, err = kv.AtomicDelete(key, pair) assert.NoError(t, err) assert.True(t, success) // Delete a non-existent key; should fail success, err = kv.AtomicDelete(key, pair) assert.Error(t, store.ErrKeyNotFound) assert.False(t, success) } func testLockUnlock(t *testing.T, kv store.Store) { key := "testLockUnlock" value := []byte("bar") // We should be able to create a new lock on key lock, err := kv.NewLock(key, &store.LockOptions{Value: value, TTL: 2 * time.Second}) assert.NoError(t, err) assert.NotNil(t, lock) // Lock should successfully succeed or block lockChan, err := lock.Lock(nil) assert.NoError(t, err) assert.NotNil(t, lockChan) // Get should work pair, err := kv.Get(key) assert.NoError(t, err) if assert.NotNil(t, pair) { assert.NotNil(t, pair.Value) } assert.Equal(t, pair.Value, value) assert.NotEqual(t, pair.LastIndex, 0) // Unlock should succeed err = lock.Unlock() assert.NoError(t, err) // Lock should succeed again lockChan, err = lock.Lock(nil) assert.NoError(t, err) assert.NotNil(t, lockChan) // Get should work pair, err = kv.Get(key) assert.NoError(t, err) if assert.NotNil(t, pair) { assert.NotNil(t, pair.Value) } assert.Equal(t, pair.Value, value) assert.NotEqual(t, pair.LastIndex, 0) err = lock.Unlock() assert.NoError(t, err) } func testLockTTL(t *testing.T, kv store.Store, otherConn store.Store) { key := "testLockTTL" value := []byte("bar") renewCh := make(chan struct{}) // We should be able to create a new lock on key lock, err := otherConn.NewLock(key, &store.LockOptions{ Value: value, TTL: 2 * time.Second, RenewLock: renewCh, }) assert.NoError(t, err) assert.NotNil(t, lock) // Lock should successfully succeed lockChan, err := lock.Lock(nil) assert.NoError(t, err) assert.NotNil(t, lockChan) // Get should work pair, err := otherConn.Get(key) assert.NoError(t, err) if assert.NotNil(t, pair) { assert.NotNil(t, pair.Value) } assert.Equal(t, pair.Value, value) assert.NotEqual(t, pair.LastIndex, 0) time.Sleep(3 * time.Second) done := make(chan struct{}) stop := make(chan struct{}) value = []byte("foobar") // Create a new lock with another connection lock, err = kv.NewLock( key, &store.LockOptions{ Value: value, TTL: 3 * time.Second, }, ) assert.NoError(t, err) assert.NotNil(t, lock) // Lock should block, the session on the lock // is still active and renewed periodically go func(<-chan struct{}) { _, _ = lock.Lock(stop) done <- struct{}{} }(done) select { case _ = <-done: t.Fatal("Lock succeeded on a key that is supposed to be locked by another client") case <-time.After(4 * time.Second): // Stop requesting the lock as we are blocked as expected stop <- struct{}{} break } // Close the connection otherConn.Close() // Force stop the session renewal for the lock close(renewCh) // Let the session on the lock expire time.Sleep(3 * time.Second) locked := make(chan struct{}) // Lock should now succeed for the other client go func(<-chan struct{}) { lockChan, err = lock.Lock(nil) assert.NoError(t, err) assert.NotNil(t, lockChan) locked <- struct{}{} }(locked) select { case _ = <-locked: break case <-time.After(4 * time.Second): t.Fatal("Unable to take the lock, timed out") } // Get should work with the new value pair, err = kv.Get(key) assert.NoError(t, err) if assert.NotNil(t, pair) { assert.NotNil(t, pair.Value) } assert.Equal(t, pair.Value, value) assert.NotEqual(t, pair.LastIndex, 0) err = lock.Unlock() assert.NoError(t, err) } func testPutTTL(t *testing.T, kv store.Store, otherConn store.Store) { firstKey := "testPutTTL" firstValue := []byte("foo") secondKey := "second" secondValue := []byte("bar") // Put the first key with the Ephemeral flag err := otherConn.Put(firstKey, firstValue, &store.WriteOptions{TTL: 2 * time.Second}) assert.NoError(t, err) // Put a second key with the Ephemeral flag err = otherConn.Put(secondKey, secondValue, &store.WriteOptions{TTL: 2 * time.Second}) assert.NoError(t, err) // Get on firstKey should work pair, err := kv.Get(firstKey) assert.NoError(t, err) assert.NotNil(t, pair) // Get on secondKey should work pair, err = kv.Get(secondKey) assert.NoError(t, err) assert.NotNil(t, pair) // Close the connection otherConn.Close() // Let the session expire time.Sleep(3 * time.Second) // Get on firstKey shouldn't work pair, err = kv.Get(firstKey) assert.Error(t, err) assert.Nil(t, pair) // Get on secondKey shouldn't work pair, err = kv.Get(secondKey) assert.Error(t, err) assert.Nil(t, pair) } func testList(t *testing.T, kv store.Store) { prefix := "testList" firstKey := "testList/first" firstValue := []byte("first") secondKey := "testList/second" secondValue := []byte("second") // Put the first key err := kv.Put(firstKey, firstValue, nil) assert.NoError(t, err) // Put the second key err = kv.Put(secondKey, secondValue, nil) assert.NoError(t, err) // List should work and return the two correct values for _, parent := range []string{prefix, prefix + "/"} { pairs, err := kv.List(parent) assert.NoError(t, err) if assert.NotNil(t, pairs) { assert.Equal(t, len(pairs), 2) } // Check pairs, those are not necessarily in Put order for _, pair := range pairs { if pair.Key == firstKey { assert.Equal(t, pair.Value, firstValue) } if pair.Key == secondKey { assert.Equal(t, pair.Value, secondValue) } } } // List should fail: the key does not exist pairs, err := kv.List("idontexist") assert.Equal(t, store.ErrKeyNotFound, err) assert.Nil(t, pairs) } func testDeleteTree(t *testing.T, kv store.Store) { prefix := "testDeleteTree" firstKey := "testDeleteTree/first" firstValue := []byte("first") secondKey := "testDeleteTree/second" secondValue := []byte("second") // Put the first key err := kv.Put(firstKey, firstValue, nil) assert.NoError(t, err) // Put the second key err = kv.Put(secondKey, secondValue, nil) assert.NoError(t, err) // Get should work on the first Key pair, err := kv.Get(firstKey) assert.NoError(t, err) if assert.NotNil(t, pair) { assert.NotNil(t, pair.Value) } assert.Equal(t, pair.Value, firstValue) assert.NotEqual(t, pair.LastIndex, 0) // Get should work on the second Key pair, err = kv.Get(secondKey) assert.NoError(t, err) if assert.NotNil(t, pair) { assert.NotNil(t, pair.Value) } assert.Equal(t, pair.Value, secondValue) assert.NotEqual(t, pair.LastIndex, 0) // Delete Values under directory `nodes` err = kv.DeleteTree(prefix) assert.NoError(t, err) // Get should fail on both keys pair, err = kv.Get(firstKey) assert.Error(t, err) assert.Nil(t, pair) pair, err = kv.Get(secondKey) assert.Error(t, err) assert.Nil(t, pair) } // RunCleanup cleans up keys introduced by the tests func RunCleanup(t *testing.T, kv store.Store) { for _, key := range []string{ "testAtomicPutWithSlashSuffixKey", "testPutGetDeleteExists", "testWatch", "testWatchTree", "testAtomicPut", "testAtomicPutCreate", "testAtomicDelete", "testLockUnlock", "testLockTTL", "testPutTTL", "testList", "testDeleteTree", } { err := kv.DeleteTree(key) assert.True(t, err == nil || err == store.ErrKeyNotFound, fmt.Sprintf("failed to delete tree key %s: %v", key, err)) err = kv.Delete(key) assert.True(t, err == nil || err == store.ErrKeyNotFound, fmt.Sprintf("failed to delete key %s: %v", key, err)) } }