pax_global_header00006660000000000000000000000064130335311300014502gustar00rootroot0000000000000052 comment=4fb5f8204f26b45ef2445bd98bc04fccf04a3e0a dlog-0.0.1/000077500000000000000000000000001303353113000124255ustar00rootroot00000000000000dlog-0.0.1/.gitignore000066400000000000000000000004121303353113000144120ustar00rootroot00000000000000# Compiled Object files, Static and Dynamic libs (Shared Objects) *.o *.a *.so # Folders _obj _test # Architecture specific extensions/prefixes *.[568vq] [568vq].out *.cgo1.go *.cgo2.c _cgo_defun.c _cgo_gotypes.go _cgo_export.* _testmain.go *.exe *.test *.prof dlog-0.0.1/.travis.yml000066400000000000000000000006101303353113000145330ustar00rootroot00000000000000sudo: false language: go go: - 1.7 before_install: - go get github.com/mattn/goveralls - go get golang.org/x/tools/cmd/cover - go get -u github.com/golang/lint/golint script: - test -z $(go vet ./...) - test -z $(golint ./...) - go test -v ./... - go test -covermode=count -coverprofile=profile.cov after_script: - goveralls -coverprofile=profile.cov -service=travis-ci dlog-0.0.1/LICENSE000066400000000000000000000261221303353113000134350ustar00rootroot00000000000000 Apache License Version 2.0, January 2004 http://www.apache.org/licenses/ TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION 1. Definitions. "License" shall mean the terms and conditions for use, reproduction, and distribution as defined by Sections 1 through 9 of this document. "Licensor" shall mean the copyright owner or entity authorized by the copyright owner that is granting the License. "Legal Entity" shall mean the union of the acting entity and all other entities that control, are controlled by, or are under common control with that entity. For the purposes of this definition, "control" means (i) the power, direct or indirect, to cause the direction or management of such entity, whether by contract or otherwise, or (ii) ownership of fifty percent (50%) or more of the outstanding shares, or (iii) beneficial ownership of such entity. "You" (or "Your") shall mean an individual or Legal Entity exercising permissions granted by this License. "Source" form shall mean the preferred form for making modifications, including but not limited to software source code, documentation source, and configuration files. 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"Contribution" shall mean any work of authorship, including the original version of the Work and any modifications or additions to that Work or Derivative Works thereof, that is intentionally submitted to Licensor for inclusion in the Work by the copyright owner or by an individual or Legal Entity authorized to submit on behalf of the copyright owner. For the purposes of this definition, "submitted" means any form of electronic, verbal, or written communication sent to the Licensor or its representatives, including but not limited to communication on electronic mailing lists, source code control systems, and issue tracking systems that are managed by, or on behalf of, the Licensor for the purpose of discussing and improving the Work, but excluding communication that is conspicuously marked or otherwise designated in writing by the copyright owner as "Not a Contribution." "Contributor" shall mean Licensor and any individual or Legal Entity on behalf of whom a Contribution has been received by Licensor and subsequently incorporated within the Work. 2. Grant of Copyright License. Subject to the terms and conditions of this License, each Contributor hereby grants to You a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license to reproduce, prepare Derivative Works of, publicly display, publicly perform, sublicense, and distribute the Work and such Derivative Works in Source or Object form. 3. Grant of Patent License. Subject to the terms and conditions of this License, each Contributor hereby grants to You a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable (except as stated in this section) patent license to make, have made, use, offer to sell, sell, import, and otherwise transfer the Work, where such license applies only to those patent claims licensable by such Contributor that are necessarily infringed by their Contribution(s) alone or by combination of their Contribution(s) with the Work to which such Contribution(s) was submitted. If You institute patent litigation against any entity (including a cross-claim or counterclaim in a lawsuit) alleging that the Work or a Contribution incorporated within the Work constitutes direct or contributory patent infringement, then any patent licenses granted to You under this License for that Work shall terminate as of the date such litigation is filed. 4. Redistribution. You may reproduce and distribute copies of the Work or Derivative Works thereof in any medium, with or without modifications, and in Source or Object form, provided that You meet the following conditions: (a) You must give any other recipients of the Work or Derivative Works a copy of this License; and (b) You must cause any modified files to carry prominent notices stating that You changed the files; and (c) You must retain, in the Source form of any Derivative Works that You distribute, all copyright, patent, trademark, and attribution notices from the Source form of the Work, excluding those notices that do not pertain to any part of the Derivative Works; and (d) If the Work includes a "NOTICE" text file as part of its distribution, then any Derivative Works that You distribute must include a readable copy of the attribution notices contained within such NOTICE file, excluding those notices that do not pertain to any part of the Derivative Works, in at least one of the following places: within a NOTICE text file distributed as part of the Derivative Works; within the Source form or documentation, if provided along with the Derivative Works; or, within a display generated by the Derivative Works, if and wherever such third-party notices normally appear. The contents of the NOTICE file are for informational purposes only and do not modify the License. You may add Your own attribution notices within Derivative Works that You distribute, alongside or as an addendum to the NOTICE text from the Work, provided that such additional attribution notices cannot be construed as modifying the License. You may add Your own copyright statement to Your modifications and may provide additional or different license terms and conditions for use, reproduction, or distribution of Your modifications, or for any such Derivative Works as a whole, provided Your use, reproduction, and distribution of the Work otherwise complies with the conditions stated in this License. 5. Submission of Contributions. Unless You explicitly state otherwise, any Contribution intentionally submitted for inclusion in the Work by You to the Licensor shall be under the terms and conditions of this License, without any additional terms or conditions. 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You are solely responsible for determining the appropriateness of using or redistributing the Work and assume any risks associated with Your exercise of permissions under this License. 8. Limitation of Liability. In no event and under no legal theory, whether in tort (including negligence), contract, or otherwise, unless required by applicable law (such as deliberate and grossly negligent acts) or agreed to in writing, shall any Contributor be liable to You for damages, including any direct, indirect, special, incidental, or consequential damages of any character arising as a result of this License or out of the use or inability to use the Work (including but not limited to damages for loss of goodwill, work stoppage, computer failure or malfunction, or any and all other commercial damages or losses), even if such Contributor has been advised of the possibility of such damages. 9. Accepting Warranty or Additional Liability. While redistributing the Work or Derivative Works thereof, You may choose to offer, and charge a fee for, acceptance of support, warranty, indemnity, or other liability obligations and/or rights consistent with this License. However, in accepting such obligations, You may act only on Your own behalf and on Your sole responsibility, not on behalf of any other Contributor, and only if You agree to indemnify, defend, and hold each Contributor harmless for any liability incurred by, or claims asserted against, such Contributor by reason of your accepting any such warranty or additional liability. END OF TERMS AND CONDITIONS APPENDIX: How to apply the Apache License to your work. To apply the Apache License to your work, attach the following boilerplate notice, with the fields enclosed by brackets "{}" replaced with your own identifying information. (Don't include the brackets!) The text should be enclosed in the appropriate comment syntax for the file format. We also recommend that a file or class name and description of purpose be included on the same "printed page" as the copyright notice for easier identification within third-party archives. Copyright 2017 Ahmet Alp Balkan Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0 Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License. dlog-0.0.1/README.md000066400000000000000000000035441303353113000137120ustar00rootroot00000000000000# dlog Go library to parse the binary Docker Logs stream into plain text. [![GoDoc](https://godoc.org/github.com/ahmetalpbalkan/dlog?status.svg)](https://godoc.org/github.com/ahmetalpbalkan/dlog) [![Build Status](https://travis-ci.org/ahmetalpbalkan/dlog.svg?branch=master)](https://travis-ci.org/ahmetalpbalkan/dlog) [![Coverage Status](https://coveralls.io/repos/github/ahmetalpbalkan/dlog/badge.svg?branch=master)](https://coveralls.io/github/ahmetalpbalkan/dlog?branch=master) [![Go Report Card](https://goreportcard.com/badge/github.com/ahmetalpbalkan/dlog)](https://goreportcard.com/report/github.com/ahmetalpbalkan/dlog) `dlog` offers a single method: `NewReader(r io.Reader) io.Reader`. You are supposed to give the response body of the `/containers//logs`. The returned reader strips off the log headers and just gives the plain text to be used. Here is how a log line from container looks like in the the raw docker logs stream: ```text 01 00 00 00 00 00 00 1f 52 6f 73 65 73 20 61 72 65 ... │ ─────┬── ─────┬───── R o s e s a r e ... │ │ │ └stdout │ │ │ └─ 0x0000001f = log message is 31 bytes unused ``` You can get the logs stream from [go-dockerclient][gocl]'s [`Logs()`][gocl-logs] method, or by calling the [container logs endpoint][rapi] direclty via the UNIX socket directly. See [`example_test.go`](./example_test.go) for an example usage. This library is written in vanilla Go and has no external dependencies. [gocl]: https://github.com/fsouza/go-dockerclient [gocl-logs]: https://godoc.org/github.com/fsouza/go-dockerclient#Client.Logs [rapi]: https://docs.docker.com/engine/reference/api/docker_remote_api_v1.24/#/get-container-logs ----- Licensed under Apache 2.0. Copyright 2017 [Ahmet Alp Balkan][ab]. [ab]: https://ahmetalpbalkan.com/ dlog-0.0.1/example_test.go000066400000000000000000000017741303353113000154570ustar00rootroot00000000000000package dlog_test import ( "bufio" "context" "fmt" "log" "net" "net/http" "github.com/ahmetalpbalkan/dlog" ) func ExampleNewReader() { client := &http.Client{ Transport: &http.Transport{ DialContext: func(ctx context.Context, network, addr string) (net.Conn, error) { conn, err := net.Dial("unix", "/var/run/docker.sock") if err != nil { return nil, fmt.Errorf("cannot connect docker socket: %v", err) } return conn, nil }}} url := "http://-/containers/CONTAINER_NAME/logs?stdout=1&stderr=1&follow=1" resp, err := client.Get(url) if err != nil { log.Fatalf("request failed: %v", err) } defer resp.Body.Close() if resp.StatusCode != http.StatusOK { log.Fatalf("unexpected status code: %s", resp.Status) } // At this point we have a logs stream, here is how to read each log line // from container: r := dlog.NewReader(resp.Body) s := bufio.NewScanner(r) for s.Scan() { log.Println(s) } if err := s.Err(); err != nil { log.Fatalf("read error: %v", err) } } dlog-0.0.1/reader.go000066400000000000000000000050701303353113000142200ustar00rootroot00000000000000// Package dlog provides utilities to read Docker Logs API stream format. package dlog import ( "encoding/binary" "fmt" "io" ) const ( // these should match https://github.com/docker/docker/blob/master/pkg/stdcopy/stdcopy.go stdWriterPrefixLen = 8 // len of header stdWriterSizeIndex = 4 // size byte index in header initialBufLen = 1024 * 2 maxMsgLen = 1024 * 64 ) type reader struct { r io.Reader // original reader // reader state inMsg bool msgLen uint32 cursor uint32 buf []byte prefixBuf []byte } // NewReader returns a reader that strips off the message headers from the // underlying raw docker logs stream and returns the messages. func NewReader(r io.Reader) io.Reader { return &reader{ r: r, prefixBuf: make([]byte, stdWriterPrefixLen), buf: make([]byte, initialBufLen)} } func (r *reader) Read(p []byte) (n int, err error) { // at the beginning of a message, parse and store the message if !r.inMsg { if err := r.parse(); err != nil { return 0, err } r.inMsg = true } n, err = r.readMsg(p) // serve from buf if err == io.EOF { err = nil // continue next msg (parse() handles the EOF from r.r) r.inMsg = false } return } func (r *reader) readMsg(p []byte) (int, error) { if r.cursor >= r.msgLen { return 0, io.EOF } n := copy(p, r.buf[r.cursor:r.msgLen]) r.cursor += uint32(n) return n, nil } func (r *reader) parse() error { n, err := io.ReadFull(r.r, r.prefixBuf) if err != nil { switch err { case io.EOF: return err // end of the underlying logs stream case io.ErrUnexpectedEOF: return fmt.Errorf("dlog: corrupted prefix. read %d bytes", n) default: return fmt.Errorf("dlog: error reading prefix: %v", err) } } if r.prefixBuf[0] != 0x1 && r.prefixBuf[0] != 0x2 { return fmt.Errorf("dlog: unexpected stream byte: %#x", r.prefixBuf[0]) } size := binary.BigEndian.Uint32(r.prefixBuf[stdWriterSizeIndex : stdWriterSizeIndex+4]) if size > maxMsgLen { // safeguard to prevent reading garbage return fmt.Errorf("dlog: parsed msg too large: %d (max: %d) suspected garbage", size, maxMsgLen) } // grow buf if necessary if int(size) > len(r.buf) { r.buf = make([]byte, size) } // read the message body into buf m, err := io.ReadFull(r.r, r.buf[:int(size)]) if err != nil { switch err { case io.EOF, io.ErrUnexpectedEOF: return fmt.Errorf("dlog: corrupt message read %d out of %d bytes: %v", m, size, err) default: return fmt.Errorf("dlog: failed to read message: %v", err) } } // reset cursors for the new message r.msgLen = size r.cursor = 0 return nil } dlog-0.0.1/reader_test.go000066400000000000000000000111231303353113000152530ustar00rootroot00000000000000package dlog_test import ( "bytes" "encoding/binary" "errors" "io" "io/ioutil" "strings" "testing" "github.com/ahmetalpbalkan/dlog" ) func Test_tooShortForPrefix(t *testing.T) { r := dlog.NewReader(strings.NewReader("123")) _, err := ioutil.ReadAll(r) if err == nil { t.Fatal("expected error") } if !strings.HasPrefix(err.Error(), "dlog: corrupted prefix") { t.Fatalf("unexpected error message: %v", err) } } func Test_corruptPrefixInMiddle(t *testing.T) { b := append(msg(1, []byte("Hi!")), []byte{0x1, 0x0, 0x0, 0x0}...) r := dlog.NewReader(bytes.NewReader(b)) _, err := ioutil.ReadAll(r) if err == nil { t.Fatal("expected error") } if !strings.HasPrefix(err.Error(), "dlog: corrupted prefix") { t.Fatalf("unexpected error message: %v", err) } } func Test_prefixReadFailure(t *testing.T) { r := dlog.NewReader( io.MultiReader( bytes.NewReader(msg(1, []byte("Hello!"))), &badReader{})) b, err := ioutil.ReadAll(r) if err == nil { t.Fatal("expected error") } if expected := "dlog: error reading prefix: phony error"; err.Error() != expected { t.Fatalf("expected: %q got: %v", expected, err) } if expected := "Hello!"; string(b) != expected { t.Fatalf("wrong partially read part. expeected %q got %q", expected, string(b)) } } func Test_unrecognizedStreamByte(t *testing.T) { r := dlog.NewReader(bytes.NewReader([]byte{0x03, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0})) _, err := ioutil.ReadAll(r) if err == nil { t.Fatal("expected error") } if expected := "dlog: unexpected stream byte: 0x3"; err.Error() != expected { t.Fatalf("expected error: %q got:%v", expected, err) } } func Test_growsInitialBuffer(t *testing.T) { m := bytes.Repeat([]byte{'A'}, 3000) // intiial buf 2048 r := dlog.NewReader(bytes.NewReader(msg(1, m))) b, err := ioutil.ReadAll(r) if err != nil { t.Fatal(err) } if !same(m, b) { t.Fatalf("wrong output: expected=(%d)%#v got=(%d)%#v", len(m), m, len(b), b) } } func Test_messageLimit_atLimit(t *testing.T) { b := append(msg(1, []byte("Hello!\n")), msg(1, bytes.Repeat([]byte{'A'}, 65536))...) // large msg but allowed 64k _, err := ioutil.ReadAll(dlog.NewReader(bytes.NewReader(b))) if err != nil { t.Fatal(err) } } func Test_messageLimit_exceeds(t *testing.T) { b := append(msg(1, []byte("hello\n")), []byte{0x1, 0x0, 0x0, 0x0 /* 65537 bytes */, 0x00, 0x01, 0x00, 0x01 /* rest must be ignored */, 0xff}...) _, err := ioutil.ReadAll(dlog.NewReader(bytes.NewReader(b))) if err == nil { t.Fatal("expected error") } if expected := "parsed msg too large"; !strings.Contains(err.Error(), expected) { t.Fatalf("expected %q got: %v", expected, err) } } func Test_corruptMessage_missingBody(t *testing.T) { b := []byte{0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x05} out, err := ioutil.ReadAll(dlog.NewReader(bytes.NewReader(b))) if err == nil { t.Fatal("expected error", out) } if expected := "dlog: corrupt message read 0 out of 5 bytes: EOF"; err.Error() != expected { t.Fatalf("expected %q got: %v", expected, err) } } func Test_corruptMessage_partialBody(t *testing.T) { b := msg(1, []byte("helloworld")) b = b[:len(b)-1] // cut off last byte out, err := ioutil.ReadAll(dlog.NewReader(bytes.NewReader(b))) if err == nil { t.Fatal("expected error", out) } if expected := "dlog: corrupt message read 9 out of 10 bytes: unexpected EOF"; err.Error() != expected { t.Fatalf("expected %q got: %v", expected, err) } } func Test_messageReadFailure(t *testing.T) { r := io.MultiReader( bytes.NewReader([]byte{0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x05}), // prefix for msg len=5 &badReader{}) out, err := ioutil.ReadAll(dlog.NewReader(r)) if err == nil { t.Fatal("expected error", out) } if expected := "dlog: failed to read message: phony error"; err.Error() != expected { t.Fatalf("expected %q got: %v", expected, err) } } func Test_twoSmallMessages_parsedCorrectly(t *testing.T) { b := append(msg(1, []byte("hello\n")), msg(2, []byte("world\n"))...) out, err := ioutil.ReadAll(dlog.NewReader(bytes.NewReader(b))) if err != nil { t.Fatal(err) } if expected := "hello\nworld\n"; string(out) != expected { t.Fatalf("wrong output: %q, expected: %q", string(out), expected) } } func msg(fd int8, b []byte) []byte { size := make([]byte, 4) binary.BigEndian.PutUint32(size, uint32(len(b))) v := []byte{byte(fd), 0x0, 0x0, 0x0} return append(append(v, size...), b...) } type badReader struct{} func (_ *badReader) Read(p []byte) (int, error) { return 0, errors.New("phony error") } func same(a, b []byte) bool { if len(a) != len(b) { return false } for i := range a { if a[i] != b[i] { return false } } return true }