|
| 1 | +package fluentd |
| 2 | + |
| 3 | +import ( |
| 4 | + "bytes" |
| 5 | + "io" |
| 6 | + "math" |
| 7 | + "net" |
| 8 | + "strconv" |
| 9 | + "strings" |
| 10 | + "text/template" |
| 11 | + |
| 12 | + "github.com/Sirupsen/logrus" |
| 13 | + "github.com/docker/docker/daemon/logger" |
| 14 | + "github.com/fluent/fluent-logger-golang/fluent" |
| 15 | +) |
| 16 | + |
| 17 | +type Fluentd struct { |
| 18 | + tag string |
| 19 | + containerID string |
| 20 | + containerName string |
| 21 | + writer *fluent.Fluent |
| 22 | +} |
| 23 | + |
| 24 | +type Receiver struct { |
| 25 | + ID string |
| 26 | + FullID string |
| 27 | + Name string |
| 28 | +} |
| 29 | + |
| 30 | +const ( |
| 31 | + name = "fluentd" |
| 32 | + defaultHostName = "localhost" |
| 33 | + defaultPort = 24224 |
| 34 | + defaultTagPrefix = "docker" |
| 35 | +) |
| 36 | + |
| 37 | +func init() { |
| 38 | + if err := logger.RegisterLogDriver(name, New); err != nil { |
| 39 | + logrus.Fatal(err) |
| 40 | + } |
| 41 | +} |
| 42 | + |
| 43 | +func parseConfig(ctx logger.Context) (string, int, string, error) { |
| 44 | + host := defaultHostName |
| 45 | + port := defaultPort |
| 46 | + tag := "docker." + ctx.ContainerID[:12] |
| 47 | + |
| 48 | + config := ctx.Config |
| 49 | + |
| 50 | + if address := config["fluentd-address"]; address != "" { |
| 51 | + if h, p, err := net.SplitHostPort(address); err != nil { |
| 52 | + if !strings.Contains(err.Error(), "missing port in address") { |
| 53 | + return "", 0, "", err |
| 54 | + } |
| 55 | + host = h |
| 56 | + } else { |
| 57 | + portnum, err := strconv.Atoi(p) |
| 58 | + if err != nil { |
| 59 | + return "", 0, "", err |
| 60 | + } |
| 61 | + host = h |
| 62 | + port = portnum |
| 63 | + } |
| 64 | + } |
| 65 | + |
| 66 | + if config["fluentd-tag"] != "" { |
| 67 | + receiver := &Receiver{ |
| 68 | + ID: ctx.ContainerID[:12], |
| 69 | + FullID: ctx.ContainerID, |
| 70 | + Name: ctx.ContainerName, |
| 71 | + } |
| 72 | + tmpl, err := template.New("tag").Parse(config["fluentd-tag"]) |
| 73 | + if err != nil { |
| 74 | + return "", 0, "", err |
| 75 | + } |
| 76 | + buf := new(bytes.Buffer) |
| 77 | + if err := tmpl.Execute(buf, receiver); err != nil { |
| 78 | + return "", 0, "", err |
| 79 | + } |
| 80 | + tag = buf.String() |
| 81 | + } |
| 82 | + |
| 83 | + return host, port, tag, nil |
| 84 | +} |
| 85 | + |
| 86 | +func New(ctx logger.Context) (logger.Logger, error) { |
| 87 | + host, port, tag, err := parseConfig(ctx) |
| 88 | + if err != nil { |
| 89 | + return nil, err |
| 90 | + } |
| 91 | + logrus.Debugf("logging driver fluentd configured for container:%s, host:%s, port:%d, tag:%s.", ctx.ContainerID, host, port, tag) |
| 92 | + |
| 93 | + // logger tries to recoonect 2**64 - 1 times |
| 94 | + // failed (and panic) after 204 years [ 1.5 ** (2**32 - 1) - 1 seconds] |
| 95 | + log, err := fluent.New(fluent.Config{FluentPort: port, FluentHost: host, RetryWait: 1000, MaxRetry: math.MaxUint32}) |
| 96 | + if err != nil { |
| 97 | + return nil, err |
| 98 | + } |
| 99 | + return &Fluentd{ |
| 100 | + tag: tag, |
| 101 | + containerID: ctx.ContainerID, |
| 102 | + containerName: ctx.ContainerName, |
| 103 | + writer: log, |
| 104 | + }, nil |
| 105 | +} |
| 106 | + |
| 107 | +func (f *Fluentd) Log(msg *logger.Message) error { |
| 108 | + data := map[string]string{ |
| 109 | + "container_id": f.containerID, |
| 110 | + "container_name": f.containerName, |
| 111 | + "source": msg.Source, |
| 112 | + "log": string(msg.Line), |
| 113 | + } |
| 114 | + // fluent-logger-golang buffers logs from failures and disconnections, |
| 115 | + // and these are transferred again automatically. |
| 116 | + return f.writer.PostWithTime(f.tag, msg.Timestamp, data) |
| 117 | +} |
| 118 | + |
| 119 | +func (f *Fluentd) Close() error { |
| 120 | + return f.writer.Close() |
| 121 | +} |
| 122 | + |
| 123 | +func (f *Fluentd) Name() string { |
| 124 | + return name |
| 125 | +} |
| 126 | + |
| 127 | +func (s *Fluentd) GetReader() (io.Reader, error) { |
| 128 | + return nil, logger.ReadLogsNotSupported |
| 129 | +} |
0 commit comments