diff options
Diffstat (limited to 'libpod')
| -rw-r--r-- | libpod/container_log.go | 208 | ||||
| -rw-r--r-- | libpod/events.go | 2 |
2 files changed, 209 insertions, 1 deletions
diff --git a/libpod/container_log.go b/libpod/container_log.go new file mode 100644 index 000000000..7964e4022 --- /dev/null +++ b/libpod/container_log.go @@ -0,0 +1,208 @@ +package libpod + +import ( + "fmt" + "io/ioutil" + "strings" + "sync" + "time" + + "github.com/hpcloud/tail" + "github.com/pkg/errors" + "github.com/sirupsen/logrus" +) + +const ( + // logTimeFormat is the time format used in the log. + // It is a modified version of RFC3339Nano that guarantees trailing + // zeroes are not trimmed, taken from + // https://github.com/golang/go/issues/19635 + logTimeFormat = "2006-01-02T15:04:05.000000000Z07:00" +) + +// LogOptions is the options you can use for logs +type LogOptions struct { + Details bool + Follow bool + Since time.Time + Tail uint64 + Timestamps bool + Multi bool + WaitGroup *sync.WaitGroup +} + +// LogLine describes the information for each line of a log +type LogLine struct { + Device string + ParseLogType string + Time time.Time + Msg string + CID string +} + +// Log is a runtime function that can read one or more container logs. +func (r *Runtime) Log(containers []*Container, options *LogOptions, logChannel chan *LogLine) error { + for _, ctr := range containers { + if err := ctr.ReadLog(options, logChannel); err != nil { + return err + } + } + return nil +} + +// ReadLog reads a containers log based on the input options and returns loglines over a channel +func (c *Container) ReadLog(options *LogOptions, logChannel chan *LogLine) error { + t, tailLog, err := getLogFile(c.LogPath(), options) + if err != nil { + return errors.Wrapf(err, "unable to read log file %s for %s ", c.ID(), c.LogPath()) + } + options.WaitGroup.Add(1) + if len(tailLog) > 0 { + for _, nll := range tailLog { + nll.CID = c.ID() + if nll.Since(options.Since) { + logChannel <- nll + } + } + } + + go func() { + var partial string + for line := range t.Lines { + nll, err := newLogLine(line.Text) + if err != nil { + logrus.Error(err) + continue + } + if nll.Partial() { + partial = partial + nll.Msg + continue + } else if !nll.Partial() && len(partial) > 1 { + nll.Msg = partial + partial = "" + } + nll.CID = c.ID() + if nll.Since(options.Since) { + logChannel <- nll + } + } + options.WaitGroup.Done() + }() + return nil +} + +// getLogFile returns an hp tail for a container given options +func getLogFile(path string, options *LogOptions) (*tail.Tail, []*LogLine, error) { + var ( + whence int + err error + logTail []*LogLine + ) + // whence 0=origin, 2=end + if options.Tail > 0 { + whence = 2 + logTail, err = getTailLog(path, int(options.Tail)) + if err != nil { + return nil, nil, err + } + } + seek := tail.SeekInfo{ + Offset: 0, + Whence: whence, + } + + t, err := tail.TailFile(path, tail.Config{Poll: true, Follow: options.Follow, Location: &seek, Logger: tail.DiscardingLogger}) + return t, logTail, err +} + +func getTailLog(path string, tail int) ([]*LogLine, error) { + var ( + tailLog []*LogLine + nlls []*LogLine + tailCounter int + partial string + ) + content, err := ioutil.ReadFile(path) + if err != nil { + return nil, err + } + splitContent := strings.Split(string(content), "\n") + // We read the content in reverse and add each nll until we have the same + // number of F type messages as the desired tail + for i := len(splitContent) - 1; i >= 0; i-- { + if len(splitContent[i]) == 0 { + continue + } + nll, err := newLogLine(splitContent[i]) + if err != nil { + return nil, err + } + nlls = append(nlls, nll) + if !nll.Partial() { + tailCounter = tailCounter + 1 + } + if tailCounter == tail { + break + } + } + // Now we iterate the results and assemble partial messages to become full messages + for _, nll := range nlls { + if nll.Partial() { + partial = partial + nll.Msg + } else { + nll.Msg = nll.Msg + partial + tailLog = append(tailLog, nll) + partial = "" + } + } + return tailLog, nil +} + +// String converts a logline to a string for output given whether a detail +// bool is specified. +func (l *LogLine) String(options *LogOptions) string { + var out string + if options.Multi { + cid := l.CID + if len(cid) > 12 { + cid = cid[:12] + } + out = fmt.Sprintf("%s ", cid) + } + if options.Timestamps { + out = out + fmt.Sprintf("%s ", l.Time.Format(logTimeFormat)) + } + return out + l.Msg +} + +// Since returns a bool as to whether a log line occurred after a given time +func (l *LogLine) Since(since time.Time) bool { + return l.Time.After(since) +} + +// newLogLine creates a logLine struct from a container log string +func newLogLine(line string) (*LogLine, error) { + splitLine := strings.Split(line, " ") + if len(splitLine) < 4 { + return nil, errors.Errorf("'%s' is not a valid container log line", line) + } + logTime, err := time.Parse(time.RFC3339Nano, splitLine[0]) + if err != nil { + return nil, errors.Wrapf(err, "unable to convert time %s from container log", splitLine[0]) + } + l := LogLine{ + Time: logTime, + Device: splitLine[1], + ParseLogType: splitLine[2], + Msg: strings.Join(splitLine[3:], " "), + } + return &l, nil +} + +// Partial returns a bool if the log line is a partial log type +func (l *LogLine) Partial() bool { + if l.ParseLogType == "P" { + return true + } + return false +} diff --git a/libpod/events.go b/libpod/events.go index f09529a05..139600982 100644 --- a/libpod/events.go +++ b/libpod/events.go @@ -92,5 +92,5 @@ func (r *Runtime) getTail(fromStart, stream bool) (*tail.Tail, error) { seek.Whence = 0 reopen = false } - return tail.TailFile(r.config.EventsLogFilePath, tail.Config{ReOpen: reopen, Follow: stream, Location: &seek}) + return tail.TailFile(r.config.EventsLogFilePath, tail.Config{ReOpen: reopen, Follow: stream, Location: &seek, Logger: tail.DiscardingLogger}) } |