1package agent
2
3import (
4	"log"
5
6	"github.com/hashicorp/logutils"
7)
8
9// logStream is used to stream logs to a client over IPC
10type logStream struct {
11	client streamClient
12	filter *logutils.LevelFilter
13	logCh  chan string
14	logger *log.Logger
15	seq    uint64
16}
17
18func newLogStream(client streamClient, filter *logutils.LevelFilter,
19	seq uint64, logger *log.Logger) *logStream {
20	ls := &logStream{
21		client: client,
22		filter: filter,
23		logCh:  make(chan string, 512),
24		logger: logger,
25		seq:    seq,
26	}
27	go ls.stream()
28	return ls
29}
30
31func (ls *logStream) HandleLog(l string) {
32	// Check the log level
33	if !ls.filter.Check([]byte(l)) {
34		return
35	}
36
37	// Do a non-blocking send
38	select {
39	case ls.logCh <- l:
40	default:
41		// We can't log syncronously, since we are already being invoked
42		// from the logWriter, and a log will need to invoke Write() which
43		// already holds the lock. We must therefor do the log async, so
44		// as to not deadlock
45		go ls.logger.Printf("[WARN] agent.ipc: Dropping logs to %v", ls.client)
46	}
47}
48
49func (ls *logStream) Stop() {
50	close(ls.logCh)
51}
52
53func (ls *logStream) stream() {
54	header := responseHeader{Seq: ls.seq, Error: ""}
55	rec := logRecord{Log: ""}
56
57	for line := range ls.logCh {
58		rec.Log = line
59		if err := ls.client.Send(&header, &rec); err != nil {
60			ls.logger.Printf("[ERR] agent.ipc: Failed to stream log to %v: %v",
61				ls.client, err)
62			return
63		}
64	}
65}
66