func TestClose(t *testing.T) { var buff bytes.Buffer log.SetOutput(&buff) log.SetLogLevel(log.LevelAll) err := log.Close() // should have no effect, because Buffer is not a WriteCloser if err != nil { t.Errorf("Close shouldn't have returned error: %s", err) } log.Info("Hello") if !strings.Contains(buff.String(), "Hello") { t.Errorf("Close killed output of Buffer: %s", buff.String()) } read, write := io.Pipe() log.SetOutput(write) go func() { // we need to read before writing to the pipe b := make([]byte, 100) n, err := read.Read(b) if !strings.Contains(string(b), "Hello") { t.Errorf("Pipe read failed: %d, %s, %v", n, string(b), err) } n, err = read.Read(b) if n != 0 || err != io.EOF { t.Errorf("Close didn't work: %d bytes read, %s (%v)", n, string(b), err) } }() log.Info("Hello") err = log.Close() if err != nil { t.Errorf("Close shouldn't have returned error on pipe: %s", err) } log.Info("Hello") }
// Example of using the global log. func Example() { log.SetOutput(os.Stdout) log.SetLogLevel(log.LevelAll ^ log.LevelDebug) // we call SetTimestamp so that the timestamp will be deterministic log.SetTimestamp(func() string { return "2006-01-02T15:04:05.999999999Z" }) err := log.Debug("This will not be written") if err != nil { log.Error("Could not write DEBUG entry: %s", err) } log.Info("Hello %s", "world") // Output: 2006-01-02T15:04:05.999999999Z INFO Hello world }
func TestLog(t *testing.T) { var buff bytes.Buffer log.SetOutput(&buff) log.SetLogLevel(log.LevelAll ^ log.LevelDebug ^ log.LevelFatal) log.Debug("Hello %s", "world") // this won't get written log.Info("%s %d", "Hello world", 1234) log.Close() // should have no effect, because Buffer is not a WriteCloser log.Error("%v", struct{ s string }{"Hello world"}) log.Fatal("%v", struct{ s string }{"Hello world"}) // won't trigger or write log.Custom("TEST", "Hello world", "extra arg") // we do Panic later b := buff.String() if c := strings.Count(b, "Hello"); c != 3 { t.Errorf("Bad \"Hello\" count: %d\n%s", c, b) } if strings.Count(b, "DEBUG") != 0 { t.Error("DEBUG shouldn't have been written") } if strings.Count(b, "INFO") != 1 { t.Error("INFO wasn't written") } if strings.Count(b, "ERROR") != 1 { t.Error("ERROR wasn't written") } if strings.Count(b, "FATAL") != 0 { t.Error("FATAL shouldn't have been written") } if strings.Count(b, "TEST") != 1 { t.Error("TEST wasn't written") } t.Log(b) buff.Truncate(0) log.SetLogLevel(log.LevelAll) defer func() { recover() if !strings.Contains(buff.String(), "Hello world 1234") { t.Errorf("Bad Panic() string: %s", buff.String()) } }() log.Panic("%s %d", "Hello world", 1234) t.Error("Panic didn't panic") }