move args to config package

logger package rewrite as dlog

1 files changed, 156 insertions, 0 deletions

diff --git a/internal/io/dlog/loggers/file.go b/internal/io/dlog/loggers/file.go
new file mode 100644
index 0000000..1c525c9
--- /dev/null
+++ b/internal/io/dlog/loggers/file.go
@@ -0,0 +1,156 @@
+package loggers
+
+import (
+	"bufio"
+	"context"
+	"fmt"
+	"os"
+	"runtime"
+	"sync"
+	"time"
+
+	"github.com/mimecast/dtail/internal/config"
+)
+
+type fileMessageBuf struct {
+	now     time.Time
+	message string
+}
+
+type file struct {
+	bufferCh    chan *fileMessageBuf
+	pauseCh     chan struct{}
+	resumeCh    chan struct{}
+	rotateCh    chan struct{}
+	flushCh     chan struct{}
+	lastDateStr string
+	fd          *os.File
+	writer      *bufio.Writer
+	mutex       sync.Mutex
+	started     bool
+}
+
+func newFile() *file {
+	f := file{
+		bufferCh: make(chan *fileMessageBuf, runtime.NumCPU()*100),
+		pauseCh:  make(chan struct{}),
+		resumeCh: make(chan struct{}),
+		rotateCh: make(chan struct{}),
+		flushCh:  make(chan struct{}),
+	}
+	f.getWriter(time.Now().Format("20060102"))
+	return &f
+}
+
+func (s *file) Start(ctx context.Context, wg *sync.WaitGroup) {
+	s.mutex.Lock()
+	defer s.mutex.Unlock()
+
+	// Logger already started from another Goroutine.
+	if s.started {
+		wg.Done()
+		return
+	}
+
+	pause := func(ctx context.Context) {
+		select {
+		case <-s.resumeCh:
+			return
+		case <-ctx.Done():
+			return
+		}
+	}
+
+	go func() {
+		defer wg.Done()
+
+		for {
+			select {
+			case m := <-s.bufferCh:
+				s.write(m)
+			case <-s.pauseCh:
+				pause(ctx)
+			case <-s.flushCh:
+				s.flush()
+			case <-ctx.Done():
+				s.flush()
+				s.fd.Close()
+				return
+			}
+		}
+	}()
+
+	s.started = true
+}
+
+func (s *file) Log(now time.Time, message string) {
+	s.bufferCh <- &fileMessageBuf{now, message}
+}
+
+func (s *file) LogWithColors(now time.Time, message, coloredMessage string) {
+	panic("Colors not supported in file logger")
+}
+
+func (s *file) Pause()  { s.pauseCh <- struct{}{} }
+func (s *file) Resume() { s.resumeCh <- struct{}{} }
+func (s *file) Flush()  { s.flushCh <- struct{}{} }
+
+// TODO: Test that Rotate() actually works.
+func (s *file) Rotate()           { s.rotateCh <- struct{}{} }
+func (file) SupportsColors() bool { return false }
+
+func (s *file) write(m *fileMessageBuf) {
+	select {
+	case <-s.rotateCh:
+		// Force re-opening the outfile.
+		s.lastDateStr = ""
+	default:
+	}
+
+	writer := s.getWriter(m.now.Format("20060102"))
+	writer.WriteString(m.message)
+	writer.WriteByte('\n')
+}
+
+func (s *file) getWriter(dateStr string) *bufio.Writer {
+	if s.lastDateStr == dateStr {
+		return s.writer
+	}
+
+	if _, err := os.Stat(config.Common.LogDir); os.IsNotExist(err) {
+		if err = os.MkdirAll(config.Common.LogDir, 0755); err != nil {
+			panic(err)
+		}
+	}
+
+	logFile := fmt.Sprintf("%s/%s.log", config.Common.LogDir, dateStr)
+	newFd, err := os.OpenFile(logFile, os.O_CREATE|os.O_RDWR|os.O_APPEND, 0644)
+	if err != nil {
+		panic(err)
+	}
+
+	// Close old writer.
+	if s.fd != nil {
+		s.writer.Flush()
+		s.fd.Close()
+	}
+
+	s.fd = newFd
+	s.writer = bufio.NewWriterSize(s.fd, 1)
+	s.lastDateStr = dateStr
+
+	return s.writer
+}
+
+func (s *file) flush() {
+	defer s.writer.Flush()
+
+	for {
+		select {
+		case m := <-s.bufferCh:
+			s.write(m)
+		default:
+			return
+		}
+	}
+}