1 files changed, 272 insertions, 0 deletions
diff --git a/internal/io/dlog/dlog.go b/internal/io/dlog/dlog.go
new file mode 100644
index 0000000..5e0c3a1
--- /dev/null
+++ b/internal/io/dlog/dlog.go
@@ -0,0 +1,272 @@
+package dlog
+
+import (
+	"context"
+	"fmt"
+	"io/ioutil"
+	"os"
+	"path/filepath"
+	"runtime"
+	"strconv"
+	"strings"
+	"sync"
+	"time"
+
+	"github.com/mimecast/dtail/internal/color/brush"
+	"github.com/mimecast/dtail/internal/config"
+	"github.com/mimecast/dtail/internal/io/dlog/loggers"
+	"github.com/mimecast/dtail/internal/io/pool"
+	"github.com/mimecast/dtail/internal/protocol"
+	"github.com/mimecast/dtail/internal/source"
+)
+
+// Client is the log handler for the client packages.
+var Client *DLog
+
+// Server is the log handler for the server packages.
+var Server *DLog
+
+// Common is the log handler for all other packages.
+var Common *DLog
+
+var mutex sync.Mutex
+var started bool
+
+// Start logger(s).
+func Start(ctx context.Context, wg *sync.WaitGroup, sourceProcess source.Source) {
+	mutex.Lock()
+	defer mutex.Unlock()
+
+	if started {
+		Common.FatalPanic("Logger already started")
+	}
+
+	Client = new(sourceProcess, source.Client)
+	Server = new(sourceProcess, source.Server)
+	Common = Client
+	if sourceProcess == source.Server {
+		Common = Server
+	}
+
+	var wg2 sync.WaitGroup
+	wg2.Add(2)
+	go Client.start(ctx, &wg2)
+	go Server.start(ctx, &wg2)
+
+	go rotation(ctx)
+	go func() {
+		wg2.Wait()
+		wg.Done()
+	}()
+
+	started = true
+}
+
+// DLog is the DTail logger.
+type DLog struct {
+	logger loggers.Logger
+	// Is this a DTail server or client process logging?
+	sourceProcess source.Source
+	// Is this a DTail server or client package logging? In serverless mode
+	// the client can also execute code from the server package.
+	sourcePackage source.Source
+	// Max log level to log.
+	maxLevel level
+	// Current hostname.
+	hostname string
+}
+
+// new creates a new DTail logger.
+func new(sourceProcess, sourcePackage source.Source) *DLog {
+	hostname, err := os.Hostname()
+	if err != nil {
+		panic(err)
+	}
+	logRotation := loggers.NewStrategy(config.Common.LogRotation)
+	loggerName := config.Common.Logger
+	level := newLevel(config.Common.LogLevel)
+
+	return &DLog{
+		logger:        loggers.Factory(sourceProcess.String(), loggerName, logRotation),
+		sourceProcess: sourceProcess,
+		sourcePackage: sourcePackage,
+		maxLevel:      level,
+		hostname:      hostname,
+	}
+}
+
+func (d *DLog) start(ctx context.Context, wg *sync.WaitGroup) {
+	defer wg.Done()
+	var wg2 sync.WaitGroup
+	wg2.Add(1)
+	d.logger.Start(ctx, &wg2)
+	<-ctx.Done()
+	wg2.Wait()
+}
+
+func (d *DLog) log(level level, args []interface{}) string {
+	if d.maxLevel < level {
+		return ""
+	}
+	sb := pool.BuilderBuffer.Get().(*strings.Builder)
+	defer pool.RecycleBuilderBuffer(sb)
+	now := time.Now()
+
+	switch d.sourceProcess {
+	case source.Client:
+		sb.WriteString(d.sourcePackage.String())
+		sb.WriteString(protocol.FieldDelimiter)
+		sb.WriteString(d.hostname)
+		sb.WriteString(protocol.FieldDelimiter)
+		sb.WriteString(level.String())
+	default:
+		sb.WriteString(level.String())
+		sb.WriteString(protocol.FieldDelimiter)
+		sb.WriteString(now.Format("20060102-150405"))
+	}
+	sb.WriteString(protocol.FieldDelimiter)
+	d.writeArgStrings(sb, args)
+
+	message := sb.String()
+	if !config.Client.TermColorsEnable || !d.logger.SupportsColors() {
+		d.logger.Log(now, message)
+		return message
+	}
+
+	d.logger.LogWithColors(now, message, brush.Colorfy(message))
+	return message
+}
+
+func (d *DLog) writeArgStrings(sb *strings.Builder, args []interface{}) {
+	for i, arg := range args {
+		if i > 0 {
+			sb.WriteString(protocol.FieldDelimiter)
+		}
+		switch v := arg.(type) {
+		case string:
+			sb.WriteString(v)
+		case error:
+			sb.WriteString(v.Error())
+		default:
+			sb.WriteString(fmt.Sprintf("%v", v))
+		}
+	}
+}
+
+// FatalPanic terminates the process with a fatal error.
+func (d *DLog) FatalPanic(args ...interface{}) {
+	d.log(Fatal, args)
+	d.Flush()
+
+	var sb strings.Builder
+	d.writeArgStrings(&sb, args)
+	panic(sb.String())
+}
+
+// Fatal logs a fatal error.
+func (d *DLog) Fatal(args ...interface{}) string {
+	return d.log(Fatal, args)
+}
+
+// Error logging.
+func (d *DLog) Error(args ...interface{}) string {
+	return d.log(Error, args)
+}
+
+// Warn logs a warning message.
+func (d *DLog) Warn(args ...interface{}) string {
+	return d.log(Warn, args)
+}
+
+// Info logging.
+func (d *DLog) Info(args ...interface{}) string {
+	return d.log(Info, args)
+}
+
+// Verbose logging.
+func (d *DLog) Verbose(args ...interface{}) string {
+	return d.log(Verbose, args)
+}
+
+// Debug logging.
+func (d *DLog) Debug(args ...interface{}) string {
+	return d.log(Debug, args)
+}
+
+// Trace logging.
+func (d *DLog) Trace(args ...interface{}) string {
+	_, file, line, _ := runtime.Caller(1)
+	args = append(args, fmt.Sprintf("at %s:%d", file, line))
+	return d.log(Trace, args)
+}
+
+// Devel used for development purpose only logging (e.g. "print" debugging).
+func (d *DLog) Devel(args ...interface{}) string {
+	_, file, line, _ := runtime.Caller(1)
+	args = append(args, fmt.Sprintf("at %s:%d", file, line))
+	return d.log(Devel, args)
+}
+
+// Raw message logging.
+func (d *DLog) Raw(message string) string {
+	if !config.Client.TermColorsEnable || !d.logger.SupportsColors() {
+		d.logger.Log(time.Now(), message)
+		return message
+	}
+	d.logger.LogWithColors(time.Now(), message, brush.Colorfy(message))
+	return message
+}
+
+// Mapreduce logging.
+func (d *DLog) Mapreduce(table string, data map[string]interface{}) string {
+	args := make([]interface{}, len(data)+1)
+
+	if d.sourceProcess == source.Server {
+		// level|date-time|process|caller|cpus|goroutines|cgocalls|loadavg|uptime|MAPREDUCE:TABLE|key=value|...
+
+		var loadAvg string
+		if loadAvgBytes, err := ioutil.ReadFile("/proc/loadavg"); err == nil {
+			tmp := string(loadAvgBytes)
+			s := strings.SplitN(tmp, " ", 2)
+			loadAvg = s[0]
+		}
+
+		var uptime string
+		if uptimeBytes, err := ioutil.ReadFile("/proc/uptime"); err == nil {
+			tmp := string(uptimeBytes)
+			s := strings.SplitN(tmp, ".", 2)
+			i, _ := strconv.ParseInt(s[0], 10, 64)
+			t := time.Duration(i) * time.Second
+			uptime = fmt.Sprintf("%v", t)
+		}
+
+		_, file, line, _ := runtime.Caller(1)
+		args[0] = fmt.Sprintf("%d|%s:%d|%d|%d|%d|%s|%s|MAPREDUCE:%s",
+			os.Getpid(),
+			filepath.Base(file), line,
+			runtime.NumCPU(),
+			runtime.NumGoroutine(),
+			runtime.NumCgoCall(),
+			loadAvg,
+			uptime,
+			strings.ToUpper(table))
+	} else {
+		args[0] = fmt.Sprintf("STATS:%s", strings.ToUpper(table))
+	}
+
+	i := 1
+	for k, v := range data {
+		args[i] = fmt.Sprintf("%s=%v", k, v)
+		i++
+	}
+	return d.log(Info, args)
+}
+
+// Flush the log buffers.
+func (d *DLog) Flush() { d.logger.Flush() }
+
+// Pause the logging.
+func (d *DLog) Pause() { d.logger.Pause() }
+
+// Resume the logging.
+func (d *DLog) Resume() { d.logger.Resume() }