Add missing console file

markdessain · Aug 6, 2017 · 90fdb63 · 90fdb63
1 parent a83efb6
commit 90fdb63
Showing 1 changed file with 117 additions and 0 deletions.
diff --git a/console.go b/console.go
@@ -0,0 +1,117 @@
+package zerolog
+
+import (
+	"bytes"
+	"encoding/json"
+	"fmt"
+	"io"
+	"sort"
+	"strconv"
+	"strings"
+	"sync"
+)
+
+const (
+	cReset    = 0
+	cBold     = 1
+	cRed      = 31
+	cGreen    = 32
+	cYellow   = 33
+	cBlue     = 34
+	cMagenta  = 35
+	cCyan     = 36
+	cGray     = 37
+	cDarkGray = 90
+)
+
+var consoleBufPool = sync.Pool{
+	New: func() interface{} {
+		return bytes.NewBuffer(make([]byte, 0, 100))
+	},
+}
+
+// ConsoleWriter reads a JSON object per write operation and output an
+// optionally colored human readable version on the Out writer.
+type ConsoleWriter struct {
+	Out     io.Writer
+	NoColor bool
+}
+
+func (w ConsoleWriter) Write(p []byte) (n int, err error) {
+	var event map[string]interface{}
+	err = json.Unmarshal(p, &event)
+	if err != nil {
+		return
+	}
+	buf := consoleBufPool.Get().(*bytes.Buffer)
+	defer consoleBufPool.Put(buf)
+	lvlColor := cReset
+	level := "????"
+	if l, ok := event[LevelFieldName].(string); ok {
+		if !w.NoColor {
+			lvlColor = levelColor(l)
+		}
+		level = strings.ToUpper(l)[0:4]
+	}
+	fmt.Fprintf(buf, "%s |%s| %s",
+		colorize(event[TimestampFieldName], cDarkGray, !w.NoColor),
+		colorize(level, lvlColor, !w.NoColor),
+		colorize(event[MessageFieldName], cReset, !w.NoColor))
+	fields := make([]string, 0, len(event))
+	for field := range event {
+		switch field {
+		case LevelFieldName, TimestampFieldName, MessageFieldName:
+			continue
+		}
+		fields = append(fields, field)
+	}
+	sort.Strings(fields)
+	for _, field := range fields {
+		fmt.Fprintf(buf, " %s=", colorize(field, cCyan, !w.NoColor))
+		switch value := event[field].(type) {
+		case string:
+			if needsQuote(value) {
+				buf.WriteString(strconv.Quote(value))
+			} else {
+				buf.WriteString(value)
+			}
+		default:
+			fmt.Fprint(buf, value)
+		}
+	}
+	buf.WriteByte('\n')
+	buf.WriteTo(w.Out)
+	n = len(p)
+	return
+}
+
+func colorize(s interface{}, color int, enabled bool) string {
+	if !enabled {
+		return fmt.Sprintf("%v", s)
+	}
+	return fmt.Sprintf("\x1b[%dm%v\x1b[0m", color, s)
+}
+
+func levelColor(level string) int {
+	switch level {
+	case "debug":
+		return cGray
+	case "info":
+		return cGreen
+	case "warn":
+		return cYellow
+	case "error", "fatal", "panic":
+		return cRed
+	default:
+		return cReset
+	}
+}
+
+func needsQuote(s string) bool {
+	for i := range s {
+		if s[i] < 0x20 || s[i] > 0x7e || s[i] == '\\' || s[i] == '"' {
+			return true
+		}
+	}
+	return false
+}