Add built-in console log formatter.

console_formatter.go

@@ -0,0 +1,54 @@
+package logger
+
+import (
+	"bytes"
+
+	"github.com/edoger/zkits-logger/internal"
+)
+
+// NewConsoleFormatter creates and returns an instance of the log console formatter.
+// The console formatter is very similar to the text formatter. The only difference is that
+// we output different console colors for different log levels, which is very useful when
+// outputting logs from the console.
+func NewConsoleFormatter() Formatter {
+	return new(consoleFormatter)
+}
+
+// The built-in console formatter.
+type consoleFormatter struct{}
+
+// Format formats the given log entity into character data and writes it to the given buffer.
+func (f *consoleFormatter) Format(e Entity, b *bytes.Buffer) (err error) {
+	if name := e.Name(); name == "" {
+		b.WriteString("[" + e.TimeString() + "]")
+	} else {
+		b.WriteString(name + " [" + e.TimeString() + "]")
+	}
+	switch e.Level() {
+	case TraceLevel:
+		b.WriteString("[\u001B[36m" + e.Level().ShortCapitalString() + "\u001B[0m] ") // cyan
+	case DebugLevel:
+		b.WriteString("[\u001B[96m" + e.Level().ShortCapitalString() + "\u001B[0m] ") // hi-intensity cyan
+	case InfoLevel:
+		b.WriteString("[\u001B[92m" + e.Level().ShortCapitalString() + "\u001B[0m] ") // hi-intensity green
+	case WarnLevel:
+		b.WriteString("[\u001B[93m" + e.Level().ShortCapitalString() + "\u001B[0m] ") // hi-intensity yellow
+	case ErrorLevel:
+		b.WriteString("[\u001B[95m" + e.Level().ShortCapitalString() + "\u001B[0m] ") // hi-intensity red
+	case FatalLevel:
+		b.WriteString("[\u001B[31m" + e.Level().ShortCapitalString() + "\u001B[0m] ") // magenta
+	case PanicLevel:
+		b.WriteString("[\u001B[91m" + e.Level().ShortCapitalString() + "\u001B[0m] ") // hi-intensity magenta
+	default:
+		b.WriteString("[" + e.Level().ShortCapitalString() + "] ") // no color
+	}
+	b.WriteString(e.Message())
+	if caller := e.Caller(); caller != "" {
+		b.WriteString(" " + caller)
+	}
+	if fields := e.Fields(); len(fields) > 0 {
+		b.WriteString(" " + internal.FormatFieldsToText(e.Fields()))
+	}
+	b.WriteByte('\n')
+	return
+}

console_formatter_caller_test.go

@@ -0,0 +1,23 @@
+package logger
+
+import (
+	"bytes"
+	"fmt"
+	"strconv"
+	"testing"
+)
+
+func TestConsoleFormatter_Format_WithoutCaller(t *testing.T) {
+	l := New("")
+	l.SetFormatter(NewConsoleFormatter())
+	l.SetDefaultTimeFormat("TIME")
+	buf := new(bytes.Buffer)
+	l.SetOutput(buf)
+
+	l.WithField("foo", 1).WithCaller().Trace("test") // LINE 17
+	fmt.Println(buf.String())
+	want := "[TIME][\u001B[36mTAC\u001B[0m] test console_formatter_caller_test.go:17 foo=1\n"
+	if want != buf.String() {
+		t.Fatalf("NewConsoleFormatter().Format(): %s", strconv.Quote(buf.String()))
+	}
+}

console_formatter_test.go

@@ -0,0 +1,61 @@
+package logger
+
+import (
+	"bytes"
+	"fmt"
+	"strconv"
+	"strings"
+	"testing"
+)
+
+func TestNewConsoleFormatter(t *testing.T) {
+	if f := NewConsoleFormatter(); f == nil {
+		t.Fatal("NewConsoleFormatter(): return nil.")
+	}
+}
+
+func TestConsoleFormatter_Format(t *testing.T) {
+	l := New("CONSOLE")
+	l.SetFormatter(NewConsoleFormatter())
+	l.SetDefaultTimeFormat("TIME")
+	l.SetExitFunc(nil)
+	l.SetPanicFunc(nil)
+	buf := new(bytes.Buffer)
+	l.SetOutput(buf)
+
+	l.WithField("foo", 1).Trace("test")
+	l.WithField("foo", 1).Debug("test")
+	l.WithField("foo", 1).Info("test")
+	l.WithField("foo", 1).Warn("test")
+	l.WithField("foo", 1).Error("test")
+	l.WithField("foo", 1).Fatal("test")
+	l.WithField("foo", 1).Panic("test")
+	fmt.Println(buf.String())
+	lines := []string{
+		"CONSOLE [TIME][\u001B[36mTAC\u001B[0m] test foo=1",
+		"CONSOLE [TIME][\u001B[96mDBG\u001B[0m] test foo=1",
+		"CONSOLE [TIME][\u001B[92mINF\u001B[0m] test foo=1",
+		"CONSOLE [TIME][\u001B[93mWAN\u001B[0m] test foo=1",
+		"CONSOLE [TIME][\u001B[95mERR\u001B[0m] test foo=1",
+		"CONSOLE [TIME][\u001B[31mFAT\u001B[0m] test foo=1",
+		"CONSOLE [TIME][\u001B[91mPNC\u001B[0m] test foo=1",
+	}
+	if want := strings.Join(lines, "\n") + "\n"; want != buf.String() {
+		t.Fatalf("NewConsoleFormatter().Format(): %s", strconv.Quote(buf.String()))
+	}
+}
+
+func TestConsoleFormatter_Format_WithoutName(t *testing.T) {
+	l := New("")
+	l.SetFormatter(NewConsoleFormatter())
+	l.SetDefaultTimeFormat("TIME")
+	buf := new(bytes.Buffer)
+	l.SetOutput(buf)
+
+	l.WithField("foo", 1).Trace("test")
+	fmt.Println(buf.String())
+	want := "[TIME][\u001B[36mTAC\u001B[0m] test foo=1\n"
+	if want != buf.String() {
+		t.Fatalf("NewConsoleFormatter().Format(): %s", strconv.Quote(buf.String()))
+	}
+}