app instance name flag and support added go-aah/aah#111

Author: jeevatkm

console_receiver_test.go

@@ -30,7 +30,7 @@ func TestConsoleLoggerTextJSON(t *testing.T) {
   log {
     receiver = "console"
     level = "debug"
-    pattern = "%time:2006-01-02 15:04:05.000 %appname %reqid %principal %level:-5 %shortfile %line %custom:- %message"
+    pattern = "%time:2006-01-02 15:04:05.000 %appname %insname %reqid %principal %level:-5 %shortfile %line %custom:- %message"
   }
   `
 	testConsoleLogger(t, textConfigStr2)
@@ -113,10 +113,12 @@ func testConsoleLogger(t *testing.T, cfgStr string) {
 	logger.Trace("I shoudn't see this msg, because standard logger level is DEBUG")
 	logger.Tracef("I shoudn't see this msg, because standard logger level is DEBUG: %v", 4)
 
-	logger.WithField("appname", "testlogapp").Debug("I would like to see this message, debug is useful for dev")
+	logger.WithField("appname", "testlogapp").WithField("insname", "app-sfo-cn-01").
+		Debug("I would like to see this message, debug is useful for dev")
 	logger.Debugf("I would like to see this message, debug is useful for %v", "dev")
 
-	logger.WithField("reqid", "40139CA6368607085BF6").Info("Yes, I would love to see")
+	logger.WithField("reqid", "40139CA6368607085BF6").WithField("insname", "app-sfo-cn-01").
+		Info("Yes, I would love to see")
 	logger.Infof("Yes, I would love to %v", "see")
 
 	logger.WithField("principal", "jeevanandam").Warn("Yes, yes it's an warning")

default_test.go

@@ -126,8 +126,18 @@ func TestDefaultContextLogging(t *testing.T) {
 
 func TestDefaultFieldsLogging(t *testing.T) {
 	_ = SetPattern("%time:2006-01-02 15:04:05.000 %level:-5 %appname %reqid %principal %message %fields")
-	WithField("appname", "value1").Info("Logging value 1")
-	WithFields(Fields{"appname": "value1", "key1": "key1value"}).Info("Logging value 1")
+
+	e1 := WithFields(Fields{"appname": "value1", "key1": "value 1"})
+	e1.Info("e1 logger")
+
+	e2 := e1.WithField("key2", "value 2")
+	e2.Info("e2 logger")
+
+	e3 := e1.WithFields(Fields{"key3": "value 3"})
+	e3.Info("e3 logger")
+
+	old := Writer()
+	SetWriter(old)
 }
 
 func testStdPanic(method, msg string) {

entry.go

@@ -8,6 +8,7 @@ import (
 	"bytes"
 	"encoding/json"
 	"fmt"
+	"strings"
 	"sync"
 	"time"
 )
@@ -24,15 +25,16 @@ type Fields map[string]interface{}
 // Entry represents a log entry and contains the timestamp when the entry
 // was created, level, etc.
 type Entry struct {
-	AppName   string    `json:"appname,omitempty"`
-	RequestID string    `json:"reqid,omitempty"`
-	Principal string    `json:"principal,omitempty"`
-	Level     level     `json:"-"`
-	Time      time.Time `json:"-"`
-	Message   string    `json:"message,omitempty"`
-	File      string    `json:"file,omitempty"`
-	Line      int       `json:"line,omitempty"`
-	Fields    Fields    `json:"fields,omitempty"`
+	AppName      string    `json:"app_name,omitempty"`
+	InstanceName string    `json:"instance_name,omitempty"`
+	RequestID    string    `json:"request_id,omitempty"`
+	Principal    string    `json:"principal,omitempty"`
+	Level        level     `json:"-"`
+	Time         time.Time `json:"-"`
+	Message      string    `json:"message,omitempty"`
+	File         string    `json:"file,omitempty"`
+	Line         int       `json:"line,omitempty"`
+	Fields       Fields    `json:"fields,omitempty"`
 
 	logger *Logger
 }
@@ -44,15 +46,22 @@ type Entry struct {
 // MarshalJSON method for formating entry to JSON.
 func (e *Entry) MarshalJSON() ([]byte, error) {
 	type alias Entry
-	return json.Marshal(&struct {
+	ne := &struct {
 		Level string `json:"level,omitempty"`
 		Time  string `json:"timestamp,omitempty"`
 		*alias
 	}{
-		Level: levelToLevelName[e.Level],
+		Level: e.Level.String(),
 		Time:  formatTime(e.Time),
 		alias: (*alias)(e),
-	})
+	}
+
+	// delete skip fields
+	for _, v := range strings.Fields("appname insname reqid principal") {
+		delete(ne.Fields, v)
+	}
+
+	return json.Marshal(ne)
 }
 
 //‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾
@@ -216,6 +225,17 @@ func (e *Entry) Reset() {
 	e.logger = nil
 }
 
+//‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾
+// Fields Unexported methods
+//___________________________________
+
+func (f Fields) str(key string) string {
+	if v, found := f[key]; found {
+		return fmt.Sprint(v)
+	}
+	return ""
+}
+
 //‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾
 // Unexported methods
 //___________________________________
@@ -224,25 +244,28 @@ func (e *Entry) output(lvl level, msg string) {
 	e.Time = time.Now()
 	e.Level = lvl
 	e.Message = msg
-	e.addFields(e.logger.ctx)
+	e.processFields()
 	e.logger.output(e)
 }
 
 func (e *Entry) addFields(fields Fields) {
 	for k, v := range fields {
-		switch k {
-		case "appname":
-			e.AppName = fmt.Sprint(v)
-		case "reqid":
-			e.RequestID = fmt.Sprint(v)
-		case "principal":
-			e.Principal = fmt.Sprint(v)
-		default:
-			e.Fields[k] = v
-		}
+		e.Fields[k] = v
 	}
 }
 
+func (e *Entry) processFields() {
+	e.addFields(e.logger.ctx)
+	e.AppName = e.Fields.str("appname")
+	e.InstanceName = e.Fields.str("insname")
+	e.RequestID = e.Fields.str("reqid")
+	e.Principal = e.Fields.str("principal")
+}
+
+func (e *Entry) isSkipField(key string) bool {
+	return (key == "appname" || key == "insname" || key == "reqid" || key == "principal")
+}
+
 func newEntry() *Entry {
 	return &Entry{
 		Fields: make(Fields),

formatter.go

@@ -7,6 +7,7 @@ package log
 import (
 	"fmt"
 	"path/filepath"
+	"strings"
 
 	"aahframework.org/essentials.v0"
 )
@@ -15,6 +16,7 @@ import (
 const (
 	FmtFlagLevel ess.FmtFlag = iota
 	FmtFlagAppName
+	FmtFlagInstanceName
 	FmtFlagRequestID
 	FmtFlagPrincipal
 	FmtFlagTime
@@ -31,6 +33,7 @@ const (
 const (
 	textFmt = "text"
 	jsonFmt = "json"
+	space   = " "
 )
 
 type (
@@ -58,7 +61,8 @@ var (
 	// FmtFlags is the list of log format flags supported by aah/log library
 	// Usage of flag order is up to format composition.
 	//    level     - outputs INFO, DEBUG, ERROR, so on
-	//    appname   - outputs Application Name (aka instance name)
+	//    appname   - outputs Application Name
+	//    insname   - outputs Application Instance Name
 	//    reqid     - outputs Request ID from HTTP header
 	//    principal - outputs Logged-In subject primary principal
 	//    level     - outputs INFO, DEBUG, ERROR, so on
@@ -73,6 +77,7 @@ var (
 	FmtFlags = map[string]ess.FmtFlag{
 		"level":     FmtFlagLevel,
 		"appname":   FmtFlagAppName,
+		"insname":   FmtFlagInstanceName,
 		"reqid":     FmtFlagRequestID,
 		"principal": FmtFlagPrincipal,
 		"time":      FmtFlagTime,
@@ -100,56 +105,48 @@ func textFormatter(flags []ess.FmtFlagPart, entry *Entry) []byte {
 	for _, part := range flags {
 		switch part.Flag {
 		case FmtFlagLevel:
-			buf.WriteString(fmt.Sprintf(part.Format, entry.Level))
-			buf.WriteByte(' ')
+			buf.WriteString(fmt.Sprintf(part.Format, entry.Level) + space)
 		case FmtFlagAppName:
 			if len(entry.AppName) > 0 {
-				buf.WriteString(entry.AppName)
-				buf.WriteByte(' ')
+				buf.WriteString(entry.AppName + space)
+			}
+		case FmtFlagInstanceName:
+			if len(entry.InstanceName) > 0 {
+				buf.WriteString(entry.InstanceName + space)
 			}
 		case FmtFlagRequestID:
 			if len(entry.RequestID) > 0 {
-				buf.WriteString(entry.RequestID)
-				buf.WriteByte(' ')
+				buf.WriteString(entry.RequestID + space)
 			}
 		case FmtFlagPrincipal:
 			if len(entry.Principal) > 0 {
-				buf.WriteString(entry.Principal)
-				buf.WriteByte(' ')
+				buf.WriteString(entry.Principal + space)
 			}
 		case FmtFlagTime:
-			buf.WriteString(entry.Time.Format(part.Format))
-			buf.WriteByte(' ')
+			buf.WriteString(entry.Time.Format(part.Format) + space)
 		case FmtFlagUTCTime:
-			buf.WriteString(entry.Time.UTC().Format(part.Format))
-			buf.WriteByte(' ')
+			buf.WriteString(entry.Time.UTC().Format(part.Format) + space)
 		case FmtFlagLongfile, FmtFlagShortfile:
 			if part.Flag == FmtFlagShortfile {
 				entry.File = filepath.Base(entry.File)
 			}
-			buf.WriteString(fmt.Sprintf(part.Format, entry.File))
-			buf.WriteByte(' ')
+			buf.WriteString(fmt.Sprintf(part.Format, entry.File) + space)
 		case FmtFlagLine:
-			buf.WriteString("L" + fmt.Sprintf(part.Format, entry.Line))
-			buf.WriteByte(' ')
+			buf.WriteString("L" + fmt.Sprintf(part.Format, entry.Line) + space)
 		case FmtFlagMessage:
-			buf.WriteString(entry.Message)
-			buf.WriteByte(' ')
+			buf.WriteString(entry.Message + space)
 		case FmtFlagCustom:
-			buf.WriteString(part.Format)
-			buf.WriteByte(' ')
+			buf.WriteString(part.Format + space)
 		case FmtFlagFields:
-			if cnt := len(entry.Fields); cnt > 0 {
-				buf.WriteString("fields[")
-				for k, v := range entry.Fields {
-					cnt--
-					buf.WriteString(fmt.Sprintf("%v: %v", k, v))
-					if cnt != 0 {
-						buf.WriteString(", ")
-					}
+			fs := make([]string, 0)
+			for k, v := range entry.Fields {
+				if !entry.isSkipField(k) {
+					fs = append(fs, fmt.Sprintf("%v: %v", k, v))
 				}
-				buf.WriteString("]")
-				buf.WriteByte(' ')
+			}
+
+			if len(fs) > 0 {
+				buf.WriteString("fields[" + strings.Join(fs, ", ") + "] ")
 			}
 		}
 	}