chore(logging): Implement early logging

agent/accumulator_test.go

@@ -3,7 +3,6 @@ package agent
 import (
 	"bytes"
 	"errors"
-	"log"
 	"os"
 	"testing"
 	"time"
@@ -49,8 +48,8 @@ func TestAddFields(t *testing.T) {
 
 func TestAccAddError(t *testing.T) {
 	errBuf := bytes.NewBuffer(nil)
-	log.SetOutput(errBuf)
-	defer log.SetOutput(os.Stderr)
+	logger.RedirectLogging(errBuf)
+	defer logger.RedirectLogging(os.Stderr)
 
 	metrics := make(chan telegraf.Metric, 10)
 	defer close(metrics)

cmd/telegraf/main.go

@@ -137,11 +137,6 @@ func runApp(args []string, outputBuffer io.Writer, pprof Server, c TelegrafConfi
 			return fmt.Errorf("unknown command %q", cCtx.Args().First())
 		}
 
-		err := logger.SetupLogging(&logger.Config{})
-		if err != nil {
-			return err
-		}
-
 		// Deprecated: Use execd instead
 		// Load external plugins, if requested.
 		if cCtx.String("plugin-directory") != "" {

config/config.go

@@ -458,11 +458,11 @@ func (c *Config) LoadConfig(path string) error {
 
 	data, _, err := LoadConfigFileWithRetries(path, c.Agent.ConfigURLRetryAttempts)
 	if err != nil {
-		return fmt.Errorf("error loading config file %s: %w", path, err)
+		return fmt.Errorf("loading config file %s failed: %w", path, err)
 	}
 
 	if err = c.LoadConfigData(data); err != nil {
-		return fmt.Errorf("error loading config file %s: %w", path, err)
+		return fmt.Errorf("loading config file %s failed: %w", path, err)
 	}
 
 	return nil

config/config_test.go

@@ -497,7 +497,7 @@ func TestConfig_BadOrdering(t *testing.T) {
 	require.Error(t, err, "bad ordering")
 	require.Equal(
 		t,
-		"error loading config file ./testdata/non_slice_slice.toml: error parsing http array, line 4: cannot unmarshal TOML array into string (need slice)",
+		"loading config file ./testdata/non_slice_slice.toml failed: error parsing http array, line 4: cannot unmarshal TOML array into string (need slice)",
 		err.Error(),
 	)
 }
@@ -541,11 +541,11 @@ func TestConfig_URLLikeFileName(t *testing.T) {
 		// The error file not found error message is different on Windows
 		require.Equal(
 			t,
-			"error loading config file http:##www.example.com.conf: open http:##www.example.com.conf: The system cannot find the file specified.",
+			"loading config file http:##www.example.com.conf failed: open http:##www.example.com.conf: The system cannot find the file specified.",
 			err.Error(),
 		)
 	} else {
-		require.Equal(t, "error loading config file http:##www.example.com.conf: open http:##www.example.com.conf: no such file or directory", err.Error())
+		require.Equal(t, "loading config file http:##www.example.com.conf failed: open http:##www.example.com.conf: no such file or directory", err.Error())
 	}
 }
 

config/internal_test.go

@@ -383,7 +383,7 @@ func TestURLRetries3Fails(t *testing.T) {
 	}))
 	defer ts.Close()
 
-	expected := fmt.Sprintf("error loading config file %s: failed to fetch HTTP config: 404 Not Found", ts.URL)
+	expected := fmt.Sprintf("loading config file %s failed: failed to fetch HTTP config: 404 Not Found", ts.URL)
 
 	c := NewConfig()
 	err := c.LoadConfig(ts.URL)

docs/LICENSE_OF_DEPENDENCIES.md

@@ -212,7 +212,6 @@ following works:
 - github.com/influxdata/line-protocol [MIT License](https://github.com/influxdata/line-protocol/blob/v2/LICENSE)
 - github.com/influxdata/tail [MIT License](https://github.com/influxdata/tail/blob/master/LICENSE.txt)
 - github.com/influxdata/toml [MIT License](https://github.com/influxdata/toml/blob/master/LICENSE)
-- github.com/influxdata/wlog [MIT License](https://github.com/influxdata/wlog/blob/master/LICENSE)
 - github.com/intel/iaevents [Apache License 2.0](https://github.com/intel/iaevents/blob/main/LICENSE)
 - github.com/intel/powertelemetry [Apache License 2.0](https://github.com/intel/powertelemetry/blob/main/LICENSE)
 - github.com/jackc/chunkreader [MIT License](https://github.com/jackc/chunkreader/blob/master/LICENSE)

go.mod

@@ -114,7 +114,6 @@ require (
 	github.com/influxdata/line-protocol/v2 v2.2.1
 	github.com/influxdata/tail v1.0.1-0.20221130111531-19b97bffd978
 	github.com/influxdata/toml v0.0.0-20190415235208-270119a8ce65
-	github.com/influxdata/wlog v0.0.0-20160411224016-7c63b0a71ef8
 	github.com/intel/iaevents v1.1.0
 	github.com/intel/powertelemetry v1.0.1
 	github.com/jackc/pgconn v1.14.3

go.sum

@@ -1621,8 +1621,6 @@ github.com/influxdata/tail v1.0.1-0.20221130111531-19b97bffd978 h1:SaKzm7QUHJcHO
 github.com/influxdata/tail v1.0.1-0.20221130111531-19b97bffd978/go.mod h1:VeiWgI3qaGdJWust2fP27a6J+koITo/1c/UhxeOxgaM=
 github.com/influxdata/toml v0.0.0-20190415235208-270119a8ce65 h1:vvyMtD5LTJc1W9sQKjDkAWdcg0478CszSdzlHtiAXCY=
 github.com/influxdata/toml v0.0.0-20190415235208-270119a8ce65/go.mod h1:zApaNFpP/bTpQItGZNNUMISDMDAnTXu9UqJ4yT3ocz8=
-github.com/influxdata/wlog v0.0.0-20160411224016-7c63b0a71ef8 h1:W2IgzRCb0L9VzMujq/QuTaZUKcH8096jWwP519mHN6Q=
-github.com/influxdata/wlog v0.0.0-20160411224016-7c63b0a71ef8/go.mod h1:/2NMgWB1DHM1ti/gqhOlg+LJeBVk6FqR5aVGYY0hlwI=
 github.com/intel/iaevents v1.1.0 h1:FzxMBfXk/apG2EUXUCfaq3gUQ+q+TgZ1HNMjjUILUGE=
 github.com/intel/iaevents v1.1.0/go.mod h1:CyUUzXw0lHRCsmyyF7Pwco9Y7NiTNQUUlcJ7RJAazKs=
 github.com/intel/powertelemetry v1.0.1 h1:a35pZbqOnJlEYGEPXM+YKtetu6D6dJD4Jb4GS4Zetxs=

logger.go

@@ -3,6 +3,19 @@ package telegraf
 // LogLevel denotes the level for logging
 type LogLevel int
 
+const (
+	// None means nothing is logged
+	None LogLevel = iota
+	// Error will log error messages
+	Error
+	// Warn will log error messages and warnings
+	Warn
+	// Info will log error messages, warnings and information messages
+	Info
+	// Debug will log all of the above and debugging messages issued by plugins
+	Debug
+)
+
 func (e LogLevel) String() string {
 	switch e {
 	case Error:
@@ -17,18 +30,19 @@ func (e LogLevel) String() string {
 	return "NONE"
 }
 
-const (
-	// None means nothing is logged
-	None LogLevel = iota
-	// Error will log error messages
-	Error
-	// Warn will log error messages and warnings
-	Warn
-	// Info will log error messages, warnings and information messages
-	Info
-	// Debug will log all of the above and debugging messages issued by plugins
-	Debug
-)
+func (e LogLevel) Indicator() string {
+	switch e {
+	case Error:
+		return "E!"
+	case Warn:
+		return "W!"
+	case Info:
+		return "I!"
+	case Debug:
+		return "D!"
+	}
+	return "U!"
+}
 
 // Logger defines an plugin-related interface for logging.
 type Logger interface {

logger/default_logger.go

@@ -2,6 +2,7 @@ package logger
 
 import (
 	"errors"
+	"fmt"
 	"io"
 	"log"
 	"os"
@@ -10,7 +11,6 @@ import (
 
 	"github.com/influxdata/telegraf"
 	"github.com/influxdata/telegraf/internal/rotate"
-	"github.com/influxdata/wlog"
 )
 
 const (
@@ -19,141 +19,110 @@ const (
 )
 
 type defaultLogger struct {
-	Category string
-	Name     string
-	Alias    string
-	LogLevel telegraf.LogLevel
-
 	prefix  string
 	onError []func()
 
-	writer         io.Writer
-	internalWriter io.Writer
-	timezone       *time.Location
-}
-
-func (t *defaultLogger) Write(b []byte) (n int, err error) {
-	var line []byte
-	timeToPrint := time.Now().In(t.timezone)
-
-	if !prefixRegex.Match(b) {
-		line = append([]byte(timeToPrint.Format(time.RFC3339)+" I! "), b...)
-	} else {
-		line = append([]byte(timeToPrint.Format(time.RFC3339)+" "), b...)
-	}
-
-	return t.writer.Write(line)
+	logger   *log.Logger
+	level    telegraf.LogLevel
+	timezone *time.Location
 }
 
 // NewLogger creates a new logger instance
-func (t *defaultLogger) New(category, name, alias string) telegraf.Logger {
-	var prefix string
-	if category != "" {
-		prefix = "[" + category
-		if name != "" {
-			prefix += "." + name
-		}
-		if alias != "" {
-			prefix += "::" + alias
-		}
-		prefix += "] "
+func (l *defaultLogger) New(tag string) telegraf.Logger {
+	prefix := l.prefix
+	if prefix != "" && tag != "" {
+		prefix += "." + tag
+	} else {
+		prefix = tag
 	}
-
 	return &defaultLogger{
-		Category:       category,
-		Name:           name,
-		Alias:          alias,
-		LogLevel:       t.LogLevel,
-		prefix:         prefix,
-		writer:         t.writer,
-		internalWriter: t.internalWriter,
-		timezone:       t.timezone,
+		prefix:   prefix,
+		level:    l.level,
+		logger:   l.logger,
+		timezone: l.timezone,
 	}
 }
 
-func (t *defaultLogger) Close() error {
-	// avoid closing stderr
-	if t.internalWriter == os.Stderr {
+func (l *defaultLogger) Close() error {
+	writer := l.logger.Writer()
+
+	// Close the writer if possible and avoid closing stderr
+	if writer == os.Stderr {
 		return nil
 	}
-
-	closer, isCloser := t.internalWriter.(io.Closer)
-	if !isCloser {
-		return errors.New("the underlying writer cannot be closed")
+	if closer, ok := writer.(io.Closer); ok {
+		return closer.Close()
 	}
-	return closer.Close()
+
+	return errors.New("the underlying writer cannot be closed")
 }
 
-// OnErr defines a callback that triggers only when errors are about to be written to the log
-func (t *defaultLogger) RegisterErrorCallback(f func()) {
-	t.onError = append(t.onError, f)
+// Register a callback triggered when errors are about to be written to the log
+func (l *defaultLogger) RegisterErrorCallback(f func()) {
+	l.onError = append(l.onError, f)
 }
 
-func (t *defaultLogger) Level() telegraf.LogLevel {
-	return t.LogLevel
+func (l *defaultLogger) SetOutput(w io.Writer) {
+	l.logger.SetOutput(w)
 }
 
-// Errorf logs an error message, patterned after log.Printf.
-func (t *defaultLogger) Errorf(format string, args ...interface{}) {
-	log.Printf("E! "+t.prefix+format, args...)
-	for _, f := range t.onError {
-		f()
-	}
+func (l *defaultLogger) Level() telegraf.LogLevel {
+	return l.level
+}
+
+// Error logging including callbacks
+func (l *defaultLogger) Errorf(format string, args ...interface{}) {
+	l.Error(fmt.Sprintf(format, args...))
 }
 
-// Error logs an error message, patterned after log.Print.
-func (t *defaultLogger) Error(args ...interface{}) {
-	for _, f := range t.onError {
+func (l *defaultLogger) Error(args ...interface{}) {
+	l.Print(telegraf.Error, time.Now(), args...)
+	for _, f := range l.onError {
 		f()
 	}
-	log.Print(append([]interface{}{"E! " + t.prefix}, args...)...)
 }
 
-// Debugf logs a debug message, patterned after log.Printf.
-func (t *defaultLogger) Debugf(format string, args ...interface{}) {
-	log.Printf("D! "+t.prefix+" "+format, args...)
+// Warning logging
+func (l *defaultLogger) Warnf(format string, args ...interface{}) {
+	l.Warn(fmt.Sprintf(format, args...))
 }
 
-// Debug logs a debug message, patterned after log.Print.
-func (t *defaultLogger) Debug(args ...interface{}) {
-	log.Print(append([]interface{}{"D! " + t.prefix}, args...)...)
+func (l *defaultLogger) Warn(args ...interface{}) {
+	l.Print(telegraf.Warn, time.Now(), args...)
 }
 
-// Warnf logs a warning message, patterned after log.Printf.
-func (t *defaultLogger) Warnf(format string, args ...interface{}) {
-	log.Printf("W! "+t.prefix+format, args...)
+// Info logging
+func (l *defaultLogger) Infof(format string, args ...interface{}) {
+	l.Info(fmt.Sprintf(format, args...))
 }
 
-// Warn logs a warning message, patterned after log.Print.
-func (t *defaultLogger) Warn(args ...interface{}) {
-	log.Print(append([]interface{}{"W! " + t.prefix}, args...)...)
+func (l *defaultLogger) Info(args ...interface{}) {
+	l.Print(telegraf.Info, time.Now(), args...)
 }
 
-// Infof logs an information message, patterned after log.Printf.
-func (t *defaultLogger) Infof(format string, args ...interface{}) {
-	log.Printf("I! "+t.prefix+format, args...)
+// Debug logging, this is suppressed on console
+func (l *defaultLogger) Debugf(format string, args ...interface{}) {
+	l.Debug(fmt.Sprintf(format, args...))
 }
 
-// Info logs an information message, patterned after log.Print.
-func (t *defaultLogger) Info(args ...interface{}) {
-	log.Print(append([]interface{}{"I! " + t.prefix}, args...)...)
+func (l *defaultLogger) Debug(args ...interface{}) {
+	l.Print(telegraf.Debug, time.Now(), args...)
 }
 
-func createDefaultLogger(cfg *Config) (logger, error) {
-	log.SetFlags(0)
-
-	// Set the log-level
-	switch cfg.logLevel {
-	case telegraf.Error:
-		wlog.SetLevel(wlog.ERROR)
-	case telegraf.Warn:
-		wlog.SetLevel(wlog.WARN)
-	case telegraf.Info:
-		wlog.SetLevel(wlog.INFO)
-	case telegraf.Debug:
-		wlog.SetLevel(wlog.DEBUG)
+func (l *defaultLogger) Print(level telegraf.LogLevel, ts time.Time, args ...interface{}) {
+	// Skip all messages with insufficient log-levels
+	if level > l.level {
+		return
+	}
+	var prefix string
+	if l.prefix != "" {
+		prefix = "[" + l.prefix + "] "
 	}
+	msg := append([]interface{}{ts.In(l.timezone).Format(time.RFC3339), " ", level.Indicator(), " ", prefix}, args...)
+	l.logger.Print(msg...)
+}
 
+func createDefaultLogger(cfg *Config) (logger, error) {
 	// Setup the writer target
 	var writer io.Writer = os.Stderr
 	if cfg.LogTarget == "file" && cfg.Logfile != "" {
@@ -181,12 +150,11 @@ func createDefaultLogger(cfg *Config) (logger, error) {
 
 	// Setup the logger
 	l := &defaultLogger{
-		writer:         wlog.NewWriter(writer),
-		internalWriter: writer,
-		timezone:       tz,
+		level:    cfg.logLevel,
+		logger:   log.New(writer, "", 0),
+		timezone: tz,
 	}
 
-	log.SetOutput(l)
 	return l, nil
 }