logging: Setup accept io.Writer instead of []io.Writer

Also accept a non-pointer Config, since the config is not modified

agent/setup.go

@@ -51,7 +51,7 @@ func NewBaseDeps(configLoader ConfigLoader, logOut io.Writer) (BaseDeps, error)
 	}
 
 	// TODO: use logging.Config in RuntimeConfig instead of separate fields
-	logConf := &logging.Config{
+	logConf := logging.Config{
 		LogLevel:          cfg.LogLevel,
 		LogJSON:           cfg.LogJSON,
 		Name:              logging.Agent,
@@ -62,7 +62,7 @@ func NewBaseDeps(configLoader ConfigLoader, logOut io.Writer) (BaseDeps, error)
 		LogRotateBytes:    cfg.LogRotateBytes,
 		LogRotateMaxFiles: cfg.LogRotateMaxFiles,
 	}
-	d.Logger, err = logging.Setup(logConf, []io.Writer{logOut})
+	d.Logger, err = logging.Setup(logConf, logOut)
 	if err != nil {
 		return d, err
 	}

command/connect/proxy/proxy.go

@@ -3,7 +3,6 @@ package proxy
 import (
 	"flag"
 	"fmt"
-	"io"
 	"log"
 	"net"
 	"net/http"
@@ -132,7 +131,7 @@ func (c *cmd) Run(args []string) int {
 	}
 
 	// Setup the log outputs
-	logConfig := &logging.Config{
+	logConfig := logging.Config{
 		LogLevel: c.logLevel,
 		Name:     logging.Proxy,
 		LogJSON:  c.logJSON,
@@ -140,7 +139,7 @@ func (c *cmd) Run(args []string) int {
 
 	logGate := logging.GatedWriter{Writer: &cli.UiWriter{Ui: c.UI}}
 
-	logger, err := logging.Setup(logConfig, []io.Writer{&logGate})
+	logger, err := logging.Setup(logConfig, &logGate)
 	if err != nil {
 		c.UI.Error(err.Error())
 		return 1

logging/logger.go

@@ -52,34 +52,25 @@ var (
 
 type LogSetupErrorFn func(string)
 
-// Setup is used to perform setup of several logging objects:
+// Setup logging from Config, and return an hclog Logger.
 //
-// * A hclog.Logger is used to perform filtering by log level and write to io.Writer.
+// Logs may be written to out, and optionally to syslog, and a file.
-// * A GatedWriter is used to buffer logs until startup UI operations are
+func Setup(config Config, out io.Writer) (hclog.InterceptLogger, error) {
-//   complete. After this is flushed then logs flow directly to output
-//   destinations.
-// * An io.Writer is provided as the sink for all logs to flow to.
-//
-// The provided ui object will get any log messages related to setting up
-// logging itself, and will also be hooked up to the gated logger. The final bool
-// parameter indicates if logging was set up successfully.
-// TODO: accept a single io.Writer
-func Setup(config *Config, writers []io.Writer) (hclog.InterceptLogger, error) {
 	if !ValidateLogLevel(config.LogLevel) {
 		return nil, fmt.Errorf("Invalid log level: %s. Valid log levels are: %v",
 			config.LogLevel,
 			allowedLogLevels)
 	}
 
-	// Set up syslog if it's enabled.
+	writers := []io.Writer{out}
-	var syslog io.Writer
+
 	if config.EnableSyslog {
 		retries := 12
 		delay := 5 * time.Second
 		for i := 0; i <= retries; i++ {
-			l, err := gsyslog.NewLogger(gsyslog.LOG_NOTICE, config.SyslogFacility, "consul")
+			syslog, err := gsyslog.NewLogger(gsyslog.LOG_NOTICE, config.SyslogFacility, "consul")
 			if err == nil {
-				syslog = &SyslogWrapper{l}
+				writers = append(writers, syslog)
 				break
 			}
 
@@ -92,10 +83,6 @@ func Setup(config *Config, writers []io.Writer) (hclog.InterceptLogger, error) {
 		}
 	}
 
-	if syslog != nil {
-		writers = append(writers, syslog)
-	}
-
 	// Create a file logger if the user has specified the path to the log file
 	if config.LogFilePath != "" {
 		dir, fileName := filepath.Split(config.LogFilePath)

logging/logger_test.go

@@ -4,7 +4,6 @@ import (
 	"bytes"
 	"encoding/json"
 	"errors"
-	"io"
 	"os"
 	"testing"
 
@@ -15,9 +14,7 @@ import (
 func TestLogger_SetupBasic(t *testing.T) {
 	t.Parallel()
 	require := require.New(t)
-	cfg := &Config{
+	cfg := Config{LogLevel: "INFO"}
-		LogLevel: "INFO",
-	}
 
 	logger, err := Setup(cfg, nil)
 	require.NoError(err)
@@ -26,7 +23,7 @@ func TestLogger_SetupBasic(t *testing.T) {
 
 func TestLogger_SetupInvalidLogLevel(t *testing.T) {
 	t.Parallel()
-	cfg := &Config{}
+	cfg := Config{}
 
 	_, err := Setup(cfg, nil)
 	testutil.RequireErrorContains(t, err, "Invalid log level")
@@ -61,7 +58,7 @@ func TestLogger_SetupLoggerErrorLevel(t *testing.T) {
 			require := require.New(t)
 			var buf bytes.Buffer
 
-			logger, err := Setup(&cfg, []io.Writer{&buf})
+			logger, err := Setup(cfg, &buf)
 			require.NoError(err)
 			require.NotNil(logger)
 
@@ -79,12 +76,10 @@ func TestLogger_SetupLoggerErrorLevel(t *testing.T) {
 func TestLogger_SetupLoggerDebugLevel(t *testing.T) {
 	t.Parallel()
 	require := require.New(t)
-	cfg := &Config{
+	cfg := Config{LogLevel: "DEBUG"}
-		LogLevel: "DEBUG",
-	}
 	var buf bytes.Buffer
 
-	logger, err := Setup(cfg, []io.Writer{&buf})
+	logger, err := Setup(cfg, &buf)
 	require.NoError(err)
 	require.NotNil(logger)
 
@@ -100,13 +95,13 @@ func TestLogger_SetupLoggerDebugLevel(t *testing.T) {
 func TestLogger_SetupLoggerWithName(t *testing.T) {
 	t.Parallel()
 	require := require.New(t)
-	cfg := &Config{
+	cfg := Config{
 		LogLevel: "DEBUG",
 		Name:     "test-system",
 	}
 	var buf bytes.Buffer
 
-	logger, err := Setup(cfg, []io.Writer{&buf})
+	logger, err := Setup(cfg, &buf)
 	require.NoError(err)
 	require.NotNil(logger)
 
@@ -118,14 +113,14 @@ func TestLogger_SetupLoggerWithName(t *testing.T) {
 func TestLogger_SetupLoggerWithJSON(t *testing.T) {
 	t.Parallel()
 	require := require.New(t)
-	cfg := &Config{
+	cfg := Config{
 		LogLevel: "DEBUG",
 		LogJSON:  true,
 		Name:     "test-system",
 	}
 	var buf bytes.Buffer
 
-	logger, err := Setup(cfg, []io.Writer{&buf})
+	logger, err := Setup(cfg, &buf)
 	require.NoError(err)
 	require.NotNil(logger)
 
@@ -146,13 +141,13 @@ func TestLogger_SetupLoggerWithValidLogPath(t *testing.T) {
 
 	tmpDir := testutil.TempDir(t, t.Name())
 
-	cfg := &Config{
+	cfg := Config{
 		LogLevel:    "INFO",
 		LogFilePath: tmpDir + "/",
 	}
 	var buf bytes.Buffer
 
-	logger, err := Setup(cfg, []io.Writer{&buf})
+	logger, err := Setup(cfg, &buf)
 	require.NoError(err)
 	require.NotNil(logger)
 }
@@ -161,13 +156,13 @@ func TestLogger_SetupLoggerWithInValidLogPath(t *testing.T) {
 	t.Parallel()
 	require := require.New(t)
 
-	cfg := &Config{
+	cfg := Config{
 		LogLevel:    "INFO",
 		LogFilePath: "nonexistentdir/",
 	}
 	var buf bytes.Buffer
 
-	logger, err := Setup(cfg, []io.Writer{&buf})
+	logger, err := Setup(cfg, &buf)
 	require.Error(err)
 	require.True(errors.Is(err, os.ErrNotExist))
 	require.Nil(logger)
@@ -182,13 +177,13 @@ func TestLogger_SetupLoggerWithInValidLogPathPermission(t *testing.T) {
 	os.Mkdir(tmpDir, 0000)
 	defer os.RemoveAll(tmpDir)
 
-	cfg := &Config{
+	cfg := Config{
 		LogLevel:    "INFO",
 		LogFilePath: tmpDir + "/",
 	}
 	var buf bytes.Buffer
 
-	logger, err := Setup(cfg, []io.Writer{&buf})
+	logger, err := Setup(cfg, &buf)
 	require.Error(err)
 	require.True(errors.Is(err, os.ErrPermission))
 	require.Nil(logger)