feat: support writing audit events to stdout for log

Signed-off-by: Mark Phelps <[email protected]>

internal/cmd/grpc.go

@@ -26,7 +26,7 @@ import (
 	"go.flipt.io/flipt/internal/server/analytics/clickhouse"
 	"go.flipt.io/flipt/internal/server/audit"
 	"go.flipt.io/flipt/internal/server/audit/cloud"
-	"go.flipt.io/flipt/internal/server/audit/logfile"
+	"go.flipt.io/flipt/internal/server/audit/log"
 	"go.flipt.io/flipt/internal/server/audit/template"
 	"go.flipt.io/flipt/internal/server/audit/webhook"
 	authmiddlewaregrpc "go.flipt.io/flipt/internal/server/authn/middleware/grpc"
@@ -350,10 +350,10 @@ func NewGRPCServer(
 	// audit sinks configuration
 	sinks := make([]audit.Sink, 0)
 
-	if cfg.Audit.Sinks.LogFile.Enabled {
-		logFileSink, err := logfile.NewSink(logger, cfg.Audit.Sinks.LogFile.File)
+	if cfg.Audit.Sinks.Log.Enabled {
+		logFileSink, err := log.NewSink(logger, cfg.Audit.Sinks.Log.File)
 		if err != nil {
-			return nil, fmt.Errorf("opening file at path: %s", cfg.Audit.Sinks.LogFile.File)
+			return nil, fmt.Errorf("opening file at path: %s", cfg.Audit.Sinks.Log.File)
 		}
 
 		sinks = append(sinks, logFileSink)

internal/config/audit.go

@@ -20,7 +20,7 @@ type AuditConfig struct {
 
 // Enabled returns true if any nested sink is enabled
 func (c AuditConfig) Enabled() bool {
-	return c.Sinks.LogFile.Enabled || c.Sinks.Webhook.Enabled || c.Sinks.Cloud.Enabled
+	return c.Sinks.Log.Enabled || c.Sinks.Webhook.Enabled || c.Sinks.Cloud.Enabled
 }
 
 func (c AuditConfig) IsZero() bool {
@@ -52,10 +52,6 @@ func (c *AuditConfig) setDefaults(v *viper.Viper) error {
 }
 
 func (c *AuditConfig) validate() error {
-	if c.Sinks.LogFile.Enabled && c.Sinks.LogFile.File == "" {
-		return errors.New("file not specified")
-	}
-
 	if c.Sinks.Webhook.Enabled {
 		if c.Sinks.Webhook.URL == "" && len(c.Sinks.Webhook.Templates) == 0 {
 			return errors.New("url or template(s) not provided")
@@ -80,7 +76,7 @@ func (c *AuditConfig) validate() error {
 // SinksConfig contains configuration held in structures for the different sinks
 // that we will send audits to.
 type SinksConfig struct {
-	LogFile LogFileSinkConfig `json:"log,omitempty" mapstructure:"log" yaml:"log,omitempty"`
+	Log     LogSinkConfig     `json:"log,omitempty" mapstructure:"log" yaml:"log,omitempty"`
 	Webhook WebhookSinkConfig `json:"webhook,omitempty" mapstructure:"webhook" yaml:"webhook,omitempty"`
 	Cloud   CloudSinkConfig   `json:"cloud,omitempty" mapstructure:"cloud" yaml:"cloud,omitempty"`
 }
@@ -99,9 +95,9 @@ type WebhookSinkConfig struct {
 	Templates          []WebhookTemplate `json:"templates,omitempty" mapstructure:"templates" yaml:"templates,omitempty"`
 }
 
-// LogFileSinkConfig contains fields that hold configuration for sending audits
-// to a log file.
-type LogFileSinkConfig struct {
+// LogSinkConfig contains fields that hold configuration for sending audits
+// to a log.
+type LogSinkConfig struct {
 	Enabled bool   `json:"enabled,omitempty" mapstructure:"enabled" yaml:"enabled,omitempty"`
 	File    string `json:"file,omitempty" mapstructure:"file" yaml:"file,omitempty"`
 }

internal/config/config.go

@@ -607,7 +607,7 @@ func Default() *Config {
 
 		Audit: AuditConfig{
 			Sinks: SinksConfig{
-				LogFile: LogFileSinkConfig{
+				Log: LogSinkConfig{
 					Enabled: false,
 					File:    "",
 				},

internal/config/config_test.go

@@ -643,7 +643,7 @@ func TestLoad(t *testing.T) {
 
 				cfg.Audit = AuditConfig{
 					Sinks: SinksConfig{
-						LogFile: LogFileSinkConfig{
+						Log: LogSinkConfig{
 							Enabled: true,
 							File:    "/path/to/logs.txt",
 						},
@@ -827,9 +827,13 @@ func TestLoad(t *testing.T) {
 			wantErr: errors.New("flush period below 2 minutes or greater than 5 minutes"),
 		},
 		{
-			name:    "file not specified",
-			path:    "./testdata/audit/invalid_enable_without_file.yml",
-			wantErr: errors.New("file not specified"),
+			name: "file not specified",
+			path: "./testdata/audit/enable_without_file.yml",
+			expected: func() *Config {
+				cfg := Default()
+				cfg.Audit.Sinks.Log.Enabled = true
+				return cfg
+			},
 		},
 		{
 			name:    "url or template not specified",

internal/server/audit/logfile/logfile.go → internal/server/audit/log/log.go

@@ -1,4 +1,4 @@
-package logfile
+package log
 
 import (
 	"context"
@@ -42,12 +42,12 @@ func (osFS) MkdirAll(path string, perm os.FileMode) error {
 	return os.MkdirAll(path, perm)
 }
 
-const sinkType = "logfile"
+const sinkType = "log"
 
-// Sink is the structure in charge of sending Audits to a specified file location.
+// Sink is the structure in charge of sending audit events to a specified file location.
 type Sink struct {
 	logger *zap.Logger
-	file   file
+	f      file
 	mtx    sync.Mutex
 	enc    *json.Encoder
 }
@@ -59,26 +59,33 @@ func NewSink(logger *zap.Logger, path string) (audit.Sink, error) {
 
 // newSink is the constructor for a Sink visible for testing.
 func newSink(logger *zap.Logger, path string, fs filesystem) (audit.Sink, error) {
-	// check if path exists, if not create it
-	dir := filepath.Dir(path)
-	if _, err := fs.Stat(dir); err != nil {
-		if !os.IsNotExist(err) {
-			return nil, fmt.Errorf("checking log directory: %w", err)
+	var f file
+
+	if path == "" {
+		f = os.Stdout
+	} else {
+		// check if path exists, if not create it
+		dir := filepath.Dir(path)
+		if _, err := fs.Stat(dir); err != nil {
+			if !os.IsNotExist(err) {
+				return nil, fmt.Errorf("checking log directory: %w", err)
+			}
+
+			if err := fs.MkdirAll(dir, 0755); err != nil {
+				return nil, fmt.Errorf("creating log directory: %w", err)
+			}
 		}
 
-		if err := fs.MkdirAll(dir, 0755); err != nil {
-			return nil, fmt.Errorf("creating log directory: %w", err)
+		var err error
+		f, err = fs.OpenFile(path, os.O_WRONLY|os.O_APPEND|os.O_CREATE, 0666)
+		if err != nil {
+			return nil, fmt.Errorf("opening log file: %w", err)
 		}
 	}
 
-	f, err := fs.OpenFile(path, os.O_WRONLY|os.O_APPEND|os.O_CREATE, 0666)
-	if err != nil {
-		return nil, fmt.Errorf("opening log file: %w", err)
-	}
-
 	return &Sink{
 		logger: logger,
-		file:   f,
+		f:      f,
 		enc:    json.NewEncoder(f),
 	}, nil
 }
@@ -91,7 +98,7 @@ func (l *Sink) SendAudits(ctx context.Context, events []audit.Event) error {
 	for _, e := range events {
 		err := l.enc.Encode(e)
 		if err != nil {
-			l.logger.Error("failed to write audit event to file", zap.String("file", l.file.Name()), zap.Error(err))
+			l.logger.Error("failed to write audit event", zap.String("file", l.f.Name()), zap.Error(err))
 			result = multierror.Append(result, err)
 		}
 	}
@@ -102,7 +109,7 @@ func (l *Sink) SendAudits(ctx context.Context, events []audit.Event) error {
 func (l *Sink) Close() error {
 	l.mtx.Lock()
 	defer l.mtx.Unlock()
-	return l.file.Close()
+	return l.f.Close()
 }
 
 func (l *Sink) String() string {

internal/server/audit/logfile/logfile_test.go → internal/server/audit/log/log_test.go

@@ -1,4 +1,4 @@
-package logfile
+package log
 
 import (
 	"bytes"
@@ -29,7 +29,7 @@ func TestNewSink_NewFile(t *testing.T) {
 	require.NoError(t, err)
 
 	require.NotNil(t, sink)
-	assert.Equal(t, "logfile", sink.String())
+	assert.Equal(t, "log", sink.String())
 
 	require.NoError(t, sink.Close())
 }
@@ -51,7 +51,7 @@ func TestNewSink_ExistingFile(t *testing.T) {
 	require.NoError(t, err)
 
 	require.NotNil(t, sink)
-	assert.Equal(t, "logfile", sink.String())
+	assert.Equal(t, "log", sink.String())
 
 	require.NoError(t, sink.Close())
 }
@@ -86,7 +86,7 @@ func TestNewSink_DirNotExists(t *testing.T) {
 			require.NoError(t, err)
 
 			require.NotNil(t, sink)
-			assert.Equal(t, "logfile", sink.String())
+			assert.Equal(t, "log", sink.String())
 
 			require.NoError(t, sink.Close())
 		})

internal/telemetry/telemetry.go

@@ -238,7 +238,7 @@ func (r *Reporter) ping(_ context.Context, f file) error {
 	auditSinks := []string{}
 
 	if r.cfg.Audit.Enabled() {
-		if r.cfg.Audit.Sinks.LogFile.Enabled {
+		if r.cfg.Audit.Sinks.Log.Enabled {
 			auditSinks = append(auditSinks, "log")
 		}
 		if r.cfg.Audit.Sinks.Webhook.Enabled {

internal/telemetry/telemetry_test.go

@@ -253,7 +253,7 @@ func TestPing(t *testing.T) {
 				},
 				Audit: config.AuditConfig{
 					Sinks: config.SinksConfig{
-						LogFile: config.LogFileSinkConfig{
+						Log: config.LogSinkConfig{
 							Enabled: false,
 						},
 					},
@@ -277,7 +277,7 @@ func TestPing(t *testing.T) {
 				},
 				Audit: config.AuditConfig{
 					Sinks: config.SinksConfig{
-						LogFile: config.LogFileSinkConfig{
+						Log: config.LogSinkConfig{
 							Enabled: true,
 						},
 					},
@@ -359,7 +359,7 @@ func TestPing(t *testing.T) {
 				},
 				Audit: config.AuditConfig{
 					Sinks: config.SinksConfig{
-						LogFile: config.LogFileSinkConfig{
+						Log: config.LogSinkConfig{
 							Enabled: true,
 						},
 						Webhook: config.WebhookSinkConfig{