Configure workers to log to a file (#59)

* Configure workers to log to a file As a best practice. Inspired by https://github.com/uber-go/zap/blob/845ca51d5b8d9fed9fe14f35ab13b6b160d5762d/FAQ.md#does-zap-support-log-rotation * Removed redundant error check * Make log file optional
cirruslabs · Mar 24, 2023 · f420268 · f420268
1 parent 67702ed
commit f420268
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Showing 3 changed files with 27 additions and 1 deletion.
diff --git a/go.mod b/go.mod
@@ -69,5 +69,6 @@ require (
 	golang.org/x/sys v0.5.0 // indirect
 	golang.org/x/text v0.7.0 // indirect
 	google.golang.org/genproto v0.0.0-20230110181048-76db0878b65f // indirect
+	gopkg.in/natefinch/lumberjack.v2 v2.2.1 // indirect
 	gopkg.in/yaml.v2 v2.4.0 // indirect
 )
diff --git a/go.sum b/go.sum
@@ -294,6 +294,8 @@ gopkg.in/check.v1 v1.0.0-20190902080502-41f04d3bba15/go.mod h1:Co6ibVJAznAaIkqp8
 gopkg.in/check.v1 v1.0.0-20201130134442-10cb98267c6c h1:Hei/4ADfdWqJk1ZMxUNpqntNwaWcugrBjAiHlqqRiVk=
 gopkg.in/check.v1 v1.0.0-20201130134442-10cb98267c6c/go.mod h1:JHkPIbrfpd72SG/EVd6muEfDQjcINNoR0C8j2r3qZ4Q=
 gopkg.in/errgo.v2 v2.1.0/go.mod h1:hNsd1EY+bozCKY1Ytp96fpM3vjJbqLJn88ws8XvfDNI=
+gopkg.in/natefinch/lumberjack.v2 v2.2.1 h1:bBRl1b0OH9s/DuPhuXpNl+VtCaJXFZ5/uEFST95x9zc=
+gopkg.in/natefinch/lumberjack.v2 v2.2.1/go.mod h1:YD8tP3GAjkrDg1eZH7EGmyESg/lsYskCTPBJVb9jqSc=
 gopkg.in/yaml.v1 v1.0.0-20140924161607-9f9df34309c0/go.mod h1:WDnlLJ4WF5VGsH/HVa3CI79GS0ol3YnhVnKP89i0kNg=
 gopkg.in/yaml.v2 v2.2.2/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
 gopkg.in/yaml.v2 v2.4.0 h1:D8xgwECY7CYvx+Y2n4sBz93Jn9JRvxdiyyo8CTfuKaY=

diff --git a/internal/command/worker/run.go b/internal/command/worker/run.go
@@ -8,11 +8,14 @@ import (
 	"github.com/cirruslabs/orchard/pkg/client"
 	"github.com/spf13/cobra"
 	"go.uber.org/zap"
+	"go.uber.org/zap/zapcore"
+	"gopkg.in/natefinch/lumberjack.v2"
 )
 
 var ErrBootstrapTokenNotProvided = errors.New("no bootstrap token provided")
 
 var bootstrapTokenRaw string
+var logFilePath string
 
 func newRunCommand() *cobra.Command {
 	cmd := &cobra.Command{
@@ -23,6 +26,8 @@ func newRunCommand() *cobra.Command {
 	}
 	cmd.PersistentFlags().StringVar(&bootstrapTokenRaw, "bootstrap-token", "",
 		"a bootstrap token retrieved via `orchard get bootstrap-token <service-account-name-for-workers>`")
+	cmd.PersistentFlags().StringVar(&logFilePath, "log-file", "",
+		"optional path to a file where logs (up to 100 Mb) will be written.")
 	return cmd
 }
 
@@ -49,10 +54,11 @@ func runWorker(cmd *cobra.Command, args []string) (err error) {
 	}
 
 	// Initialize the logger
-	logger, err := zap.NewProduction()
+	logger, err := createLogger()
 	if err != nil {
 		return err
 	}
+
 	defer func() {
 		if syncErr := logger.Sync(); syncErr != nil && err == nil {
 			err = syncErr
@@ -66,3 +72,20 @@ func runWorker(cmd *cobra.Command, args []string) (err error) {
 
 	return workerInstance.Run(cmd.Context())
 }
+
+func createLogger() (*zap.Logger, error) {
+	if logFilePath == "" {
+		return zap.NewProduction()
+	}
+
+	logFileWriter := zapcore.AddSync(&lumberjack.Logger{
+		Filename: logFilePath,
+		MaxSize:  100, // megabytes
+	})
+	core := zapcore.NewCore(
+		zapcore.NewJSONEncoder(zap.NewProductionEncoderConfig()),
+		logFileWriter,
+		zap.InfoLevel,
+	)
+	return zap.New(core), nil
+}