[MM-19315] Replace old Logger with mlog.Logger (mattermost package) (#130)

* Updated logging in Android and Apple notification servers

Refactored the logging system in both Android and Apple notification servers. Replaced `logger.Infof` with `logger.Info` for a more structured logging approach, using `mlog.String`, `mlog.Int`, and `mlog.Err` to provide additional context. This change enhances readability and allows for better log analysis.

* Refactored logging for better readability

The logging statements in the server and notification files have been refactored to improve readability. The changes include replacing `logger.Errorf` with `logger.Error` and using structured logging fields instead of string formatting. This makes it easier to understand the log messages and their associated data.

* Updated server error handling

Switched from using Panic to Fatal in the server's error handling mechanism. This change ensures that any serious errors will cause the program to exit immediately, rather than just panicking and potentially leaving the server in an unstable state.

* Updated logger type in server modules

The logger type has been updated from *Logger to *mlog.Logger in the AndroidNotificationServer, AppleNotificationServer, and Server structures. This change also affects the NewAndroidNotificationServer, NewAppleNotificationServer functions where the logger parameter type is updated accordingly.

* Updated push proxy configuration

Refactored the ConfigPushProxy struct. Deprecated LogFileLocation, EnableConsoleLog, and EnableFileLog for backward compatibility. Introduced LoggingCfgFile and LoggingCfgJSON as replacements. No changes to other existing fields.

* Refactor config loading in push proxy

Removed the automatic enabling of console log when both console and file logs are disabled. Also, removed the creation and handling of log files within the configuration loading function. This simplifies the function by focusing it solely on loading configurations.

* Enhanced logger initialization and configuration

The main function has been updated to include a more robust logger initialization process. This includes error handling for the creation of a new logger, as well as its configuration. If no logging is defined, a default config (console output) is used. A separate function has been added to provide this default logging configuration. The server now also ensures that the logger is properly shut down when it's no longer needed.

* Updated Go version and dependencies

Upgraded the Go version from 1.21 to 1.22 and updated various dependencies to their latest versions. This includes updates to firebase, gorilla handlers, mux, prometheus client_golang, common, golang.org/x/net and oauth2 among others. Also added new dependencies such as github.com/mattermost/mattermost/server/public and github.com/francoispqt/gojay.

* Refactored logging configuration setup

The default logging configuration has been refactored to support both console and file logging. The logic for generating the default config has been moved from main.go to a new file, server/logging.go. This change allows the application to dynamically choose between console or file logging based on the 'EnableFileLog' flag in the configuration.

* Revert "Updated Go version and dependencies"

This reverts commit 8e38a57.

* Updated Go version and dependencies

Upgraded the Go version from 1.21 to 1.22 and updated various dependencies to their latest versions. Also, added new dependencies required for the project's functionality.

* Update Docker image versions

The Docker images for Go and Golint have been updated to newer versions. The new version of the Go image includes various performance improvements and bug fixes. Similarly, the Golint image has also been updated to include the latest linting rules and enhancements.

* Updated logger initialization in tests

The logger initialization in various test files has been updated. Instead of using the NewLogger function, we are now using mlog.NewLogger(). This change affects android_notification_test.go, metrics_test.go, and server_test.go.

* Improved error handling and logging configuration

- Added error checks after initializing new loggers in various test functions to ensure no silent failures.
- Simplified the condition check for enabling file logs by directly using the boolean value.

* Added logging tests

Introduced a new set of unit tests for the server's logging functionality. These tests cover various aspects such as escaping double quotes, default console log configuration, file log configuration and overall logging configuration. Also added a helper function to generate random strings for testing purposes.

* Updated logging configuration in JSON

The logging settings have been simplified and restructured. The previous console and file log enablement flags have been removed. Instead, a new approach has been introduced where the logging configuration is now handled through a dedicated config file or directly via JSON.

* Added new logging configuration file

A new JSON configuration file for logging has been added. This includes settings for console type output, plain formatting, and color enabling. It also specifies minimum lengths for level and message, as well as the inclusion of caller information. Different log levels from debug to panic have been defined with corresponding IDs and optional color or stacktrace attributes.

* Refactored logger initialization and configuration

The logger initialization and configuration process has been refactored for better code organization. The logic previously in the main function is now encapsulated within a new function, NewMlogLogger, in the server package. This change also includes updates to logging tests to accommodate the new structure.

* Updated Push Proxy to version 5.9.0

This update includes several significant changes:
- The release is compatible with all versions of Mattermost server and mobile.
- Notably, Google Cloud Messaging (GCM) service has been deprecated as of April 10, 2018, and will be removed by April 11, 2019. Migration to Firebase Cloud Messaging (FCM) is necessary.
- The old Logger system has been replaced with a new one.
- Deprecated types EnableConsoleLog, EnableFileLog, and LogFileLocation from the config have been replaced.
- Lastly, we've switched from go version 1.21 to go version 1.22 for improved performance and stability.

* Updated README with CHANGELOG reference

The README file has been updated to include a reference to the CHANGELOG. This will provide users with more detailed information about the changes made in each release.

* Update server/logging.go test logic

Co-authored-by: Daniel Espino García <[email protected]>

* Refactor logging configuration logic

The logging configuration logic has been refactored for better readability. The changes mainly involve reformatting the conditionals that determine whether to use console or file log configurations.

* Refactored logging tests for better readability

The logging tests have been refactored to improve readability and maintainability. The changes include:
- Grouping related assertions into subtests using t.Run
- Using require instead of assert where appropriate to stop test execution after a failure
- Simplifying variable declarations by using the new keyword

* Updated dependencies in go.mod and go.sum

Several new dependencies have been added to the project's go.mod and go.sum files. This includes libraries for handling semantic versioning, color output, OpenGraph protocol, LDAP support, and more. These additions will provide necessary functionality for upcoming features and improvements.

* Refactor logging tests and remove random string generation

The logging test functions have been refactored for clarity, removing the 'OK' suffix from their names. The random string generation function has been removed and replaced with model.NewId() for filename creation in file log configuration tests. This change simplifies the codebase and improves readability of the test cases.

* Refactor logging configuration

The logging configuration has been refactored to simplify the process. Deprecated fields have been removed from the ConfigPushProxy struct and replaced with a single LogFormat field. The NewMlogLogger function now uses this new field to determine the log format, defaulting to "plain" if an invalid value is provided. Additionally, helper functions have been created to build the logger configuration for both console and file outputs based on these changes. Corresponding tests have also been updated accordingly.

* Removed logging config file and updated logging settings

The logging configuration file has been removed. Logging settings have been directly integrated into the main configuration file. This includes disabling console and file logs by default, specifying log format, and removing specific log level definitions.

* Revert "Updated README with CHANGELOG reference"

This reverts commit 02a6b10.

* Revert "Updated Push Proxy to version 5.9.0"

This reverts commit 4af221e.

* Enabled console logging

The configuration has been updated to enable console logging. This change will allow for better tracking and debugging of the application's activities.

* Updated golangci-lint version in Docker image

The version of golangci-lint used in the Docker image has been downgraded. This was done to ensure compatibility with other components and improve overall stability.

* Removed logging functionality

The logging functionality and its associated tests have been removed from the server. This includes the deletion of functions for creating new loggers, building log configurations, and configuring console and file logs. The changes aim to simplify the codebase by eliminating unnecessary components.

* Refactored import statements in multiple files

The import statements for the 'mlog' package and a few others have been restructured across several server files. This change improves readability and consistency of the codebase.

* Refactored logging system

The existing logging system has been replaced with a more flexible one. The new logger is based on the mlog library, which allows for different log formats and configurable targets. This change also includes updates to the logger configuration process and removes some helper methods that were previously used in the application. Tests have been updated accordingly to reflect these changes.

* Updated logging messages for notifications

The logging messages in the Android and Apple notification servers have been updated to improve clarity. The changes include:
- Removed specific identifiers from the log messages when sending push notifications.
- Standardized the naming convention of 'ack_id' across all logs.
- Simplified log message when initializing apple notification server with AuthKey.
- Updated acknowledgment delivery receipt log message for better readability.

* Enhanced logging and timeout configuration

Added logic to ensure at least one type of logging (console or file) is enabled. If both are disabled, console logging will be turned on by default. For file logging, if the log file location is not specified, it will create a new directory for logs and set the log file location there. If the directory creation fails, it logs in the current directory itself. Also ensured that if the log file does not exist, it gets created. Additionally, refined timeout settings by setting defaults if they're not provided in the configuration.

* Refactor logger initialization

Simplified the logger initialization process by removing unnecessary comments and renaming the function used to create a new logger. This change makes the code cleaner and easier to read.

* fix more issues

* Empty commit

* Revert "Empty commit"

This reverts commit e35b0d6.

* Trigger CI

---------

Co-authored-by: Daniel Espino García <[email protected]>
Co-authored-by: Agniva De Sarker <[email protected]>

Author: 3 people

Makefile

@@ -64,7 +64,7 @@ ifneq ($(shell echo $(APP_VERSION) | egrep '^v([0-9]+\.){0,2}(\*|[0-9]+)'),)
 endif
 
 ## Docker Images
-DOCKER_IMAGE_GO         ?= "golang:${GO_VERSION}@sha256:d83472f1ab5712a6b2b816dc811e46155e844ddc02f5f5952e72c6deedafed77"
+DOCKER_IMAGE_GO         ?= "golang:${GO_VERSION}@sha256:21edeab9ed48e9820f0b447cce6ce1900b3aa90ffce3c8b4de7fae5ac333de0c"
 DOCKER_IMAGE_GOLINT     ?= "golangci/golangci-lint:v1.57.2@sha256:8f3a60a00a83bb7d599d2e028ac0c3573dc2b9ec0842590f1c2e59781c821da7"
 DOCKER_IMAGE_DOCKERLINT ?= "hadolint/hadolint:v2.12.0"
 DOCKER_IMAGE_COSIGN     ?= "bitnami/cosign:1.8.0@sha256:8c2c61c546258fffff18b47bb82a65af6142007306b737129a7bd5429d53629a"

config/mattermost-push-proxy.sample.json

@@ -40,5 +40,6 @@
     ],
     "EnableConsoleLog": true,
     "EnableFileLog": false,
-    "LogFileLocation": ""
+    "LogFileLocation": "",
+    "LogFormat": "plain"
 }

go.mod

@@ -1,22 +1,22 @@
 module github.com/mattermost/mattermost-push-proxy
 
-go 1.21
+go 1.22
 
-toolchain go1.21.9
+toolchain go1.22.10
 
 require (
 	firebase.google.com/go/v4 v4.14.0
 	github.com/gorilla/handlers v1.5.2
 	github.com/gorilla/mux v1.8.1
 	github.com/kyokomi/emoji v2.2.4+incompatible
+	github.com/mattermost/mattermost/server/public v0.1.9
 	github.com/prometheus/client_golang v1.19.0
 	github.com/prometheus/common v0.53.0
 	github.com/sideshow/apns2 v0.23.0
 	github.com/stretchr/testify v1.9.0
-	golang.org/x/net v0.24.0
-	golang.org/x/oauth2 v0.19.0
+	golang.org/x/net v0.27.0
+	golang.org/x/oauth2 v0.21.0
 	google.golang.org/api v0.176.1
-	gopkg.in/natefinch/lumberjack.v2 v2.2.1
 	gopkg.in/throttled/throttled.v1 v1.0.0
 )
 
@@ -33,8 +33,9 @@ require (
 	github.com/PuerkitoBio/boom v0.0.0-20140219125548-fecdef1c97ca // indirect
 	github.com/beorn7/perks v1.0.1 // indirect
 	github.com/cespare/xxhash/v2 v2.3.0 // indirect
-	github.com/davecgh/go-spew v1.1.1 // indirect
+	github.com/davecgh/go-spew v1.1.2-0.20180830191138-d8f796af33cc // indirect
 	github.com/felixge/httpsnoop v1.0.4 // indirect
+	github.com/francoispqt/gojay v1.2.13 // indirect
 	github.com/garyburd/redigo v1.6.4 // indirect
 	github.com/go-logr/logr v1.4.1 // indirect
 	github.com/go-logr/stdr v1.2.2 // indirect
@@ -46,28 +47,33 @@ require (
 	github.com/googleapis/enterprise-certificate-proxy v0.3.2 // indirect
 	github.com/googleapis/gax-go/v2 v2.12.3 // indirect
 	github.com/kr/text v0.2.0 // indirect
+	github.com/mattermost/logr/v2 v2.0.21 // indirect
 	github.com/olekukonko/ts v0.0.0-20171002115256-78ecb04241c0 // indirect
-	github.com/pmezard/go-difflib v1.0.0 // indirect
+	github.com/pkg/errors v0.9.1 // indirect
+	github.com/pmezard/go-difflib v1.0.1-0.20181226105442-5d4384ee4fb2 // indirect
 	github.com/prometheus/client_model v0.6.1 // indirect
 	github.com/prometheus/procfs v0.14.0 // indirect
 	github.com/rakyll/pb v0.0.0-20160123035540-8d46b8b097ef // indirect
 	github.com/rogpeppe/go-internal v1.11.0 // indirect
+	github.com/wiggin77/merror v1.0.5 // indirect
+	github.com/wiggin77/srslog v1.0.1 // indirect
 	go.opencensus.io v0.24.0 // indirect
 	go.opentelemetry.io/contrib/instrumentation/google.golang.org/grpc/otelgrpc v0.51.0 // indirect
 	go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp v0.51.0 // indirect
 	go.opentelemetry.io/otel v1.26.0 // indirect
 	go.opentelemetry.io/otel/metric v1.26.0 // indirect
 	go.opentelemetry.io/otel/trace v1.26.0 // indirect
-	golang.org/x/crypto v0.22.0 // indirect
+	golang.org/x/crypto v0.25.0 // indirect
 	golang.org/x/sync v0.7.0 // indirect
-	golang.org/x/sys v0.19.0 // indirect
-	golang.org/x/text v0.14.0 // indirect
+	golang.org/x/sys v0.22.0 // indirect
+	golang.org/x/text v0.16.0 // indirect
 	golang.org/x/time v0.5.0 // indirect
 	google.golang.org/appengine/v2 v2.0.6 // indirect
 	google.golang.org/genproto v0.0.0-20240415180920-8c6c420018be // indirect
-	google.golang.org/genproto/googleapis/api v0.0.0-20240415180920-8c6c420018be // indirect
-	google.golang.org/genproto/googleapis/rpc v0.0.0-20240415180920-8c6c420018be // indirect
-	google.golang.org/grpc v1.63.2 // indirect
-	google.golang.org/protobuf v1.33.0 // indirect
+	google.golang.org/genproto/googleapis/api v0.0.0-20240528184218-531527333157 // indirect
+	google.golang.org/genproto/googleapis/rpc v0.0.0-20240722135656-d784300faade // indirect
+	google.golang.org/grpc v1.65.0 // indirect
+	google.golang.org/protobuf v1.34.2 // indirect
+	gopkg.in/natefinch/lumberjack.v2 v2.2.1 // indirect
 	gopkg.in/yaml.v3 v3.0.1 // indirect
 )

go.sum

@@ -39,7 +39,16 @@ func main() {
 		log.Fatal(err)
 	}
 
-	logger := server.NewLogger(cfg)
+	logger, err := server.NewLogger(cfg)
+	defer func() {
+		if logger != nil {
+			_ = logger.Shutdown()
+		}
+	}()
+	if err != nil {
+		log.Fatal(err)
+	}
+
 	logger.Info("Loading " + fileName)
 
 	srv := server.New(cfg, logger)

main.go

@@ -18,6 +18,8 @@ import (
 	"github.com/kyokomi/emoji"
 	"golang.org/x/oauth2/google"
 	"google.golang.org/api/option"
+
+	"github.com/mattermost/mattermost/server/public/shared/mlog"
 )
 
 const (
@@ -37,7 +39,7 @@ const (
 
 type AndroidNotificationServer struct {
 	metrics             *metrics
-	logger              *Logger
+	logger              *mlog.Logger
 	AndroidPushSettings AndroidPushSettings
 	client              *messaging.Client
 	sendTimeout         time.Duration
@@ -54,7 +56,7 @@ type serviceAccount struct {
 	TokenURI    string `json:"token_uri"`
 }
 
-func NewAndroidNotificationServer(settings AndroidPushSettings, logger *Logger, metrics *metrics, sendTimeoutSecs int) *AndroidNotificationServer {
+func NewAndroidNotificationServer(settings AndroidPushSettings, logger *mlog.Logger, metrics *metrics, sendTimeoutSecs int) *AndroidNotificationServer {
 	return &AndroidNotificationServer{
 		AndroidPushSettings: settings,
 		metrics:             metrics,
@@ -64,10 +66,10 @@ func NewAndroidNotificationServer(settings AndroidPushSettings, logger *Logger,
 }
 
 func (me *AndroidNotificationServer) Initialize() error {
-	me.logger.Infof("Initializing Android notification server for type=%v", me.AndroidPushSettings.Type)
+	me.logger.Info("Initializing Android notification server", mlog.String("type", me.AndroidPushSettings.Type))
 
 	if me.AndroidPushSettings.AndroidAPIKey != "" {
-		me.logger.Infof("AndroidPushSettings.AndroidAPIKey is no longer used. Please remove this config value.")
+		me.logger.Info("AndroidPushSettings.AndroidAPIKey is no longer used. Please remove this config value.")
 	}
 
 	if me.AndroidPushSettings.ServiceFileLocation == "" {
@@ -169,7 +171,12 @@ func (me *AndroidNotificationServer) SendNotification(msg *PushNotification) Pus
 	ctx, cancel := context.WithTimeout(context.Background(), me.sendTimeout)
 	defer cancel()
 
-	me.logger.Infof("Sending android push notification for device=%v type=%v ackId=%v", me.AndroidPushSettings.Type, msg.Type, msg.AckID)
+	me.logger.Info(
+		"Sending android push notification",
+		mlog.String("device", me.AndroidPushSettings.Type),
+		mlog.String("type", msg.Type),
+		mlog.String("ack_id", msg.AckID),
+	)
 
 	start := time.Now()
 	_, err := me.client.Send(ctx, fcmMsg)
@@ -183,17 +190,17 @@ func (me *AndroidNotificationServer) SendNotification(msg *PushNotification) Pus
 			errorCode = "NONE"
 		}
 
-		me.logger.Errorf(
-			"Failed to send FCM push sid=%v did=%v err=%v type=%v errorCode=%v",
-			msg.ServerID,
-			msg.DeviceID,
-			err,
-			me.AndroidPushSettings.Type,
-			errorCode,
+		me.logger.Error(
+			"Failed to send FCM push",
+			mlog.String("sid", msg.ServerID),
+			mlog.String("did", msg.DeviceID),
+			mlog.Err(err),
+			mlog.String("type", me.AndroidPushSettings.Type),
+			mlog.String("errorCode", errorCode),
 		)
 
 		if messaging.IsUnregistered(err) || messaging.IsSenderIDMismatch(err) {
-			me.logger.Infof("Android response failure sending remove code: type=%v", me.AndroidPushSettings.Type)
+			me.logger.Info("Android response failure sending remove code", mlog.String("type", me.AndroidPushSettings.Type))
 			if me.metrics != nil {
 				me.metrics.incrementRemoval(PushNotifyAndroid, pushType, unregistered)
 			}

server/android_notification_server.go

@@ -11,14 +11,17 @@ import (
 	"testing"
 
 	"github.com/stretchr/testify/require"
+
+	"github.com/mattermost/mattermost/server/public/shared/mlog"
 )
 
 func TestAndroidInitialize(t *testing.T) {
 	fileName := FindConfigFile("mattermost-push-proxy.sample.json")
 	cfg, err := LoadConfig(fileName)
 	require.NoError(t, err)
 
-	logger := NewLogger(cfg)
+	logger, err := mlog.NewLogger()
+	require.NoError(t, err)
 
 	// Verify error for no service file
 	pushSettings := AndroidPushSettings{}

server/android_notification_test.go

@@ -17,18 +17,20 @@ import (
 	"github.com/sideshow/apns2/payload"
 	"github.com/sideshow/apns2/token"
 	"golang.org/x/net/http2"
+
+	"github.com/mattermost/mattermost/server/public/shared/mlog"
 )
 
 type AppleNotificationServer struct {
 	AppleClient       *apns.Client
 	metrics           *metrics
-	logger            *Logger
+	logger            *mlog.Logger
 	ApplePushSettings ApplePushSettings
 	sendTimeout       time.Duration
 	retryTimeout      time.Duration
 }
 
-func NewAppleNotificationServer(settings ApplePushSettings, logger *Logger, metrics *metrics, sendTimeoutSecs int, retryTimeoutSecs int) *AppleNotificationServer {
+func NewAppleNotificationServer(settings ApplePushSettings, logger *mlog.Logger, metrics *metrics, sendTimeoutSecs int, retryTimeoutSecs int) *AppleNotificationServer {
 	return &AppleNotificationServer{
 		ApplePushSettings: settings,
 		metrics:           metrics,
@@ -64,9 +66,9 @@ func (me *AppleNotificationServer) setupProxySettings(appleCert *tls.Certificate
 	}
 
 	if appleCert != nil {
-		me.logger.Infof("Initializing apple notification server for type=%v with PEM certificate", me.ApplePushSettings.Type)
+		me.logger.Info("Initializing apple notification server with PEM certificate", mlog.String("type", me.ApplePushSettings.Type))
 	} else {
-		me.logger.Infof("Initializing apple notification server for type=%v with AuthKey", me.ApplePushSettings.Type)
+		me.logger.Info("Initializing apple notification server with AuthKey", mlog.String("type", me.ApplePushSettings.Type))
 	}
 
 	return nil
@@ -228,11 +230,22 @@ func (me *AppleNotificationServer) SendNotification(msg *PushNotification) PushR
 	}
 
 	if me.AppleClient != nil {
-		me.logger.Infof("Sending apple push notification for device=%v type=%v ackId=%v", me.ApplePushSettings.Type, msg.Type, msg.AckID)
+		me.logger.Info(
+			"Sending apple push notification",
+			mlog.String("device", me.ApplePushSettings.Type),
+			mlog.String("type", msg.Type),
+			mlog.String("ack_id", msg.AckID),
+		)
 
 		res, err := me.SendNotificationWithRetry(notification)
 		if err != nil {
-			me.logger.Errorf("Failed to send apple push sid=%v did=%v err=%v type=%v", msg.ServerID, msg.DeviceID, err, me.ApplePushSettings.Type)
+			me.logger.Error(
+				"Failed to send apple push",
+				mlog.String("sid", msg.ServerID),
+				mlog.String("did", msg.DeviceID),
+				mlog.Err(err),
+				mlog.String("type", me.ApplePushSettings.Type),
+			)
 			if me.metrics != nil {
 				me.metrics.incrementFailure(PushNotifyApple, pushType, "RequestError")
 			}
@@ -241,14 +254,26 @@ func (me *AppleNotificationServer) SendNotification(msg *PushNotification) PushR
 
 		if !res.Sent() {
 			if res.Reason == apns.ReasonBadDeviceToken || res.Reason == apns.ReasonUnregistered || res.Reason == apns.ReasonMissingDeviceToken || res.Reason == apns.ReasonDeviceTokenNotForTopic {
-				me.logger.Infof("Failed to send apple push sending remove code res ApnsID=%v reason=%v code=%v type=%v", res.ApnsID, res.Reason, res.StatusCode, me.ApplePushSettings.Type)
+				me.logger.Info(
+					"Failed to send apple push sending remove code res",
+					mlog.String("ApnsID", res.ApnsID),
+					mlog.String("reason", res.Reason),
+					mlog.Int("code", res.StatusCode),
+					mlog.String("type", me.ApplePushSettings.Type),
+				)
 				if me.metrics != nil {
 					me.metrics.incrementRemoval(PushNotifyApple, pushType, res.Reason)
 				}
 				return NewRemovePushResponse()
 			}
 
-			me.logger.Errorf("Failed to send apple push with res ApnsID=%v reason=%v code=%v type=%v", res.ApnsID, res.Reason, res.StatusCode, me.ApplePushSettings.Type)
+			me.logger.Error(
+				"Failed to send apple push with res",
+				mlog.String("ApnsID", res.ApnsID),
+				mlog.String("reason", res.Reason),
+				mlog.Int("code", res.StatusCode),
+				mlog.String("type", me.ApplePushSettings.Type),
+			)
 			if me.metrics != nil {
 				me.metrics.incrementFailure(PushNotifyApple, pushType, res.Reason)
 			}
@@ -289,10 +314,15 @@ func (me *AppleNotificationServer) SendNotificationWithRetry(notification *apns.
 			break
 		}
 
-		me.logger.Errorf("Failed to send apple push did=%v retry=%v error=%v", notification.DeviceToken, retries, err)
+		me.logger.Error(
+			"Failed to send apple push",
+			mlog.String("did", notification.DeviceToken),
+			mlog.Int("retry", retries),
+			mlog.Err(err),
+		)
 
 		if retries == MAX_RETRIES-1 {
-			me.logger.Errorf("Max retries reached did=%v", notification.DeviceToken)
+			me.logger.Error("Max retries reached", mlog.String("did", notification.DeviceToken))
 			break
 		}
 
@@ -302,7 +332,12 @@ func (me *AppleNotificationServer) SendNotificationWithRetry(notification *apns.
 		}
 
 		if generalContext.Err() != nil {
-			me.logger.Infof("Not retrying because context error did=%v retry=%v error=%v", notification.DeviceToken, retries, generalContext.Err())
+			me.logger.Info(
+				"Not retrying because context error",
+				mlog.String("did", notification.DeviceToken),
+				mlog.Int("retry", retries),
+				mlog.Err(generalContext.Err()),
+			)
 			err = generalContext.Err()
 			break
 		}

server/apple_notification_server.go

@@ -22,6 +22,7 @@ type ConfigPushProxy struct {
 	EnableMetrics           bool
 	EnableConsoleLog        bool
 	EnableFileLog           bool
+	LogFormat               string // json or plain
 	ThrottlePerSec          int
 	ThrottleMemoryStoreSize int
 }
@@ -78,7 +79,7 @@ func LoadConfig(fileName string) (*ConfigPushProxy, error) {
 		fmt.Println(buf, err)
 		return nil, err
 	}
-	// If both are disabled, that means an old config file is being used. Atleast enable console log.
+
 	if !cfg.EnableConsoleLog && !cfg.EnableFileLog {
 		cfg.EnableConsoleLog = true
 	}