Enhance logging interface

Author: everesio

Makefile

@@ -33,15 +33,23 @@ ROOT_DIR      := $(shell dirname $(realpath $(firstword $(MAKEFILE_LIST))))
 
 default: build
 
-check:
+.PHONY: help
+help:
+	@grep -E '^[a-zA-Z%_-]+:.*?## .*$$' $(MAKEFILE_LIST) | sort | awk 'BEGIN {FS = ":.*?## "}; {printf "\033[36m%-30s\033[0m %s\n", $$1, $$2}'
+
+vet: ## Go vet
 	go vet ./...
-	golint $$(go list ./...) 2>&1
+
+check: vet
 	gosec ./... 2>&1
 
-test:
+lint: ## Lint
+	golint $$(go list ./...) 2>&1
+
+test: ## Test
 	GO111MODULE=on go test -mod=vendor -v ./...
 
-build:
+build: vet ## Build executable
 	CGO_ENABLED=1 GO111MODULE=on go build -mod=vendor -o $(BINARY) $(BUILD_FLAGS) -ldflags "$(LDFLAGS)" .
 
 .PHONY: os-build
@@ -58,10 +66,10 @@ docker-push:
 	docker tag $(LOCAL_IMAGE) $(CLOUD_IMAGE)
 	docker push $(CLOUD_IMAGE)
 
-fmt:
+fmt: ## Go format
 	go fmt ./...
 
-clean:
+clean: ## Clean
 	@rm -rf $(BINARY)
 	@rm -rf $(CHART_PKG)
 
@@ -70,15 +78,15 @@ deps:
 	GO111MODULE=on go get ./...
 
 .PHONY: vendor
-vendor:
+vendor: ## Go vendor
 	GO111MODULE=on go mod vendor
 
 .PHONY: tidy
-tidy:
+tidy: ## Go tidy
 	GO111MODULE=on go mod tidy
 
 .PHONY: tag
-tag:
+tag: ## Git tag
 	git tag $(TAG)
 
 .PHONY: release-setup
@@ -97,29 +105,32 @@ release-snapshot: helm-package
 
 
 .PHONY: helm-package
-helm-package:
+helm-package: ## Package helm chart
 	$(HELM_BIN) package $(ROOT_DIR)/charts/mqtt-proxy --app-version $(TAG) --version $(CHART_VERSION) --destination $(ROOT_DIR)/$(CHART_PKG)
 	mv $(ROOT_DIR)/$(CHART_PKG)/mqtt-proxy-$(CHART_VERSION).tgz $(ROOT_DIR)/$(CHART_PKG)/mqtt-proxy-$(CHART_VERSION)-chart.tgz
 	$(HELM_BIN) repo index $(ROOT_DIR)/$(CHART_PKG) --url https://grepplabs.github.io/mqtt-proxy
 	# TODO: --merge  old_charts_dir/index.yaml
 
 .PHONY: helm-template
-helm-template:
+helm-template: ## Template helm chart
 	$(HELM_BIN) template $(SVC_NAME) $(ROOT_DIR)/charts/mqtt-proxy \
 	   -f $(ROOT_DIR)/charts/mqtt-proxy/values-$(HELM_VALUES).yaml \
 	   --namespace=$(SVC_NAMESPACE)
 
 .PHONY: helm-install
-helm-install:
+helm-install:  ## Install helm chart
 	$(HELM_BIN) upgrade $(SVC_NAME) $(ROOT_DIR)/charts/mqtt-proxy \
 	   -f $(ROOT_DIR)/charts/mqtt-proxy/values-$(HELM_VALUES).yaml \
 	   --namespace=$(SVC_NAMESPACE) \
 	   --install \
 	   --create-namespace
 
 .PHONY: helm-test
-helm-test:
+helm-test: ## Test helm chart
 	$(HELM_BIN) test $(SVC_NAME) \
 		--namespace=$(SVC_NAMESPACE)
 
 
+.PHONY: install-tools
+install-tools: ## Install tools
+	go install github.com/securego/gosec/v2/cmd/gosec@latest

README.md

@@ -25,7 +25,12 @@ MQTT Proxy allows MQTT clients to send messages to other messaging systems
     * [ ] Others
 * [x] Helm chart
 * [ ] Server certificate rotation
- 
+    * [ ] Self sign / intermediate certificates
+    * [ ] Let's Encrypt certificates
+    * [ ] HashiCorp Vault certificates
+    * [ ] K8S cert-manager
+
+
 ### Install binary release
 
 1. Download the latest Linux release

cmd/root.go

@@ -11,6 +11,7 @@ import (
 	"github.com/oklog/run"
 	"github.com/pkg/errors"
 	"github.com/prometheus/client_golang/prometheus"
+	"github.com/prometheus/client_golang/prometheus/collectors"
 	"github.com/prometheus/common/version"
 	"go.uber.org/automaxprocs/maxprocs"
 	"gopkg.in/alecthomas/kingpin.v2"
@@ -24,7 +25,7 @@ func Execute() {
 	app.Version(version.Print("mqtt-proxy"))
 	app.HelpFlag.Short('h')
 
-	logConfig := log.Configuration{}
+	logConfig := log.LogConfig{}
 	app.Flag("log.level", "Log filtering One of: [fatal, error, warn, info, debug]").Default(log.Info).EnumVar(&logConfig.LogLevel, log.Fatal, log.Error, log.Warn, log.Info, log.Debug)
 	app.Flag("log.format", "Log format to use. One of: [logfmt, json, plain]").Default(log.LogFormatLogfmt).EnumVar(&logConfig.LogFormat, log.LogFormatLogfmt, log.LogFormatJson, log.LogFormatPlain)
 	app.Flag("log.field-name.time", "Log time field name").Default(log.TimeKey).StringVar(&logConfig.LogFieldNames.Time)
@@ -45,6 +46,7 @@ func Execute() {
 	}
 
 	logger := log.NewLogger(logConfig)
+	log.InitInstance(logger)
 
 	undo, err := maxprocs.Set(maxprocs.Logger(func(template string, args ...interface{}) {
 		logger.Debugf(template, args...)
@@ -59,10 +61,11 @@ func Execute() {
 	metrics := prometheus.NewRegistry()
 	metrics.MustRegister(
 		version.NewCollector("mqtt_proxy"),
-		prometheus.NewGoCollector(),
-		prometheus.NewProcessCollector(prometheus.ProcessCollectorOpts{}),
+		collectors.NewGoCollector(
+			collectors.WithGoCollectorRuntimeMetrics(),
+		),
+		collectors.NewProcessCollector(collectors.ProcessCollectorOpts{}),
 	)
-
 	var g run.Group
 
 	if err := cmds[cmd](&g, logger, metrics); err != nil {

pkg/log/logger.go

@@ -1,5 +1,10 @@
 package log
 
+import (
+	"context"
+	"sync"
+)
+
 //Fields Type to pass when we want to call WithFields for structured logging
 type Fields map[string]interface{}
 
@@ -40,20 +45,39 @@ const (
 	LogFormatLogfmt = "logfmt"
 )
 
+const (
+	// ContextLogTag is used to identifier fields, which should be appended to a log entry, from a passed context
+	ContextLogTag string = "logging"
+)
+
 //Logger is our contract for the logger
 type Logger interface {
+	Print(message string)
+
 	Printf(format string, args ...interface{})
 
+	Debug(message string)
+
 	Debugf(format string, args ...interface{})
 
+	Info(message string)
+
 	Infof(format string, args ...interface{})
 
+	Warn(message string)
+
 	Warnf(format string, args ...interface{})
 
+	Error(message string)
+
 	Errorf(format string, args ...interface{})
 
+	Panic(message string)
+
 	Panicf(format string, args ...interface{})
 
+	Fatal(message string)
+
 	Fatalf(format string, args ...interface{})
 
 	WithFields(keyValues Fields) Logger
@@ -73,6 +97,8 @@ type Logger interface {
 	IsPanic() bool
 
 	IsFatal() bool
+
+	WithContext(context context.Context) Logger
 }
 
 type LogFieldNames struct {
@@ -83,29 +109,48 @@ type LogFieldNames struct {
 	Error   string
 }
 
-// Configuration stores the config for the logger
-type Configuration struct {
+// LogConfig stores the config for the logger
+type LogConfig struct {
 	LogFormat     string
 	LogLevel      string
 	LogFieldNames LogFieldNames
 }
 
 //NewLogger returns an instance of logger
-func NewLogger(config Configuration) Logger {
+func NewLogger(config LogConfig) Logger {
 	return newZapLogger(config)
 }
 
-var DefaultLogger = NewDefaultLogger()
+var (
+	instance Logger
+	once     sync.Once
+)
+
+//InitInstance initialize logger which will be returned by GetInstance
+func InitInstance(logger Logger) {
+	once.Do(func() {
+		instance = logger
+	})
+}
+
+func GetInstance() Logger {
+	once.Do(func() {
+		if instance == nil {
+			instance = NewDefaultLogger()
+		}
+	})
+	return instance
+}
 
 //NewDefaultLogger returns an instance of logger with default parameters
 func NewDefaultLogger() Logger {
-	config := Configuration{
+	config := LogConfig{
 		LogFormat: LogFormatLogfmt,
 		LogLevel:  Info,
 	}
 	return newZapLogger(config)
 }
 
 func Printf(format string, args ...interface{}) {
-	DefaultLogger.Printf(format, args...)
+	GetInstance().Printf(format, args...)
 }

pkg/log/zap.go

@@ -1,6 +1,7 @@
 package log
 
 import (
+	"context"
 	"os"
 
 	"github.com/sykesm/zap-logfmt"
@@ -14,7 +15,7 @@ type zapLogger struct {
 	errorKey      string
 }
 
-func getEncoder(config Configuration) zapcore.Encoder {
+func getEncoder(config LogConfig) zapcore.Encoder {
 	encoderConfig := zap.NewProductionEncoderConfig()
 	encoderConfig.EncodeTime = zapcore.ISO8601TimeEncoder
 	encoderConfig.TimeKey = getStringOrDefault(config.LogFieldNames.Time, TimeKey)
@@ -59,7 +60,7 @@ func getZapLevel(level string) zapcore.Level {
 	}
 }
 
-func newZapLogger(config Configuration) Logger {
+func newZapLogger(config LogConfig) Logger {
 	cores := []zapcore.Core{}
 
 	level := getZapLevel(config.LogLevel)
@@ -83,6 +84,10 @@ func newZapLogger(config Configuration) Logger {
 	}
 }
 
+func (l *zapLogger) Debug(message string) {
+	l.sugaredLogger.Debug(message)
+}
+
 func (l *zapLogger) Debugf(format string, args ...interface{}) {
 	l.sugaredLogger.Debugf(format, args...)
 }
@@ -95,6 +100,14 @@ func (l *zapLogger) Printf(format string, args ...interface{}) {
 	l.sugaredLogger.Infof(format, args...)
 }
 
+func (l *zapLogger) Print(message string) {
+	l.sugaredLogger.Info(message)
+}
+
+func (l *zapLogger) Info(message string) {
+	l.sugaredLogger.Info(message)
+}
+
 func (l *zapLogger) Infof(format string, args ...interface{}) {
 	l.sugaredLogger.Infof(format, args...)
 }
@@ -103,6 +116,10 @@ func (l *zapLogger) IsInfo() bool {
 	return l.level <= zapcore.InfoLevel
 }
 
+func (l *zapLogger) Warn(message string) {
+	l.sugaredLogger.Warn(message)
+}
+
 func (l *zapLogger) Warnf(format string, args ...interface{}) {
 	l.sugaredLogger.Warnf(format, args...)
 }
@@ -111,6 +128,10 @@ func (l *zapLogger) IsWarn() bool {
 	return l.level <= zapcore.WarnLevel
 }
 
+func (l *zapLogger) Error(message string) {
+	l.sugaredLogger.Errorf(message)
+}
+
 func (l *zapLogger) Errorf(format string, args ...interface{}) {
 	l.sugaredLogger.Errorf(format, args...)
 }
@@ -119,6 +140,10 @@ func (l *zapLogger) IsError() bool {
 	return l.level <= zapcore.ErrorLevel
 }
 
+func (l *zapLogger) Fatal(message string) {
+	l.sugaredLogger.Fatal(message)
+}
+
 func (l *zapLogger) Fatalf(format string, args ...interface{}) {
 	l.sugaredLogger.Fatalf(format, args...)
 }
@@ -127,6 +152,10 @@ func (l *zapLogger) IsFatal() bool {
 	return l.level <= zapcore.FatalLevel
 }
 
+func (l *zapLogger) Panic(message string) {
+	l.sugaredLogger.Panic(message)
+}
+
 func (l *zapLogger) Panicf(format string, args ...interface{}) {
 	l.sugaredLogger.Panicf(format, args...)
 }
@@ -155,3 +184,15 @@ func (l *zapLogger) WithError(err error) Logger {
 	}
 	return l.WithFields(Fields{l.errorKey: err.Error()})
 }
+
+func (l *zapLogger) WithContext(ctx context.Context) Logger {
+	fields := ctx.Value(ContextLogTag)
+	if fields == nil {
+		return l
+	}
+	maps := fields.(Fields)
+	if len(maps) > 0 {
+		return l.WithFields(maps)
+	}
+	return l
+}