feat: Adding public logging API

CHANGELOG.md

@@ -6,7 +6,8 @@
 
 ### Features
 1. [#165](https://github.com/influxdata/influxdb-client-go/pull/165) Allow overriding the http.Client for the http service.
-1. [#179](https://github.com/influxdata/influxdb-client-go/pull/179) Unifying retry strategy among InfluxDB 2 clients: added exponential backoff. 
+1. [#179](https://github.com/influxdata/influxdb-client-go/pull/179) Unifying retry strategy among InfluxDB 2 clients: added exponential backoff.
+1. [#180](https://github.com/influxdata/influxdb-client-go/pull/180) Provided public logger API to enable overriding logging. It is also possible to disable logging. 
 
 ### Bug fixes 
 1. [#175](https://github.com/influxdata/influxdb-client-go/pull/175) Fixed WriteAPIs management. Keeping single instance for each org and bucket pair.

api/query.go

@@ -26,6 +26,7 @@ import (
 	"github.com/influxdata/influxdb-client-go/api/query"
 	"github.com/influxdata/influxdb-client-go/domain"
 	ihttp "github.com/influxdata/influxdb-client-go/internal/http"
+	"github.com/influxdata/influxdb-client-go/internal/log"
 )
 
 const (
@@ -74,6 +75,7 @@ func (q *queryAPI) QueryRaw(ctx context.Context, query string, dialect *domain.D
 	if err != nil {
 		return "", err
 	}
+	log.Debugf("Query: %s", string(qrJSON))
 	var body string
 	perror := q.httpService.PostRequest(ctx, queryURL, bytes.NewReader(qrJSON), func(req *http.Request) {
 		req.Header.Set("Content-Type", "application/json")
@@ -123,6 +125,7 @@ func (q *queryAPI) Query(ctx context.Context, query string) (*QueryTableResult,
 	if err != nil {
 		return nil, err
 	}
+	log.Debugf("Query: %s", string(qrJSON))
 	perror := q.httpService.PostRequest(ctx, queryURL, bytes.NewReader(qrJSON), func(req *http.Request) {
 		req.Header.Set("Content-Type", "application/json")
 		req.Header.Set("Accept-Encoding", "gzip")

api/write.go

@@ -94,7 +94,7 @@ func (w *WriteAPIImpl) waitForFlushing() {
 		if writeBuffInfo.writeBuffLen == 0 {
 			break
 		}
-		log.Log.Info("Waiting buffer is flushed")
+		log.Info("Waiting buffer is flushed")
 		time.Sleep(time.Millisecond)
 	}
 	for {
@@ -103,13 +103,13 @@ func (w *WriteAPIImpl) waitForFlushing() {
 		if writeBuffInfo.writeBuffLen == 0 {
 			break
 		}
-		log.Log.Info("Waiting buffer is flushed")
+		log.Info("Waiting buffer is flushed")
 		time.Sleep(time.Millisecond)
 	}
 }
 
 func (w *WriteAPIImpl) bufferProc() {
-	log.Log.Info("Buffer proc started")
+	log.Info("Buffer proc started")
 	ticker := time.NewTicker(time.Duration(w.writeOptions.FlushInterval()) * time.Millisecond)
 x:
 	for {
@@ -132,21 +132,21 @@ x:
 			w.bufferInfoCh <- buffInfo
 		}
 	}
-	log.Log.Info("Buffer proc finished")
+	log.Info("Buffer proc finished")
 	w.doneCh <- struct{}{}
 }
 
 func (w *WriteAPIImpl) flushBuffer() {
 	if len(w.writeBuffer) > 0 {
-		log.Log.Info("sending batch")
+		log.Info("sending batch")
 		batch := iwrite.NewBatch(buffer(w.writeBuffer), w.writeOptions.RetryInterval())
 		w.writeCh <- batch
 		w.writeBuffer = w.writeBuffer[:0]
 	}
 }
 
 func (w *WriteAPIImpl) writeProc() {
-	log.Log.Info("Write proc started")
+	log.Info("Write proc started")
 x:
 	for {
 		select {
@@ -156,14 +156,14 @@ x:
 				w.errCh <- err
 			}
 		case <-w.writeStop:
-			log.Log.Info("Write proc: received stop")
+			log.Info("Write proc: received stop")
 			break x
 		case buffInfo := <-w.writeInfoCh:
 			buffInfo.writeBuffLen = len(w.writeCh)
 			w.writeInfoCh <- buffInfo
 		}
 	}
-	log.Log.Info("Write proc finished")
+	log.Info("Write proc finished")
 	w.doneCh <- struct{}{}
 }
 
@@ -205,7 +205,7 @@ func (w *WriteAPIImpl) WriteRecord(line string) {
 func (w *WriteAPIImpl) WritePoint(point *write.Point) {
 	line, err := w.service.EncodePoints(point)
 	if err != nil {
-		log.Log.Errorf("point encoding error: %s\n", err.Error())
+		log.Errorf("point encoding error: %s\n", err.Error())
 	} else {
 		w.bufferCh <- line
 	}

api/write_test.go

@@ -14,8 +14,8 @@ import (
 
 	"github.com/influxdata/influxdb-client-go/api/write"
 	ihttp "github.com/influxdata/influxdb-client-go/internal/http"
-	"github.com/influxdata/influxdb-client-go/internal/log"
 	"github.com/influxdata/influxdb-client-go/internal/test"
+	"github.com/influxdata/influxdb-client-go/log"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 )
@@ -101,7 +101,7 @@ func TestWriteAPIImpl_Write(t *testing.T) {
 
 func TestGzipWithFlushing(t *testing.T) {
 	service := test.NewTestService(t, "http://localhost:8888")
-	log.Log.SetDebugLevel(4)
+	log.Log.SetLogLevel(log.DebugLevel)
 	writeAPI := NewWriteAPI("my-org", "my-bucket", service, write.DefaultOptions().SetBatchSize(5).SetUseGZip(true))
 	points := genPoints(5)
 	for _, p := range points {
@@ -151,7 +151,7 @@ func TestFlushInterval(t *testing.T) {
 
 func TestRetry(t *testing.T) {
 	service := test.NewTestService(t, "http://localhost:8888")
-	log.Log.SetDebugLevel(5)
+	log.Log.SetLogLevel(log.DebugLevel)
 	writeAPI := NewWriteAPI("my-org", "my-bucket", service, write.DefaultOptions().SetBatchSize(5).SetRetryInterval(10000))
 	points := genPoints(15)
 	for i := 0; i < 5; i++ {
@@ -188,7 +188,7 @@ func TestRetry(t *testing.T) {
 
 func TestWriteError(t *testing.T) {
 	service := test.NewTestService(t, "http://localhost:8888")
-	log.Log.SetDebugLevel(3)
+	log.Log.SetLogLevel(log.DebugLevel)
 	service.SetReplyError(&ihttp.Error{
 		StatusCode: 400,
 		Code:       "write",

client.go

@@ -15,7 +15,8 @@ import (
 	"github.com/influxdata/influxdb-client-go/api"
 	"github.com/influxdata/influxdb-client-go/domain"
 	ihttp "github.com/influxdata/influxdb-client-go/internal/http"
-	"github.com/influxdata/influxdb-client-go/internal/log"
+	ilog "github.com/influxdata/influxdb-client-go/internal/log"
+	"github.com/influxdata/influxdb-client-go/log"
 )
 
 // Client provides API to communicate with InfluxDBServer.
@@ -101,8 +102,10 @@ func NewClientWithOptions(serverURL string, authToken string, options *Options)
 		httpService:   service,
 		apiClient:     domain.NewClientWithResponses(service),
 	}
-	log.Log.SetDebugLevel(client.Options().LogLevel())
-	log.Log.Infof("Using URL '%s', token '%s'", serverURL, authToken)
+	if log.Log != nil {
+		log.Log.SetLogLevel(options.LogLevel())
+	}
+	ilog.Infof("Using URL '%s', token '%s'", serverURL, authToken)
 	return client
 }
 func (c *clientImpl) Options() *Options {

internal/http/service.go

@@ -16,6 +16,7 @@ import (
 	"strconv"
 
 	http2 "github.com/influxdata/influxdb-client-go/api/http"
+	"github.com/influxdata/influxdb-client-go/internal/log"
 )
 
 // RequestCallback defines function called after a request is created before any call
@@ -59,7 +60,7 @@ func NewService(serverURL, authorization string, httpOptions *http2.Options) Ser
 		serverAPIURL:  serverAPIURL,
 		serverURL:     serverURL,
 		authorization: authorization,
-		client: httpOptions.HTTPClient(),
+		client:        httpOptions.HTTPClient(),
 	}
 }
 
@@ -114,6 +115,7 @@ func (s *service) DoHTTPRequest(req *http.Request, requestCallback RequestCallba
 }
 
 func (s *service) DoHTTPRequestWithResponse(req *http.Request, requestCallback RequestCallback) (*http.Response, error) {
+	log.Infof("HTTP %s req to %s", req.Method, req.URL.String())
 	req.Header.Set("Authorization", s.authorization)
 	req.Header.Set("User-Agent", UserAgent)
 	if requestCallback != nil {

internal/log/logger.go

@@ -6,61 +6,50 @@
 package log
 
 import (
-	"fmt"
-	"log"
+	ilog "github.com/influxdata/influxdb-client-go/log"
 )
 
-var Log Logger
-
-// Logger provides filtered and categorized logging API.
-// It logs to standard logger, only errors by default
-type Logger struct {
-	debugLevel uint
-}
-
-// SetDebugLevel to filter log messages. Each level mean to log all categories bellow
-// 0 errors , 1 - warning, 2 - info, 3 - debug
-func (l *Logger) SetDebugLevel(debugLevel uint) {
-	l.debugLevel = debugLevel
-}
-
-func (l *Logger) Debugf(format string, v ...interface{}) {
-	if l.debugLevel > 2 {
-		log.Print("[D]! ", fmt.Sprintf(format, v...))
+func Debugf(format string, v ...interface{}) {
+	if ilog.Log != nil {
+		ilog.Log.Debugf(format, v...)
 	}
 }
-func (l *Logger) Debug(msg string) {
-	if l.debugLevel > 2 {
-		log.Print("[D]! ", msg)
+func Debug(msg string) {
+	if ilog.Log != nil {
+		ilog.Log.Debug(msg)
 	}
 }
 
-func (l *Logger) Infof(format string, v ...interface{}) {
-	if l.debugLevel > 1 {
-		log.Print("[I]! ", fmt.Sprintf(format, v...))
+func Infof(format string, v ...interface{}) {
+	if ilog.Log != nil {
+		ilog.Log.Infof(format, v...)
 	}
 }
-func (l *Logger) Info(msg string) {
-	if l.debugLevel > 1 {
-		log.Print("[I]! ", msg)
+func Info(msg string) {
+	if ilog.Log != nil {
+		ilog.Log.Info(msg)
 	}
 }
 
-func (l *Logger) Warnf(format string, v ...interface{}) {
-	if l.debugLevel > 0 {
-		log.Print("[W]! ", fmt.Sprintf(format, v...))
+func Warnf(format string, v ...interface{}) {
+	if ilog.Log != nil {
+		ilog.Log.Warnf(format, v...)
 	}
 }
-func (l *Logger) Warn(msg string) {
-	if l.debugLevel > 0 {
-		log.Print("[W]! ", msg)
+func Warn(msg string) {
+	if ilog.Log != nil {
+		ilog.Log.Warn(msg)
 	}
 }
 
-func (l *Logger) Errorf(format string, v ...interface{}) {
-	log.Print("[E]! ", fmt.Sprintf(format, v...))
+func Errorf(format string, v ...interface{}) {
+	if ilog.Log != nil {
+		ilog.Log.Errorf(format, v...)
+	}
 }
 
-func (l *Logger) Error(msg string) {
-	log.Print("[E]! ", msg)
+func Error(msg string) {
+	if ilog.Log != nil {
+		ilog.Log.Error(msg)
+	}
 }

internal/log/logger_test.go

@@ -0,0 +1,51 @@
+// Copyright 2020 InfluxData, Inc. All rights reserved.
+// Use of this source code is governed by MIT
+// license that can be found in the LICENSE file.
+
+package log_test
+
+import (
+	"log"
+	"strings"
+	"testing"
+
+	ilog "github.com/influxdata/influxdb-client-go/internal/log"
+	dlog "github.com/influxdata/influxdb-client-go/log"
+	"github.com/stretchr/testify/assert"
+)
+
+func TestLogging(t *testing.T) {
+	var sb strings.Builder
+	log.SetOutput(&sb)
+	dlog.Log.SetLogLevel(dlog.DebugLevel)
+	//test default settings
+	ilog.Debug("Debug")
+	ilog.Debugf("Debugf %s %d", "message", 1)
+	ilog.Info("Info")
+	ilog.Infof("Infof %s %d", "message", 2)
+	ilog.Warn("Warn")
+	ilog.Warnf("Warnf %s %d", "message", 3)
+	ilog.Error("Error")
+	ilog.Errorf("Errorf %s %d", "message", 4)
+	assert.True(t, strings.Contains(sb.String(), "Debug"))
+	assert.True(t, strings.Contains(sb.String(), "Debugf message 1"))
+	assert.True(t, strings.Contains(sb.String(), "Info"))
+	assert.True(t, strings.Contains(sb.String(), "Infof message 2"))
+	assert.True(t, strings.Contains(sb.String(), "Warn"))
+	assert.True(t, strings.Contains(sb.String(), "Warnf message 3"))
+	assert.True(t, strings.Contains(sb.String(), "Error"))
+	assert.True(t, strings.Contains(sb.String(), "Errorf message 4"))
+
+	sb.Reset()
+
+	dlog.Log = nil
+	ilog.Debug("Debug")
+	ilog.Debugf("Debugf %s %d", "message", 1)
+	ilog.Info("Info")
+	ilog.Infof("Infof %s %d", "message", 2)
+	ilog.Warn("Warn")
+	ilog.Warnf("Warnf %s %d", "message", 3)
+	ilog.Error("Error")
+	ilog.Errorf("Errorf %s %d", "message", 4)
+	assert.True(t, len(sb.String()) == 0)
+}