Decoupled logrus and added a logger interface

- `producer.Config` now takes a producer.Logger interface instead of
a Logrus instance.
- If not logger is provided to config, producer uses a standard library
logger by default (`producer.StandardLogger`)
- `loggers` sub package ships implementations for zap and logrus.

README.md

@@ -3,6 +3,7 @@
 and using the same aggregation format that [KPL][kpl-url] use.  
 
 ### Useful links
+- [Documentation][godoc-url]
 - [Aggregation format][aggregation-format-url]
 - [Considerations When Using KPL Aggregation][kpl-aggregation]
 - [Consumer De-aggregation][de-aggregation]
@@ -22,13 +23,11 @@ import (
 )
 
 func main() {
-	log := logrus.New()
 	client := kinesis.New(session.New(aws.NewConfig()))
 	pr := producer.New(&producer.Config{
 		StreamName:   "test",
 		BacklogCount: 2000,
-		Client:       client,
-		Logger:       log,
+		Client:       client
 	})
 
 	pr.Start()
@@ -55,6 +54,25 @@ func main() {
 }
 ```
 
+#### Using custom logger
+`producer.Config` takes an optional `logging.Logger` implementation.
+
+```go
+customLogger := &CustomLogger{}
+
+&producer.Config{
+  StreamName:   "test",
+  BacklogCount: 2000,
+  Client:       client,
+  Logger:       customLogger,
+}
+```
+
+kinesis-producer ships with three logger implementations.
+
+- `producer.Standard` used the standard library logger
+- `loggers.Logrus` uses logrus logger
+- `loggers.Zap` uses zap logger
 
 ### License
 MIT

config.go

@@ -1,10 +1,11 @@
 package producer
 
 import (
+	"log"
+	"os"
 	"time"
 
 	k "github.com/aws/aws-sdk-go/service/kinesis"
-	"github.com/sirupsen/logrus"
 )
 
 // Constants and default configuration take from:
@@ -54,8 +55,8 @@ type Config struct {
 	// Number of requests to sent concurrently. Default to 24.
 	MaxConnections int
 
-	// Logger is the logger used. Default to logrus.Log.
-	Logger logrus.FieldLogger
+	// Logger is the logger used. Default to producer.Logger.
+	Logger Logger
 
 	// Enabling verbose logging. Default to false.
 	Verbose bool
@@ -67,7 +68,7 @@ type Config struct {
 // defaults for configuration
 func (c *Config) defaults() {
 	if c.Logger == nil {
-		c.Logger = logrus.New()
+		c.Logger = &StandardLogger{log.New(os.Stdout, "", log.LstdFlags)}
 	}
 	if c.BatchCount == 0 {
 		c.BatchCount = maxRecordsPerRequest

example_test.go

@@ -1,22 +1,24 @@
 package producer
 
 import (
+	"log"
+	"os"
 	"time"
 
+	"github.com/a8m/kinesis-producer/logging"
 	"github.com/aws/aws-sdk-go/aws"
 	"github.com/aws/aws-sdk-go/aws/session"
 	"github.com/aws/aws-sdk-go/service/kinesis"
-	"github.com/sirupsen/logrus"
 )
 
 func ExampleSimple() {
-	log := logrus.New()
+	logger := &logging.Standard{log.New(os.Stdout, "", log.LstdFlags)}
 	client := kinesis.New(session.New(aws.NewConfig()))
 	pr := New(&Config{
 		StreamName:   "test",
 		BacklogCount: 2000,
 		Client:       client,
-		Logger:       log,
+		Logger:       logger,
 	})
 
 	pr.Start()
@@ -25,15 +27,15 @@ func ExampleSimple() {
 	go func() {
 		for r := range pr.NotifyFailures() {
 			// r contains `Data`, `PartitionKey` and `Error()`
-			log.Error(r)
+			logger.Error("detected put failure", r.error)
 		}
 	}()
 
 	go func() {
 		for i := 0; i < 5000; i++ {
 			err := pr.Put([]byte("foo"), "bar")
 			if err != nil {
-				log.WithError(err).Fatal("error producing")
+				logger.Error("error producing", err)
 			}
 		}
 	}()

logger.go

@@ -0,0 +1,21 @@
+package producer
+
+import (
+	"fmt"
+)
+
+// Logger represents a simple interface used by kinesis-producer to handle logging
+type Logger interface {
+	Info(msg string, values ...Value)
+	Error(msg string, err error, values ...Value)
+}
+
+// Value represents a key:value pair used by the Logger interface
+type Value struct {
+	Name  string
+	Value interface{}
+}
+
+func (v Value) String() string {
+	return fmt.Sprintf(" %s=%s", v.Name, v.Value)
+}

loggers/logrus.go

@@ -0,0 +1,29 @@
+package loggers
+
+import (
+	producer "github.com/a8m/kinesis-producer"
+	"github.com/sirupsen/logrus"
+)
+
+// Logrus implements a logurs.Logger for kinesis-producer
+type Logrus struct {
+	Logger *logrus.Logger
+}
+
+// Info logs a message
+func (l *Logrus) Info(msg string, args ...producer.Value) {
+	l.Logger.WithFields(l.valuesToFields(args...)).Info(msg)
+}
+
+// Error logs an error
+func (l *Logrus) Error(msg string, err error, args ...producer.Value) {
+	l.Logger.WithError(err).WithFields(l.valuesToFields(args...)).Error(msg)
+}
+
+func (l *Logrus) valuesToFields(values ...producer.Value) logrus.Fields {
+	fields := logrus.Fields{}
+	for _, v := range values {
+		fields[v.Name] = v.Value
+	}
+	return fields
+}

loggers/zap.go

@@ -0,0 +1,32 @@
+package loggers
+
+import (
+	"go.uber.org/zap"
+
+	producer "github.com/a8m/kinesis-producer"
+)
+
+// Zap implements a logurs.Logger for kinesis-producer
+type Zap struct {
+	Logger *zap.Logger
+}
+
+// Info logs a message
+func (l *Zap) Info(msg string, values ...producer.Value) {
+	l.Logger.Info(msg, l.valuesToFields(values)...)
+}
+
+// Error logs an error
+func (l *Zap) Error(msg string, err error, values ...producer.Value) {
+	fields := l.valuesToFields(values)
+	fields = append(fields, zap.Error(err))
+	l.Logger.Info(msg, fields...)
+}
+
+func (l *Zap) valuesToFields(values []producer.Value) []zap.Field {
+	fields := make([]zap.Field, len(values))
+	for i, v := range values {
+		fields[i] = zap.Any(v.Name, v.Value)
+	}
+	return fields
+}

producer.go

@@ -8,10 +8,10 @@ package producer
 
 import (
 	"errors"
+	"fmt"
 	"sync"
 	"time"
 
-	"github.com/sirupsen/logrus"
 	"github.com/aws/aws-sdk-go/service/kinesis"
 	"github.com/jpillora/backoff"
 )
@@ -92,7 +92,7 @@ func (p *Producer) Put(data []byte, partitionKey string) error {
 		p.Lock()
 		if needToDrain {
 			if record, err = p.aggregator.Drain(); err != nil {
-				p.Logger.WithError(err).Error("drain aggregator")
+				p.Logger.Error("drain aggregator", err)
 			}
 		}
 		p.aggregator.Put(data, partitionKey)
@@ -129,7 +129,7 @@ func (p *Producer) NotifyFailures() <-chan *FailureRecord {
 
 // Start the producer
 func (p *Producer) Start() {
-	p.Logger.WithField("stream", p.StreamName).Info("starting producer")
+	p.Logger.Info("starting producer", Value{"stream", p.StreamName})
 	go p.loop()
 }
 
@@ -138,7 +138,7 @@ func (p *Producer) Stop() {
 	p.Lock()
 	p.stopped = true
 	p.Unlock()
-	p.Logger.WithField("backlog", len(p.records)).Info("stopping producer")
+	p.Logger.Info("stopping producer", Value{"backlog", len(p.records)})
 
 	// drain
 	if record, ok := p.drainIfNeed(); ok {
@@ -225,7 +225,7 @@ func (p *Producer) drainIfNeed() (*kinesis.PutRecordsRequestEntry, bool) {
 		record, err := p.aggregator.Drain()
 		p.Unlock()
 		if err != nil {
-			p.Logger.WithError(err).Error("drain aggregator")
+			p.Logger.Error("drain aggregator", err)
 		} else {
 			return record, true
 		}
@@ -243,14 +243,14 @@ func (p *Producer) flush(records []*kinesis.PutRecordsRequestEntry, reason strin
 	defer p.semaphore.release()
 
 	for {
-		p.Logger.WithField("reason", reason).Infof("flush %v records", len(records))
+		p.Logger.Info("flushing records", Value{"reason", reason}, Value{"records", len(records)})
 		out, err := p.Client.PutRecords(&kinesis.PutRecordsInput{
 			StreamName: &p.StreamName,
 			Records:    records,
 		})
 
 		if err != nil {
-			p.Logger.WithError(err).Error("flush")
+			p.Logger.Error("flush", err)
 			p.RLock()
 			notify := p.notify
 			p.RUnlock()
@@ -262,15 +262,15 @@ func (p *Producer) flush(records []*kinesis.PutRecordsRequestEntry, reason strin
 
 		if p.Verbose {
 			for i, r := range out.Records {
-				fields := make(logrus.Fields)
+				values := make([]Value, 2)
 				if r.ErrorCode != nil {
-					fields["ErrorCode"] = *r.ErrorCode
-					fields["ErrorMessage"] = *r.ErrorMessage
+					values[0] = Value{"ErrorCode", *r.ErrorCode}
+					values[1] = Value{"ErrorMessage", *r.ErrorMessage}
 				} else {
-					fields["ShardId"] = *r.ShardId
-					fields["SequenceNumber"] = *r.SequenceNumber
+					values[0] = Value{"ShardId", *r.ShardId}
+					values[1] = Value{"SequenceNumber", *r.SequenceNumber}
 				}
-				p.Logger.WithFields(fields).Infof("Result[%d]", i)
+				p.Logger.Info(fmt.Sprintf("Result[%d]", i), values...)
 			}
 		}
 
@@ -281,11 +281,11 @@ func (p *Producer) flush(records []*kinesis.PutRecordsRequestEntry, reason strin
 
 		duration := b.Duration()
 
-		p.Logger.WithFields(logrus.Fields{
-			"failures": failed,
-			"backoff":  duration.String(),
-		}).Warn("put failures")
-
+		p.Logger.Info(
+			"put failures",
+			Value{"failures", failed},
+			Value{"backoff", duration.String()},
+		)
 		time.Sleep(duration)
 
 		// change the logging state for the next itertion

standard.go

@@ -0,0 +1,30 @@
+package producer
+
+import (
+	"fmt"
+	"log"
+	"strings"
+)
+
+// StandardLogger implements the Logger interface using standard library loggers
+type StandardLogger struct {
+	Logger *log.Logger
+}
+
+// Info prints log message to screen
+func (l *StandardLogger) Info(msg string, values ...Value) {
+	l.Logger.Print(msg, l.valuesToString(values...))
+}
+
+// Error prints log message to screen
+func (l *StandardLogger) Error(msg string, err error, values ...Value) {
+	l.Logger.Print(msg, l.valuesToString(values...), err)
+}
+
+func (l *StandardLogger) valuesToString(values ...Value) string {
+	parts := make([]string, len(values))
+	for i, v := range values {
+		parts[i] = fmt.Sprint(v)
+	}
+	return strings.Join(parts, ", ")
+}