Merge pull request zeromicro#53 from algobot76/document-pusher

doc: add missing comments in pusher.go

Author: kevwan

kq/pusher.go

@@ -25,6 +25,7 @@ type (
 	}
 )
 
+// NewPusher returns a Pusher with the given Kafka addresses and topic.
 func NewPusher(addrs []string, topic string, opts ...PushOption) *Pusher {
 	producer := &kafka.Writer{
 		Addr:        kafka.TCP(addrs...),
@@ -49,6 +50,7 @@ func NewPusher(addrs []string, topic string, opts ...PushOption) *Pusher {
 	return pusher
 }
 
+// Close closes the Pusher and releases any resources used by it.
 func (p *Pusher) Close() error {
 	if p.executor != nil {
 		p.executor.Flush()
@@ -57,13 +59,15 @@ func (p *Pusher) Close() error {
 	return p.producer.Close()
 }
 
+// Name returns the name of the Kafka topic that the Pusher is sending messages to.
 func (p *Pusher) Name() string {
 	return p.topic
 }
 
+// Push sends a message to the Kafka topic.
 func (p *Pusher) Push(v string) error {
 	msg := kafka.Message{
-		Key:   []byte(strconv.FormatInt(time.Now().UnixNano(), 10)),
+		Key:   []byte(strconv.FormatInt(time.Now().UnixNano(), 10)), // current timestamp
 		Value: []byte(v),
 	}
 	if p.executor != nil {
@@ -73,12 +77,14 @@ func (p *Pusher) Push(v string) error {
 	}
 }
 
+// WithChunkSize customizes the Pusher with the given chunk size.
 func WithChunkSize(chunkSize int) PushOption {
 	return func(options *chunkOptions) {
 		options.chunkSize = chunkSize
 	}
 }
 
+// WithFlushInterval customizes the Pusher with the given flush interval.
 func WithFlushInterval(interval time.Duration) PushOption {
 	return func(options *chunkOptions) {
 		options.flushInterval = interval