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|
package kafka
import (
"context"
"errors"
"io"
"strings"
"testing"
"time"
)
func TestWriter(t *testing.T) {
t.Parallel()
tests := []struct {
scenario string
function func(*testing.T)
}{
{
scenario: "closing a writer right after creating it returns promptly with no error",
function: testWriterClose,
},
{
scenario: "writing 1 message through a writer using round-robin balancing produces 1 message to the first partition",
function: testWriterRoundRobin1,
},
{
scenario: "running out of max attempts should return an error",
function: testWriterMaxAttemptsErr,
},
}
for _, test := range tests {
testFunc := test.function
t.Run(test.scenario, func(t *testing.T) {
t.Parallel()
testFunc(t)
})
}
}
func newTestWriter(config WriterConfig) *Writer {
if len(config.Brokers) == 0 {
config.Brokers = []string{"localhost:9092"}
}
return NewWriter(config)
}
func testWriterClose(t *testing.T) {
const topic = "test-writer-0"
createTopic(t, topic, 1)
w := newTestWriter(WriterConfig{
Topic: topic,
})
if err := w.Close(); err != nil {
t.Error(err)
}
}
func testWriterRoundRobin1(t *testing.T) {
const topic = "test-writer-1"
createTopic(t, topic, 1)
offset, err := readOffset(topic, 0)
if err != nil {
t.Fatal(err)
}
w := newTestWriter(WriterConfig{
Topic: topic,
Balancer: &RoundRobin{},
})
defer w.Close()
if err := w.WriteMessages(context.Background(), Message{
Value: []byte("Hello World!"),
}); err != nil {
t.Error(err)
return
}
msgs, err := readPartition(topic, 0, offset)
if err != nil {
t.Error("error reading partition", err)
return
}
if len(msgs) != 1 {
t.Error("bad messages in partition", msgs)
return
}
for _, m := range msgs {
if string(m.Value) != "Hello World!" {
t.Error("bad messages in partition", msgs)
break
}
}
}
type fakeWriter struct{}
func (f *fakeWriter) messages() chan<- writerMessage {
ch := make(chan writerMessage, 1)
go func() {
for {
msg := <-ch
msg.res <- &writerError{
err: errors.New("bad attempt"),
}
}
}()
return ch
}
func (f *fakeWriter) close() {
}
func testWriterMaxAttemptsErr(t *testing.T) {
const topic = "test-writer-2"
createTopic(t, topic, 1)
w := newTestWriter(WriterConfig{
Topic: topic,
MaxAttempts: 1,
Balancer: &RoundRobin{},
newPartitionWriter: func(p int, config WriterConfig, stats *writerStats) partitionWriter {
return &fakeWriter{}
},
})
defer w.Close()
if err := w.WriteMessages(context.Background(), Message{
Value: []byte("Hello World!"),
}); err == nil {
t.Error("expected error")
return
} else if err != nil {
if !strings.Contains(err.Error(), "bad attempt") {
t.Errorf("unexpected error: %s", err)
return
}
}
}
func readOffset(topic string, partition int) (offset int64, err error) {
var conn *Conn
if conn, err = DialLeader(context.Background(), "tcp", "localhost:9092", topic, partition); err != nil {
return
}
defer conn.Close()
offset, err = conn.ReadLastOffset()
return
}
func readPartition(topic string, partition int, offset int64) (msgs []Message, err error) {
var conn *Conn
if conn, err = DialLeader(context.Background(), "tcp", "localhost:9092", topic, partition); err != nil {
return
}
defer conn.Close()
conn.Seek(offset, SeekAbsolute)
conn.SetReadDeadline(time.Now().Add(100 * time.Millisecond))
batch := conn.ReadBatch(0, 1000000000)
defer batch.Close()
for {
var msg Message
if msg, err = batch.ReadMessage(); err != nil {
if err == io.EOF {
err = nil
}
return
}
msgs = append(msgs, msg)
}
}
|
