add unittests and bug fix

redis/parser/parser.go

@@ -2,6 +2,7 @@ package parser
 
 import (
 	"bufio"
+	"bytes"
 	"errors"
 	"github.com/hdt3213/godis/interface/redis"
 	"github.com/hdt3213/godis/lib/logger"
@@ -17,19 +18,25 @@ type Payload struct {
 	Err  error
 }
 
-func Parse(reader io.Reader) <-chan *Payload {
+// ParseStream reads data from io.Reader and send payloads through channel
+func ParseStream(reader io.Reader) <-chan *Payload {
 	ch := make(chan *Payload)
-	go func() {
-		defer func() {
-			if err := recover(); err != nil {
-				logger.Error(debug.Stack())
-			}
-		}()
-		parse0(reader, ch)
-	}()
+	go parse0(reader, ch)
 	return ch
 }
 
+// ParseOne reads data from []byte and return the first payload
+func ParseOne(data []byte) (redis.Reply, error) {
+	ch := make(chan *Payload)
+	reader := bytes.NewReader(data)
+	go parse0(reader, ch)
+	payload := <-ch // parse0 will close the channel
+	if payload == nil {
+		return nil, errors.New("no reply")
+	}
+	return payload.Data, payload.Err
+}
+
 type readState struct {
 	downloading       bool
 	expectedArgsCount int
@@ -44,6 +51,11 @@ func (s *readState) finished() bool {
 }
 
 func parse0(reader io.Reader, ch chan<- *Payload) {
+	defer func() {
+		if err := recover(); err != nil {
+			logger.Error(string(debug.Stack()))
+		}
+	}()
 	bufReader := bufio.NewReader(reader)
 	var state readState
 	var err error

redis/parser/parser_test.go

@@ -9,7 +9,7 @@ import (
 	"testing"
 )
 
-func TestParse(t *testing.T) {
+func TestParseStream(t *testing.T) {
 	replies := []redis.Reply{
 		reply.MakeIntReply(1),
 		reply.MakeStatusReply("OK"),
@@ -33,7 +33,7 @@ func TestParse(t *testing.T) {
 		[]byte("set"), []byte("a"), []byte("a"),
 	}))
 
-	ch := Parse(bytes.NewReader(reqs.Bytes()))
+	ch := ParseStream(bytes.NewReader(reqs.Bytes()))
 	i := 0
 	for payload := range ch {
 		if payload.Err != nil {
@@ -54,3 +54,28 @@ func TestParse(t *testing.T) {
 		}
 	}
 }
+
+func TestParseOne(t *testing.T) {
+	replies := []redis.Reply{
+		reply.MakeIntReply(1),
+		reply.MakeStatusReply("OK"),
+		reply.MakeErrReply("ERR unknown"),
+		reply.MakeBulkReply([]byte("a\r\nb")), // test binary safe
+		reply.MakeNullBulkReply(),
+		reply.MakeMultiBulkReply([][]byte{
+			[]byte("a"),
+			[]byte("\r\n"),
+		}),
+		reply.MakeEmptyMultiBulkReply(),
+	}
+	for _, re := range replies {
+		result, err := ParseOne(re.ToBytes())
+		if err != nil {
+			t.Error(err)
+			continue
+		}
+		if !utils.BytesEquals(result.ToBytes(), re.ToBytes()) {
+			t.Error("parse failed: " + string(re.ToBytes()))
+		}
+	}
+}