Extract pipeline and multi/exec support to separate files.

pipeline.go

@@ -0,0 +1,75 @@
+package redis
+
+type PipelineClient struct {
+	*Client
+}
+
+func (c *Client) PipelineClient() (*PipelineClient, error) {
+	return &PipelineClient{
+		Client: &Client{
+			BaseClient: &BaseClient{
+				ConnPool: c.ConnPool,
+				InitConn: c.InitConn,
+				reqs:     make([]Req, 0),
+			},
+		},
+	}, nil
+}
+
+func (c *PipelineClient) Close() error {
+	return nil
+}
+
+func (c *PipelineClient) RunQueued() ([]Req, error) {
+	c.mtx.Lock()
+	if len(c.reqs) == 0 {
+		c.mtx.Unlock()
+		return c.reqs, nil
+	}
+	reqs := c.reqs
+	c.reqs = make([]Req, 0)
+	c.mtx.Unlock()
+
+	conn, err := c.conn()
+	if err != nil {
+		return nil, err
+	}
+
+	err = c.RunReqs(reqs, conn)
+	if err != nil {
+		c.ConnPool.Remove(conn)
+		return nil, err
+	}
+
+	c.ConnPool.Add(conn)
+	return reqs, nil
+}
+
+func (c *PipelineClient) RunReqs(reqs []Req, conn *Conn) error {
+	var multiReq []byte
+	if len(reqs) == 1 {
+		multiReq = reqs[0].Req()
+	} else {
+		multiReq = make([]byte, 0, 1024)
+		for _, req := range reqs {
+			multiReq = append(multiReq, req.Req()...)
+		}
+	}
+
+	err := c.WriteReq(multiReq, conn)
+	if err != nil {
+		return err
+	}
+
+	for i := 0; i < len(reqs); i++ {
+		req := reqs[i]
+		val, err := req.ParseReply(conn.Rd)
+		if err != nil {
+			req.SetErr(err)
+		} else {
+			req.SetVal(val)
+		}
+	}
+
+	return nil
+}