Add support for connection initialisation.

README.md

@@ -11,7 +11,10 @@ Example 1:
     import "github.com/vmihailenco/redis"
 
 
-    redisClient := redis.NewTCPClient(":6379", "", 0)
+    address := ":6379"
+    password := "secret"
+    db := 0
+    redisClient := redis.NewTCPClient(address, password, db)
 
 Example 2:
 
@@ -29,7 +32,7 @@ Example 2:
         return nil
     }
 
-    initConn := func(client *Client) error {
+    initConn := func(client *redis.Client) error {
          _, err := client.Auth("foo").Reply()
          if err != nil {
              return err
@@ -45,7 +48,7 @@ Example 2:
 
     redisClient := redis.NewClient(openConn, closeConn, initConn)
 
-`closeConn` and `initConn` functions can be `nil`.
+Both `closeConn` and `initConn` functions can be `nil`.
 
 Running commands
 ----------------
@@ -199,4 +202,4 @@ Connection pool
 
 Client uses connection pool with default capacity of 10 connections. To change pool capacity:
 
-    redisClient.ConnPool.MaxCap = 1
+    redisClient.ConnPool.(*redis.MultiConnPool).MaxCap = 1

connpool.go

@@ -21,7 +21,16 @@ func NewConn(rw io.ReadWriter) *Conn {
 	}
 }
 
-type ConnPool struct {
+type ConnPool interface {
+	Get() (*Conn, bool, error)
+	Add(*Conn)
+	Remove(*Conn)
+	Len() int
+}
+
+//------------------------------------------------------------------------------
+
+type MultiConnPool struct {
 	Logger      *log.Logger
 	cond        *sync.Cond
 	conns       []*Conn
@@ -30,13 +39,13 @@ type ConnPool struct {
 	cap, MaxCap int64
 }
 
-func NewConnPool(openConn OpenConnFunc, closeConn CloseConnFunc, maxCap int64) *ConnPool {
+func NewMultiConnPool(openConn OpenConnFunc, closeConn CloseConnFunc, maxCap int64) *MultiConnPool {
 	logger := log.New(
 		os.Stdout,
 		"redis.connpool: ",
 		log.Ldate|log.Ltime|log.Lshortfile,
 	)
-	return &ConnPool{
+	return &MultiConnPool{
 		cond:      sync.NewCond(&sync.Mutex{}),
 		Logger:    logger,
 		conns:     make([]*Conn, 0),
@@ -46,7 +55,7 @@ func NewConnPool(openConn OpenConnFunc, closeConn CloseConnFunc, maxCap int64) *
 	}
 }
 
-func (p *ConnPool) Get() (*Conn, bool, error) {
+func (p *MultiConnPool) Get() (*Conn, bool, error) {
 	p.cond.L.Lock()
 	defer p.cond.L.Unlock()
 
@@ -72,14 +81,14 @@ func (p *ConnPool) Get() (*Conn, bool, error) {
 	return conn, false, nil
 }
 
-func (p *ConnPool) Add(conn *Conn) {
+func (p *MultiConnPool) Add(conn *Conn) {
 	p.cond.L.Lock()
 	defer p.cond.L.Unlock()
 	p.conns = append(p.conns, conn)
 	p.cond.Signal()
 }
 
-func (p *ConnPool) Remove(conn *Conn) {
+func (p *MultiConnPool) Remove(conn *Conn) {
 	p.cond.L.Lock()
 	p.cap--
 	p.cond.Signal()
@@ -90,6 +99,28 @@ func (p *ConnPool) Remove(conn *Conn) {
 	}
 }
 
-func (p *ConnPool) Len() int {
+func (p *MultiConnPool) Len() int {
 	return len(p.conns)
 }
+
+//------------------------------------------------------------------------------
+
+type OneConnPool struct {
+	conn *Conn
+}
+
+func NewOneConnPool(conn *Conn) *OneConnPool {
+	return &OneConnPool{conn: conn}
+}
+
+func (p *OneConnPool) Get() (*Conn, bool, error) {
+	return p.conn, false, nil
+}
+
+func (p *OneConnPool) Add(conn *Conn) {}
+
+func (p *OneConnPool) Remove(conn *Conn) {}
+
+func (p *OneConnPool) Len() int {
+	return 1
+}

redis.go

@@ -28,6 +28,10 @@ func TLSConnector(addr string, tlsConfig *tls.Config) OpenConnFunc {
 }
 
 func AuthSelectFunc(password string, db int64) InitConnFunc {
+	if password == "" && db < 0 {
+		return nil
+	}
+
 	return func(client *Client) error {
 		if password != "" {
 			_, err := client.Auth(password).Reply()
@@ -36,9 +40,11 @@ func AuthSelectFunc(password string, db int64) InitConnFunc {
 			}
 		}
 
-		_, err := client.Select(db).Reply()
-		if err != nil {
-			return err
+		if db >= 0 {
+			_, err := client.Select(db).Reply()
+			if err != nil {
+				return err
+			}
 		}
 
 		return nil
@@ -51,7 +57,7 @@ func createReader() (*bufreader.Reader, error) {
 
 type Client struct {
 	mtx      sync.Mutex
-	ConnPool *ConnPool
+	ConnPool ConnPool
 	InitConn InitConnFunc
 
 	reqs []Req
@@ -59,7 +65,7 @@ type Client struct {
 
 func NewClient(openConn OpenConnFunc, closeConn CloseConnFunc, initConn InitConnFunc) *Client {
 	return &Client{
-		ConnPool: NewConnPool(openConn, closeConn, 10),
+		ConnPool: NewMultiConnPool(openConn, closeConn, 10),
 		InitConn: initConn,
 	}
 }
@@ -76,6 +82,23 @@ func NewTLSClient(addr string, tlsConfig *tls.Config, password string, db int64)
 	)
 }
 
+func (c *Client) conn() (*Conn, error) {
+	conn, isNew, err := c.ConnPool.Get()
+	if err != nil {
+		return nil, err
+	}
+	if isNew && c.InitConn != nil {
+		client := &Client{
+			ConnPool: NewOneConnPool(conn),
+		}
+		err = c.InitConn(client)
+		if err != nil {
+			return nil, err
+		}
+	}
+	return conn, nil
+}
+
 func (c *Client) WriteReq(buf []byte, conn *Conn) error {
 	_, err := conn.RW.Write(buf)
 	return err
@@ -120,7 +143,7 @@ func (c *Client) Queue(req Req) {
 }
 
 func (c *Client) Run(req Req) {
-	conn, _, err := c.ConnPool.Get()
+	conn, err := c.conn()
 	if err != nil {
 		req.SetErr(err)
 		return
@@ -154,7 +177,7 @@ func (c *Client) RunQueued() ([]Req, error) {
 	c.reqs = make([]Req, 0)
 	c.mtx.Unlock()
 
-	conn, _, err := c.ConnPool.Get()
+	conn, err := c.conn()
 	if err != nil {
 		return nil, err
 	}
@@ -223,7 +246,7 @@ func (c *Client) Exec() ([]Req, error) {
 	c.reqs = make([]Req, 0)
 	c.mtx.Unlock()
 
-	conn, _, err := c.ConnPool.Get()
+	conn, err := c.conn()
 	if err != nil {
 		return nil, err
 	}

redis_test.go

@@ -1,6 +1,8 @@
 package redis_test
 
 import (
+	"io"
+	"net"
 	"strconv"
 	"sync"
 	"testing"
@@ -24,7 +26,7 @@ func Test(t *testing.T) { TestingT(t) }
 //------------------------------------------------------------------------------
 
 func (t *RedisTest) SetUpTest(c *C) {
-	t.client = redis.NewTCPClient(":6379", "", 0)
+	t.client = redis.NewTCPClient(":6379", "", -1)
 	_, err := t.client.Flushdb().Reply()
 	c.Check(err, IsNil)
 
@@ -38,6 +40,24 @@ func (t *RedisTest) TearDownTest(c *C) {
 
 //------------------------------------------------------------------------------
 
+func (t *RedisTest) TestInitConn(c *C) {
+	openConn := func() (io.ReadWriter, error) {
+		return net.Dial("tcp", ":6379")
+	}
+
+	isInitConnCalled := false
+	initConn := func(client *redis.Client) error {
+		isInitConnCalled = true
+		return nil
+	}
+
+	client := redis.NewClient(openConn, nil, initConn)
+	pong, err := client.Ping().Reply()
+	c.Check(err, IsNil)
+	c.Check(pong, Equals, "PONG")
+	c.Check(isInitConnCalled, Equals, true)
+}
+
 func (t *RedisTest) TestRunWithMissingReplyPart(c *C) {
 	req := t.client.Set("foo", "bar")
 
@@ -1667,6 +1687,25 @@ func (t *RedisTest) BenchmarkRedisGet(c *C) {
 	}
 }
 
+func (t *RedisTest) BenchmarkRedisMGet(c *C) {
+	c.StopTimer()
+
+	_, err := t.client.MSet("foo1", "bar1", "foo2", "bar2").Reply()
+	c.Check(err, IsNil)
+
+	for i := 0; i < 10; i++ {
+		values, err := t.client.MGet("foo1", "foo2").Reply()
+		c.Check(err, IsNil)
+		c.Check(values, DeepEquals, []interface{}{"bar1", "bar2"})
+	}
+
+	c.StartTimer()
+
+	for i := 0; i < c.N; i++ {
+		t.client.MGet("foo1", "foo2").Reply()
+	}
+}
+
 func (t *RedisTest) BenchmarkRedisWriteRead(c *C) {
 	c.StopTimer()