Rename Multi to Tx to better reflect the purpose. Fixes #194.

cluster.go

@@ -60,7 +60,7 @@ func (c *ClusterClient) getClients() map[string]*Client {
 
 // Watch creates new transaction and marks the keys to be watched
 // for conditional execution of a transaction.
-func (c *ClusterClient) Watch(keys ...string) (*Multi, error) {
+func (c *ClusterClient) Watch(keys ...string) (*Tx, error) {
 	addr := c.slotMasterAddr(hashtag.Slot(keys[0]))
 	client, err := c.getClient(addr)
 	if err != nil {

commands_test.go

@@ -4,9 +4,6 @@ import (
 	"encoding/json"
 	"fmt"
 	"reflect"
-	"strconv"
-	"sync"
-	"testing"
 	"time"
 
 	. "github.com/onsi/ginkgo"
@@ -2551,63 +2548,6 @@ var _ = Describe("Commands", func() {
 
 	})
 
-	Describe("watch/unwatch", func() {
-
-		It("should WatchUnwatch", func() {
-			var C, N = 10, 1000
-			if testing.Short() {
-				N = 100
-			}
-
-			err := client.Set("key", "0", 0).Err()
-			Expect(err).NotTo(HaveOccurred())
-
-			wg := &sync.WaitGroup{}
-			for i := 0; i < C; i++ {
-				wg.Add(1)
-
-				go func() {
-					defer GinkgoRecover()
-					defer wg.Done()
-
-					multi := client.Multi()
-					defer multi.Close()
-
-					for j := 0; j < N; j++ {
-						val, err := multi.Watch("key").Result()
-						Expect(err).NotTo(HaveOccurred())
-						Expect(val).To(Equal("OK"))
-
-						val, err = multi.Get("key").Result()
-						Expect(err).NotTo(HaveOccurred())
-						Expect(val).NotTo(Equal(redis.Nil))
-
-						num, err := strconv.ParseInt(val, 10, 64)
-						Expect(err).NotTo(HaveOccurred())
-
-						cmds, err := multi.Exec(func() error {
-							multi.Set("key", strconv.FormatInt(num+1, 10), 0)
-							return nil
-						})
-						if err == redis.TxFailedErr {
-							j--
-							continue
-						}
-						Expect(err).NotTo(HaveOccurred())
-						Expect(cmds).To(HaveLen(1))
-						Expect(cmds[0].Err()).NotTo(HaveOccurred())
-					}
-				}()
-			}
-			wg.Wait()
-
-			val, err := client.Get("key").Int64()
-			Expect(err).NotTo(HaveOccurred())
-			Expect(val).To(Equal(int64(C * N)))
-		})
-
-	})
-
 	Describe("Geo add and radius search", func() {
 		BeforeEach(func() {
 			geoAdd := client.GeoAdd(

pool_test.go

@@ -37,16 +37,18 @@ var _ = Describe("pool", func() {
 		perform(1000, func(id int) {
 			var ping *redis.StatusCmd
 
-			multi := client.Multi()
-			cmds, err := multi.Exec(func() error {
-				ping = multi.Ping()
+			tx, err := client.Watch()
+			Expect(err).NotTo(HaveOccurred())
+
+			cmds, err := tx.Exec(func() error {
+				ping = tx.Ping()
 				return nil
 			})
 			Expect(err).NotTo(HaveOccurred())
 			Expect(cmds).To(HaveLen(1))
 			Expect(ping.Err()).NotTo(HaveOccurred())
 			Expect(ping.Val()).To(Equal("PONG"))
-			Expect(multi.Close()).NotTo(HaveOccurred())
+			Expect(tx.Close()).NotTo(HaveOccurred())
 		})
 
 		pool := client.Pool()

race_test.go

@@ -208,4 +208,43 @@ var _ = Describe("races", func() {
 			Expect(err).NotTo(HaveOccurred())
 		})
 	})
+
+	It("should Watch/Unwatch", func() {
+		err := client.Set("key", "0", 0).Err()
+		Expect(err).NotTo(HaveOccurred())
+
+		perform(C, func(id int) {
+			for i := 0; i < N; i++ {
+				tx, err := client.Watch("key")
+				Expect(err).NotTo(HaveOccurred())
+
+				val, err := tx.Get("key").Result()
+				Expect(err).NotTo(HaveOccurred())
+				Expect(val).NotTo(Equal(redis.Nil))
+
+				num, err := strconv.ParseInt(val, 10, 64)
+				Expect(err).NotTo(HaveOccurred())
+
+				cmds, err := tx.Exec(func() error {
+					tx.Set("key", strconv.FormatInt(num+1, 10), 0)
+					return nil
+				})
+				if err == redis.TxFailedErr {
+					i--
+					continue
+				}
+				Expect(err).NotTo(HaveOccurred())
+				Expect(cmds).To(HaveLen(1))
+				Expect(cmds[0].Err()).NotTo(HaveOccurred())
+
+				err = tx.Close()
+				Expect(err).NotTo(HaveOccurred())
+			}
+		})
+
+		val, err := client.Get("key").Int64()
+		Expect(err).NotTo(HaveOccurred())
+		Expect(val).To(Equal(int64(C * N)))
+	})
+
 })

redis_test.go

@@ -66,11 +66,12 @@ var _ = Describe("Client", func() {
 	})
 
 	It("should close multi without closing the client", func() {
-		multi := client.Multi()
-		Expect(multi.Close()).NotTo(HaveOccurred())
+		tx, err := client.Watch()
+		Expect(err).NotTo(HaveOccurred())
+		Expect(tx.Close()).NotTo(HaveOccurred())
 
-		_, err := multi.Exec(func() error {
-			multi.Ping()
+		_, err = tx.Exec(func() error {
+			tx.Ping()
 			return nil
 		})
 		Expect(err).To(MatchError("redis: client is closed"))
@@ -96,9 +97,10 @@ var _ = Describe("Client", func() {
 	})
 
 	It("should close multi when client is closed", func() {
-		multi := client.Multi()
+		tx, err := client.Watch()
+		Expect(err).NotTo(HaveOccurred())
 		Expect(client.Close()).NotTo(HaveOccurred())
-		Expect(multi.Close()).NotTo(HaveOccurred())
+		Expect(tx.Close()).NotTo(HaveOccurred())
 	})
 
 	It("should close pipeline when client is closed", func() {

tx.go

@@ -9,13 +9,11 @@ import (
 
 var errDiscard = errors.New("redis: Discard can be used only inside Exec")
 
-// Multi implements Redis transactions as described in
+// Tx implements Redis transactions as described in
 // http://redis.io/topics/transactions. It's NOT safe for concurrent use
 // by multiple goroutines, because Exec resets list of watched keys.
 // If you don't need WATCH it is better to use Pipeline.
-//
-// TODO(vmihailenco): rename to Tx and rework API
-type Multi struct {
+type Tx struct {
 	commandable
 
 	base *baseClient
@@ -24,77 +22,78 @@ type Multi struct {
 	closed bool
 }
 
-// Watch creates new transaction and marks the keys to be watched
-// for conditional execution of a transaction.
-func (c *Client) Watch(keys ...string) (*Multi, error) {
-	tx := c.Multi()
-	if err := tx.Watch(keys...).Err(); err != nil {
-		tx.Close()
-		return nil, err
-	}
-	return tx, nil
-}
-
-// Deprecated. Use Watch instead.
-func (c *Client) Multi() *Multi {
-	multi := &Multi{
+func (c *Client) newTx() *Tx {
+	tx := &Tx{
 		base: &baseClient{
 			opt:      c.opt,
 			connPool: pool.NewStickyConnPool(c.connPool.(*pool.ConnPool), true),
 		},
 	}
-	multi.commandable.process = multi.process
-	return multi
+	tx.commandable.process = tx.process
+	return tx
 }
 
-func (c *Multi) process(cmd Cmder) {
-	if c.cmds == nil {
-		c.base.process(cmd)
+// Watch creates new transaction and marks the keys to be watched
+// for conditional execution of a transaction.
+func (c *Client) Watch(keys ...string) (*Tx, error) {
+	tx := c.newTx()
+	if len(keys) > 0 {
+		if err := tx.Watch(keys...).Err(); err != nil {
+			tx.Close()
+			return nil, err
+		}
+	}
+	return tx, nil
+}
+
+func (tx *Tx) process(cmd Cmder) {
+	if tx.cmds == nil {
+		tx.base.process(cmd)
 	} else {
-		c.cmds = append(c.cmds, cmd)
+		tx.cmds = append(tx.cmds, cmd)
 	}
 }
 
-// Close closes the client, releasing any open resources.
-func (c *Multi) Close() error {
-	c.closed = true
-	if err := c.Unwatch().Err(); err != nil {
+// Close closes the transaction, releasing any open resources.
+func (tx *Tx) Close() error {
+	tx.closed = true
+	if err := tx.Unwatch().Err(); err != nil {
 		Logger.Printf("Unwatch failed: %s", err)
 	}
-	return c.base.Close()
+	return tx.base.Close()
 }
 
 // Watch marks the keys to be watched for conditional execution
 // of a transaction.
-func (c *Multi) Watch(keys ...string) *StatusCmd {
+func (tx *Tx) Watch(keys ...string) *StatusCmd {
 	args := make([]interface{}, 1+len(keys))
 	args[0] = "WATCH"
 	for i, key := range keys {
 		args[1+i] = key
 	}
 	cmd := NewStatusCmd(args...)
-	c.Process(cmd)
+	tx.Process(cmd)
 	return cmd
 }
 
 // Unwatch flushes all the previously watched keys for a transaction.
-func (c *Multi) Unwatch(keys ...string) *StatusCmd {
+func (tx *Tx) Unwatch(keys ...string) *StatusCmd {
 	args := make([]interface{}, 1+len(keys))
 	args[0] = "UNWATCH"
 	for i, key := range keys {
 		args[1+i] = key
 	}
 	cmd := NewStatusCmd(args...)
-	c.Process(cmd)
+	tx.Process(cmd)
 	return cmd
 }
 
 // Discard discards queued commands.
-func (c *Multi) Discard() error {
-	if c.cmds == nil {
+func (tx *Tx) Discard() error {
+	if tx.cmds == nil {
 		return errDiscard
 	}
-	c.cmds = c.cmds[:1]
+	tx.cmds = tx.cmds[:1]
 	return nil
 }
 
@@ -107,19 +106,19 @@ func (c *Multi) Discard() error {
 // Exec always returns list of commands. If transaction fails
 // TxFailedErr is returned. Otherwise Exec returns error of the first
 // failed command or nil.
-func (c *Multi) Exec(f func() error) ([]Cmder, error) {
-	if c.closed {
+func (tx *Tx) Exec(f func() error) ([]Cmder, error) {
+	if tx.closed {
 		return nil, pool.ErrClosed
 	}
 
-	c.cmds = []Cmder{NewStatusCmd("MULTI")}
+	tx.cmds = []Cmder{NewStatusCmd("MULTI")}
 	if err := f(); err != nil {
 		return nil, err
 	}
-	c.cmds = append(c.cmds, NewSliceCmd("EXEC"))
+	tx.cmds = append(tx.cmds, NewSliceCmd("EXEC"))
 
-	cmds := c.cmds
-	c.cmds = nil
+	cmds := tx.cmds
+	tx.cmds = nil
 
 	if len(cmds) == 2 {
 		return []Cmder{}, nil
@@ -128,18 +127,18 @@ func (c *Multi) Exec(f func() error) ([]Cmder, error) {
 	// Strip MULTI and EXEC commands.
 	retCmds := cmds[1 : len(cmds)-1]
 
-	cn, err := c.base.conn()
+	cn, err := tx.base.conn()
 	if err != nil {
 		setCmdsErr(retCmds, err)
 		return retCmds, err
 	}
 
-	err = c.execCmds(cn, cmds)
-	c.base.putConn(cn, err, false)
+	err = tx.execCmds(cn, cmds)
+	tx.base.putConn(cn, err, false)
 	return retCmds, err
 }
 
-func (c *Multi) execCmds(cn *pool.Conn, cmds []Cmder) error {
+func (tx *Tx) execCmds(cn *pool.Conn, cmds []Cmder) error {
 	err := writeCmd(cn, cmds...)
 	if err != nil {
 		setCmdsErr(cmds[1:len(cmds)-1], err)

tx_test.go

@@ -10,7 +10,7 @@ import (
 	"gopkg.in/redis.v3"
 )
 
-var _ = Describe("Multi", func() {
+var _ = Describe("Tx", func() {
 	var client *redis.Client
 
 	BeforeEach(func() {
@@ -67,15 +67,16 @@ var _ = Describe("Multi", func() {
 	})
 
 	It("should discard", func() {
-		multi := client.Multi()
+		tx, err := client.Watch("key1", "key2")
+		Expect(err).NotTo(HaveOccurred())
 		defer func() {
-			Expect(multi.Close()).NotTo(HaveOccurred())
+			Expect(tx.Close()).NotTo(HaveOccurred())
 		}()
 
-		cmds, err := multi.Exec(func() error {
-			multi.Set("key1", "hello1", 0)
-			multi.Discard()
-			multi.Set("key2", "hello2", 0)
+		cmds, err := tx.Exec(func() error {
+			tx.Set("key1", "hello1", 0)
+			tx.Discard()
+			tx.Set("key2", "hello2", 0)
 			return nil
 		})
 		Expect(err).NotTo(HaveOccurred())
@@ -91,40 +92,31 @@ var _ = Describe("Multi", func() {
 	})
 
 	It("should exec empty", func() {
-		multi := client.Multi()
+		tx, err := client.Watch()
+		Expect(err).NotTo(HaveOccurred())
 		defer func() {
-			Expect(multi.Close()).NotTo(HaveOccurred())
+			Expect(tx.Close()).NotTo(HaveOccurred())
 		}()
 
-		cmds, err := multi.Exec(func() error { return nil })
+		cmds, err := tx.Exec(func() error { return nil })
 		Expect(err).NotTo(HaveOccurred())
 		Expect(cmds).To(HaveLen(0))
 
-		ping := multi.Ping()
+		ping := tx.Ping()
 		Expect(ping.Err()).NotTo(HaveOccurred())
 		Expect(ping.Val()).To(Equal("PONG"))
 	})
 
-	It("should exec empty queue", func() {
-		multi := client.Multi()
-		defer func() {
-			Expect(multi.Close()).NotTo(HaveOccurred())
-		}()
-
-		cmds, err := multi.Exec(func() error { return nil })
-		Expect(err).NotTo(HaveOccurred())
-		Expect(cmds).To(HaveLen(0))
-	})
-
 	It("should exec bulks", func() {
-		multi := client.Multi()
+		tx, err := client.Watch()
+		Expect(err).NotTo(HaveOccurred())
 		defer func() {
-			Expect(multi.Close()).NotTo(HaveOccurred())
+			Expect(tx.Close()).NotTo(HaveOccurred())
 		}()
 
-		cmds, err := multi.Exec(func() error {
+		cmds, err := tx.Exec(func() error {
 			for i := int64(0); i < 20000; i++ {
-				multi.Incr("key")
+				tx.Incr("key")
 			}
 			return nil
 		})
@@ -148,19 +140,20 @@ var _ = Describe("Multi", func() {
 		err = client.Pool().Put(cn)
 		Expect(err).NotTo(HaveOccurred())
 
-		multi := client.Multi()
+		tx, err := client.Watch()
+		Expect(err).NotTo(HaveOccurred())
 		defer func() {
-			Expect(multi.Close()).NotTo(HaveOccurred())
+			Expect(tx.Close()).NotTo(HaveOccurred())
 		}()
 
-		_, err = multi.Exec(func() error {
-			multi.Ping()
+		_, err = tx.Exec(func() error {
+			tx.Ping()
 			return nil
 		})
 		Expect(err).To(MatchError("bad connection"))
 
-		_, err = multi.Exec(func() error {
-			multi.Ping()
+		_, err = tx.Exec(func() error {
+			tx.Ping()
 			return nil
 		})
 		Expect(err).NotTo(HaveOccurred())