Merge pull request #90 from go-redis/fix/pool-waiting-for-connection

Fix pool waiting for connection that was removed.

cluster.go

@@ -256,29 +256,13 @@ type ClusterOptions struct {
 	// giving up. Default: 16
 	MaxRedirects int
 
-	// The maximum number of TCP sockets per connection. Default: 5
+	// Following options are copied from `redis.Options`.
 	PoolSize                                                         int
-
+	DialTimeout, ReadTimeout, WriteTimeout, PoolTimeout, IdleTimeout time.Duration
-	// Timeout settings
-	DialTimeout, ReadTimeout, WriteTimeout, IdleTimeout time.Duration
-}
-
-func (opt *ClusterOptions) getPoolSize() int {
-	if opt.PoolSize < 1 {
-		return 5
-	}
-	return opt.PoolSize
-}
-
-func (opt *ClusterOptions) getDialTimeout() time.Duration {
-	if opt.DialTimeout == 0 {
-		return 5 * time.Second
-	}
-	return opt.DialTimeout
 }
 
 func (opt *ClusterOptions) getMaxRedirects() int {
-	if opt.MaxRedirects < 1 {
+	if opt.MaxRedirects == 0 {
 		return 16
 	}
 	return opt.MaxRedirects
@@ -289,11 +273,12 @@ func (opt *ClusterOptions) clientOptions() *Options {
 		DB:       0,
 		Password: opt.Password,
 
-		DialTimeout:  opt.getDialTimeout(),
+		DialTimeout:  opt.DialTimeout,
 		ReadTimeout:  opt.ReadTimeout,
 		WriteTimeout: opt.WriteTimeout,
 
-		PoolSize:    opt.getPoolSize(),
+		PoolSize:    opt.PoolSize,
+		PoolTimeout: opt.PoolTimeout,
 		IdleTimeout: opt.IdleTimeout,
 	}
 }

pool.go

@@ -133,7 +133,7 @@ func (p *connPool) First() *conn {
 		select {
 		case cn := <-p.freeConns:
 			if cn.isIdle(p.opt.IdleTimeout) {
-				p.remove(cn)
+				p.Remove(cn)
 				continue
 			}
 			return cn
@@ -151,7 +151,7 @@ func (p *connPool) wait(timeout time.Duration) *conn {
 		select {
 		case cn := <-p.freeConns:
 			if cn.isIdle(p.opt.IdleTimeout) {
-				p.remove(cn)
+				p.Remove(cn)
 				continue
 			}
 			return cn
@@ -215,10 +215,6 @@ func (p *connPool) Put(cn *conn) error {
 		log.Printf("redis: connection has unread data: %q", b)
 		return p.Remove(cn)
 	}
-
-	if p.isClosed() {
-		return errClosed
-	}
 	if p.opt.IdleTimeout > 0 {
 		cn.usedAt = time.Now()
 	}
@@ -228,13 +224,18 @@ func (p *connPool) Put(cn *conn) error {
 
 func (p *connPool) Remove(cn *conn) error {
 	if p.isClosed() {
-		return nil
+		atomic.AddInt32(&p.size, -1)
-	}
+		return cn.Close()
-	return p.remove(cn)
 	}
 
-func (p *connPool) remove(cn *conn) error {
+	// Replace existing connection with new one and unblock `wait`.
+	newcn, err := p.new()
+	if err != nil {
 		atomic.AddInt32(&p.size, -1)
+	} else {
+		p.Put(newcn)
+	}
+
 	return cn.Close()
 }
 
@@ -259,7 +260,7 @@ func (p *connPool) Close() (retErr error) {
 		if cn == nil {
 			break
 		}
-		if err := p.remove(cn); err != nil {
+		if err := p.Remove(cn); err != nil {
 			retErr = err
 		}
 	}

pool_test.go

@@ -7,11 +7,13 @@ import (
 
 	. "github.com/onsi/ginkgo"
 	. "github.com/onsi/gomega"
+
 	"gopkg.in/redis.v2"
 )
 
 var _ = Describe("Pool", func() {
 	var client *redis.Client
+
 	var perform = func(n int, cb func()) {
 		wg := &sync.WaitGroup{}
 		for i := 0; i < n; i++ {
@@ -27,13 +29,14 @@ var _ = Describe("Pool", func() {
 	}
 
 	BeforeEach(func() {
-		client = redis.NewTCPClient(&redis.Options{
+		client = redis.NewClient(&redis.Options{
 			Addr:     redisAddr,
+			PoolSize: 10,
 		})
 	})
 
 	AfterEach(func() {
-		client.FlushDb()
+		Expect(client.FlushDb().Err()).NotTo(HaveOccurred())
 		Expect(client.Close()).NotTo(HaveOccurred())
 	})
 
@@ -98,8 +101,8 @@ var _ = Describe("Pool", func() {
 		})
 
 		pool := client.Pool()
-		Expect(pool.Size()).To(Equal(0))
+		Expect(pool.Size()).To(Equal(10))
-		Expect(pool.Len()).To(Equal(0))
+		Expect(pool.Len()).To(Equal(10))
 	})
 
 	It("should remove broken connections", func() {
@@ -133,6 +136,48 @@ var _ = Describe("Pool", func() {
 		Expect(pool.Len()).To(Equal(1))
 	})
 
+	It("should unblock client when connection is removed", func() {
+		pool := client.Pool()
+
+		// Reserve one connection.
+		cn, _, err := client.Pool().Get()
+		Expect(err).NotTo(HaveOccurred())
+
+		// Reserve the rest of connections.
+		for i := 0; i < 9; i++ {
+			_, _, err := client.Pool().Get()
+			Expect(err).NotTo(HaveOccurred())
+		}
+
+		var ping *redis.StatusCmd
+		started := make(chan bool, 1)
+		done := make(chan bool, 1)
+		go func() {
+			started <- true
+			ping = client.Ping()
+			done <- true
+		}()
+		<-started
+
+		// Check that Ping is blocked.
+		select {
+		case <-done:
+			panic("Ping is not blocked")
+		default:
+			// ok
+		}
+
+		Expect(pool.Remove(cn)).NotTo(HaveOccurred())
+
+		// Check that Ping is unblocked.
+		select {
+		case <-done:
+			// ok
+		case <-time.After(time.Second):
+			panic("Ping is not unblocked")
+		}
+		Expect(ping.Err()).NotTo(HaveOccurred())
+	})
 })
 
 func BenchmarkPool(b *testing.B) {

redis.go

@@ -160,10 +160,8 @@ type Options struct {
 	// The maximum number of socket connections.
 	// Default: 10
 	PoolSize int
-	// If all socket connections is the pool are busy, the pool will wait
+	// PoolTimeout specifies amount of time client waits for a free
-	// this amount of time for a conection to become available, before
+	// connection in the pool. Default timeout is 1s.
-	// returning an error.
-	// Default: 5s
 	PoolTimeout time.Duration
 	// Evict connections from the pool after they have been idle for longer
 	// than specified in this option.
@@ -194,7 +192,7 @@ func (opt *Options) getDialTimeout() time.Duration {
 
 func (opt *Options) getPoolTimeout() time.Duration {
 	if opt.PoolTimeout == 0 {
-		return 5 * time.Second
+		return 1 * time.Second
 	}
 	return opt.PoolTimeout
 }

redis_test.go

@@ -92,7 +92,7 @@ var _ = Describe("Client", func() {
 	It("should support idle-timeouts", func() {
 		idle := redis.NewTCPClient(&redis.Options{
 			Addr:        redisAddr,
-			IdleTimeout: time.Nanosecond,
+			IdleTimeout: 100 * time.Microsecond,
 		})
 		defer idle.Close()