More cluster tests.

cluster.go

@@ -12,6 +12,8 @@ import (
 	"gopkg.in/redis.v5/internal/pool"
 )
 
+var errClusterNoNodes = errors.RedisError("redis: cluster has no nodes")
+
 // ClusterOptions are used to configure a cluster client and should be
 // passed to NewClusterClient.
 type ClusterOptions struct {
@@ -155,14 +157,14 @@ func (c *ClusterClient) cmdInfo(name string) *CommandInfo {
 
 func (c *ClusterClient) getNodes() map[string]*clusterNode {
 	var nodes map[string]*clusterNode
+	c.mu.RLock()
 	if !c.closed {
 		nodes = make(map[string]*clusterNode, len(c.nodes))
-		c.mu.RLock()
 		for addr, node := range c.nodes {
 			nodes[addr] = node
 		}
-		c.mu.RUnlock()
 	}
+	c.mu.RUnlock()
 	return nodes
 }
 
@@ -261,6 +263,9 @@ func (c *ClusterClient) randomNode() (*clusterNode, error) {
 			return nil, pool.ErrClosed
 		}
 
+		if len(addrs) == 0 {
+			return nil, errClusterNoNodes
+		}
 		n := rand.Intn(len(addrs))
 
 		node, err := c.nodeByAddr(addrs[n])

cluster_test.go

@@ -301,6 +301,37 @@ var _ = Describe("ClusterClient", func() {
 			Expect(client.Close()).NotTo(HaveOccurred())
 		})
 
+		It("distributes keys", func() {
+			for i := 0; i < 100; i++ {
+				err := client.Set(fmt.Sprintf("key%d", i), "value", 0).Err()
+				Expect(err).NotTo(HaveOccurred())
+			}
+
+			wanted := []string{"keys=31", "keys=29", "keys=40"}
+			for i, master := range cluster.masters() {
+				Expect(master.Info().Val()).To(ContainSubstring(wanted[i]))
+			}
+		})
+
+		It("distributes keys when using EVAL", func() {
+			script := redis.NewScript(`
+				local r = redis.call('SET', KEYS[1], ARGV[1])
+				return r
+			`)
+
+			var key string
+			for i := 0; i < 100; i++ {
+				key = fmt.Sprintf("key%d", i)
+				err := script.Run(client, []string{key}, "value").Err()
+				Expect(err).NotTo(HaveOccurred())
+			}
+
+			wanted := []string{"keys=31", "keys=29", "keys=40"}
+			for i, master := range cluster.masters() {
+				Expect(master.Info().Val()).To(ContainSubstring(wanted[i]))
+			}
+		})
+
 		It("supports Watch", func() {
 			var incr func(string) error
 
@@ -342,7 +373,8 @@ var _ = Describe("ClusterClient", func() {
 			Expect(n).To(Equal(int64(100)))
 		})
 
-		It("supports pipeline", func() {
+		Describe("pipeline", func() {
+			It("follows redirects", func() {
 				slot := hashtag.Slot("A")
 				Expect(client.SwapSlotNodes(slot)).To(Equal([]string{"127.0.0.1:8224", "127.0.0.1:8221"}))
 
@@ -374,7 +406,7 @@ var _ = Describe("ClusterClient", func() {
 				Expect(cmds[13].(*redis.DurationCmd).Val()).To(BeNumerically("~", 7*time.Hour, time.Second))
 			})
 
-		It("supports pipeline with missing keys", func() {
+			It("works with missing keys", func() {
 				Expect(client.Set("A", "A_value", 0).Err()).NotTo(HaveOccurred())
 				Expect(client.Set("C", "C_value", 0).Err()).NotTo(HaveOccurred())
 
@@ -397,6 +429,7 @@ var _ = Describe("ClusterClient", func() {
 				Expect(c.Err()).NotTo(HaveOccurred())
 				Expect(c.Val()).To(Equal("C_value"))
 			})
+		})
 
 		It("calls fn for every master node", func() {
 			for i := 0; i < 10; i++ {
@@ -451,6 +484,25 @@ var _ = Describe("ClusterClient", func() {
 		describeClusterClient()
 	})
 
+	Describe("ClusterClient without nodes", func() {
+		BeforeEach(func() {
+			client = redis.NewClusterClient(&redis.ClusterOptions{})
+		})
+
+		It("returns an error", func() {
+			err := client.Ping().Err()
+			Expect(err).To(MatchError("redis: cluster has no nodes"))
+		})
+
+		It("pipeline returns an error", func() {
+			_, err := client.Pipelined(func(pipe *redis.Pipeline) error {
+				pipe.Ping()
+				return nil
+			})
+			Expect(err).To(MatchError("redis: cluster has no nodes"))
+		})
+	})
+
 	Describe("ClusterClient without valid nodes", func() {
 		BeforeEach(func() {
 			client = redis.NewClusterClient(&redis.ClusterOptions{
@@ -462,6 +514,14 @@ var _ = Describe("ClusterClient", func() {
 			err := client.Ping().Err()
 			Expect(err).To(MatchError("ERR This instance has cluster support disabled"))
 		})
+
+		It("pipeline returns an error", func() {
+			_, err := client.Pipelined(func(pipe *redis.Pipeline) error {
+				pipe.Ping()
+				return nil
+			})
+			Expect(err).To(MatchError("ERR This instance has cluster support disabled"))
+		})
 	})
 })
 

ring_test.go

@@ -38,7 +38,7 @@ var _ = Describe("Redis Ring", func() {
 		Expect(ring.Close()).NotTo(HaveOccurred())
 	})
 
-	It("uses both shards", func() {
+	It("distributes keys", func() {
 		setRingKeys()
 
 		// Both shards should have some keys now.
@@ -46,6 +46,23 @@ var _ = Describe("Redis Ring", func() {
 		Expect(ringShard2.Info().Val()).To(ContainSubstring("keys=43"))
 	})
 
+	It("distributes keys when using EVAL", func() {
+		script := redis.NewScript(`
+			local r = redis.call('SET', KEYS[1], ARGV[1])
+			return r
+		`)
+
+		var key string
+		for i := 0; i < 100; i++ {
+			key = fmt.Sprintf("key%d", i)
+			err := script.Run(ring, []string{key}, "value").Err()
+			Expect(err).NotTo(HaveOccurred())
+		}
+
+		Expect(ringShard1.Info().Val()).To(ContainSubstring("keys=57"))
+		Expect(ringShard2.Info().Val()).To(ContainSubstring("keys=43"))
+	})
+
 	It("uses single shard when one of the shards is down", func() {
 		// Stop ringShard2.
 		Expect(ringShard2.Close()).NotTo(HaveOccurred())
@@ -89,34 +106,8 @@ var _ = Describe("Redis Ring", func() {
 		Expect(ringShard2.Info().Val()).To(ContainSubstring("keys=100"))
 	})
 
-	It("supports eval key search", func() {
-		script := redis.NewScript(`
-			local r = redis.call('SET', KEYS[1], ARGV[1])
-			return r
-		`)
-
-		var key string
-		for i := 0; i < 100; i++ {
-			key = fmt.Sprintf("key{%d}", i)
-			err := script.Run(ring, []string{key}, "value").Err()
-			Expect(err).NotTo(HaveOccurred())
-		}
-
-		Expect(ringShard1.Info().Val()).To(ContainSubstring("keys=52"))
-		Expect(ringShard2.Info().Val()).To(ContainSubstring("keys=48"))
-	})
-
-	Describe("pipelining", func() {
-		It("returns an error when all shards are down", func() {
-			ring := redis.NewRing(&redis.RingOptions{})
-			_, err := ring.Pipelined(func(pipe *redis.Pipeline) error {
-				pipe.Ping()
-				return nil
-			})
-			Expect(err).To(MatchError("redis: all ring shards are down"))
-		})
-
-		It("uses both shards", func() {
+	Describe("pipeline", func() {
+		It("distributes keys", func() {
 			pipe := ring.Pipeline()
 			for i := 0; i < 100; i++ {
 				err := pipe.Set(fmt.Sprintf("key%d", i), "value", 0).Err()
@@ -175,3 +166,28 @@ var _ = Describe("Redis Ring", func() {
 		})
 	})
 })
+
+var _ = Describe("empty Redis Ring", func() {
+	var ring *redis.Ring
+
+	BeforeEach(func() {
+		ring = redis.NewRing(&redis.RingOptions{})
+	})
+
+	AfterEach(func() {
+		Expect(ring.Close()).NotTo(HaveOccurred())
+	})
+
+	It("returns an error", func() {
+		err := ring.Ping().Err()
+		Expect(err).To(MatchError("redis: all ring shards are down"))
+	})
+
+	It("pipeline returns an error", func() {
+		_, err := ring.Pipelined(func(pipe *redis.Pipeline) error {
+			pipe.Ping()
+			return nil
+		})
+		Expect(err).To(MatchError("redis: all ring shards are down"))
+	})
+})