From ce9cfe9417774ec4e2a4e65dab39c261f239d6b6 Mon Sep 17 00:00:00 2001
From: Vladimir Mihailenco <vladimir.webdev@gmail.com>
Date: Sun, 22 Jul 2018 09:46:29 +0300
Subject: [PATCH] Add MemoryUsage

---
 commands.go      | 20 +++++++++++++++++---
 commands_test.go | 31 ++++++++++++++++++++++++-------
 2 files changed, 41 insertions(+), 10 deletions(-)

diff --git a/commands.go b/commands.go
index 7b6c65df..763c8370 100644
--- a/commands.go
+++ b/commands.go
@@ -62,6 +62,7 @@ type Cmdable interface {
 	TxPipelined(fn func(Pipeliner) error) ([]Cmder, error)
 	TxPipeline() Pipeliner
 
+	Command() *CommandsInfoCmd
 	ClientGetName() *StringCmd
 	Echo(message interface{}) *StringCmd
 	Ping() *StatusCmd
@@ -275,9 +276,9 @@ type Cmdable interface {
 	GeoRadiusByMemberRO(key, member string, query *GeoRadiusQuery) *GeoLocationCmd
 	GeoDist(key string, member1, member2, unit string) *FloatCmd
 	GeoHash(key string, members ...string) *StringSliceCmd
-	Command() *CommandsInfoCmd
 	ReadOnly() *StatusCmd
 	ReadWrite() *StatusCmd
+	MemoryUsage(key string, samples ...int) *IntCmd
 }
 
 type StatefulCmdable interface {
@@ -355,6 +356,12 @@ func (c *statefulCmdable) SwapDB(index1, index2 int) *StatusCmd {
 
 //------------------------------------------------------------------------------
 
+func (c *cmdable) Command() *CommandsInfoCmd {
+	cmd := NewCommandsInfoCmd("command")
+	c.process(cmd)
+	return cmd
+}
+
 func (c *cmdable) Del(keys ...string) *IntCmd {
 	args := make([]interface{}, 1+len(keys))
 	args[0] = "del"
@@ -2301,8 +2308,15 @@ func (c *cmdable) GeoPos(key string, members ...string) *GeoPosCmd {
 
 //------------------------------------------------------------------------------
 
-func (c *cmdable) Command() *CommandsInfoCmd {
-	cmd := NewCommandsInfoCmd("command")
+func (c *cmdable) MemoryUsage(key string, samples ...int) *IntCmd {
+	args := []interface{}{"memory", "usage", key}
+	if len(samples) > 0 {
+		if len(samples) != 1 {
+			panic("MemoryUsage expects single sample count")
+		}
+		args = append(args, "SAMPLES", samples[0])
+	}
+	cmd := NewIntCmd(args...)
 	c.process(cmd)
 	return cmd
 }
diff --git a/commands_test.go b/commands_test.go
index 896aee90..6bec8116 100644
--- a/commands_test.go
+++ b/commands_test.go
@@ -244,14 +244,31 @@ var _ = Describe("Commands", func() {
 	Describe("debugging", func() {
 
 		It("should DebugObject", func() {
-			debug := client.DebugObject("foo")
-			Expect(debug.Err()).To(HaveOccurred())
-			Expect(debug.Err().Error()).To(Equal("ERR no such key"))
+			err := client.DebugObject("foo").Err()
+			Expect(err).To(MatchError("ERR no such key"))
 
-			client.Set("foo", "bar", 0)
-			debug = client.DebugObject("foo")
-			Expect(debug.Err()).NotTo(HaveOccurred())
-			Expect(debug.Val()).To(ContainSubstring(`serializedlength:4`))
+			err = client.Set("foo", "bar", 0).Err()
+			Expect(err).NotTo(HaveOccurred())
+
+			s, err := client.DebugObject("foo").Result()
+			Expect(err).NotTo(HaveOccurred())
+			Expect(s).To(ContainSubstring("serializedlength:4"))
+		})
+
+		It("should MemoryUsage", func() {
+			err := client.MemoryUsage("foo").Err()
+			Expect(err).To(Equal(redis.Nil))
+
+			err = client.Set("foo", "bar", 0).Err()
+			Expect(err).NotTo(HaveOccurred())
+
+			n, err := client.MemoryUsage("foo").Result()
+			Expect(err).NotTo(HaveOccurred())
+			Expect(n).To(Equal(int64(52)))
+
+			n, err = client.MemoryUsage("foo", 0).Result()
+			Expect(err).NotTo(HaveOccurred())
+			Expect(n).To(Equal(int64(52)))
 		})
 
 	})