Go: ZDiff command added

Signed-off-by: Prateek Kumar <prateek.kumar@improving.com>

go/api/base_client.go

@@ -7011,3 +7011,71 @@ func (client *baseClient) Time() ([]string, error) {
 	}
 	return handleStringArrayResponse(result)
 }
+
+// Returns the difference between the first sorted set and all the successive sorted sets.<br>
+// To get the elements with their scores, see `ZDiffWithScores`
+// When in cluster mode, all `keys` must map to the same hash slot.
+// Valkey 6.2 and above.
+//
+// See [valkey.io] for details.
+//
+// Parameters:
+//
+//	keys -  The keys of the sorted sets.
+//
+// Return value:
+//
+//	An array of elements representing the difference between the sorted sets.
+//	If the first `key` does not exist, it is treated as an empty sorted set, and the
+//	command returns an empty array.
+//
+// Example:
+//
+//	zAddResult1, err := client.ZAdd(key1, membersScores1)
+//	zAddResult2, err := client.ZAdd(key2, membersScores2)
+//	zDiffResult, err := client.ZDiff([]string{key1, key2})
+//	fmt.Println(zDiffResult) // Output: {"one", "three"}
+//
+// [valkey.io]: https://valkey.io/commands/zdiff/
+func (client *baseClient) ZDiff(keys []string) ([]string, error) {
+	args := append([]string{}, strconv.Itoa(len(keys)))
+	result, err := client.executeCommand(C.ZDiff, append(args, keys...))
+	if err != nil {
+		return nil, err
+	}
+	return handleStringArrayResponse(result)
+}
+
+// Returns the difference between the first sorted set and all the successive sorted sets.
+// When in cluster mode, all `keys` must map to the same hash slot.
+// Valkey 6.2 and above.
+//
+// See [valkey.io] for details.
+//
+// Parameters:
+//
+//	keys -  The keys of the sorted sets.
+//
+// Return value:
+//
+//	A `Map` of elements and their scores representing the difference between the sorted sets.
+//	If the first `key` does not exist, it is treated as an empty sorted set, and the
+//	command returns an empty `Map`.
+//
+// Example:
+//
+//	zAddResult1, err := client.ZAdd(key1, membersScores1)
+//	zAddResult2, err := client.ZAdd(key2, membersScores2)
+//	zDiffResultWithScores, err := client.ZDiffWithScores([]string{key1, key2})
+//	fmt.Println(zDiffResultWithScores) // Output: {"one": 1.0, "three": 3.0}
+//
+// [valkey.io]: https://valkey.io/commands/zdiff/
+func (client *baseClient) ZDiffWithScores(keys []string) (map[string]float64, error) {
+	args := append([]string{}, strconv.Itoa(len(keys)))
+	args = append(args, keys...)
+	result, err := client.executeCommand(C.ZDiff, append(args, options.WithScores))
+	if err != nil {
+		return nil, err
+	}
+	return handleStringDoubleMapResponse(result)
+}

go/api/options/constants.go

@@ -9,6 +9,7 @@ const (
 	WithScore    string = "WITHSCORE"  // Valkey API keyword for the with score option for zrank and zrevrank commands.
 	NoScores     string = "NOSCORES"   // Valkey API keyword for the no scores option for zscan command.
 	WithValues   string = "WITHVALUES" // Valkey API keyword to query hash values along their names in `HRANDFIELD`.
+	WithScores   string = "WITHSCORES" // Valkey API keyword for the with scores option for zdiff command.
 )
 
 type InfBoundary string

go/api/sorted_set_commands.go

@@ -70,4 +70,8 @@ type SortedSetCommands interface {
 	ZRemRangeByRank(key string, start int64, stop int64) (int64, error)
 
 	ZRemRangeByScore(key string, rangeQuery options.RangeByScore) (int64, error)
+
+	ZDiff(keys []string) ([]string, error)
+
+	ZDiffWithScores(keys []string) (map[string]float64, error)
 }

go/integTest/shared_commands_test.go

@@ -7694,3 +7694,73 @@ func (suite *GlideTestSuite) TestBitFieldRO_MultipleGets() {
 		assert.Equal(suite.T(), []int64{value1, value2}, []int64{getRO[0].Value(), getRO[1].Value()})
 	})
 }
+
+func (suite *GlideTestSuite) TestZDiff() {
+	suite.runWithDefaultClients(func(client api.BaseClient) {
+		suite.SkipIfServerVersionLowerThanBy("6.2.0")
+		t := suite.T()
+		key1 := "{testKey}:1-" + uuid.NewString()
+		key2 := "{testKey}:2-" + uuid.NewString()
+		key3 := "{testKey}:3-" + uuid.NewString()
+		nonExistentKey := "{testKey}:4-" + uuid.NewString()
+
+		membersScores1 := map[string]float64{
+			"one":   1.0,
+			"two":   2.0,
+			"three": 3.0,
+		}
+
+		membersScores2 := map[string]float64{
+			"two": 2.0,
+		}
+
+		membersScores3 := map[string]float64{
+			"one":   1.0,
+			"two":   2.0,
+			"three": 3.0,
+			"four":  4.0,
+		}
+
+		zAddResult1, err := client.ZAdd(key1, membersScores1)
+		assert.NoError(t, err)
+		assert.Equal(t, int64(3), zAddResult1)
+		zAddResult2, err := client.ZAdd(key2, membersScores2)
+		assert.NoError(t, err)
+		assert.Equal(t, int64(1), zAddResult2)
+		zAddResult3, err := client.ZAdd(key3, membersScores3)
+		assert.NoError(t, err)
+		assert.Equal(t, int64(4), zAddResult3)
+
+		zDiffResult, err := client.ZDiff([]string{key1, key2})
+		assert.NoError(t, err)
+		assert.Equal(t, []string{"one", "three"}, zDiffResult)
+		zDiffResult, err = client.ZDiff([]string{key1, key3})
+		assert.NoError(t, err)
+		assert.Equal(t, []string{}, zDiffResult)
+		zDiffResult, err = client.ZDiff([]string{nonExistentKey, key3})
+		assert.NoError(t, err)
+		assert.Equal(t, []string{}, zDiffResult)
+
+		zDiffResultWithScores, err := client.ZDiffWithScores([]string{key1, key2})
+		assert.NoError(t, err)
+		assert.Equal(t, map[string]float64{"one": 1.0, "three": 3.0}, zDiffResultWithScores)
+		zDiffResultWithScores, err = client.ZDiffWithScores([]string{key1, key3})
+		assert.NoError(t, err)
+		assert.Equal(t, map[string]float64{}, zDiffResultWithScores)
+		zDiffResultWithScores, err = client.ZDiffWithScores([]string{nonExistentKey, key3})
+		assert.NoError(t, err)
+		assert.Equal(t, map[string]float64{}, zDiffResultWithScores)
+
+		// Key exists, but it is not a set
+		setResult, err := client.Set(nonExistentKey, "bar")
+		assert.Equal(t, setResult, "OK")
+
+		zDiffResult, err = client.ZDiff([]string{nonExistentKey, key2})
+		assert.NotNil(t, err)
+		assert.IsType(t, &errors.RequestError{}, err)
+
+		zDiffResultWithScores, err = client.ZDiffWithScores([]string{nonExistentKey, key2})
+		assert.NotNil(t, err)
+		assert.IsType(t, &errors.RequestError{}, err)
+	})
+}