Add redis host and port parameter to the scaler with tests (#719)

Signed-off-by: Ivan Gualandri <ivan.gualandri@gmail.com>

pkg/scalers/redis_scaler.go

@@ -22,6 +22,8 @@ const (
 	defaultRedisPassword    = ""
 	defaultDbIdx            = 0
 	defaultEnableTLS        = false
+	defaultHost             = ""
+	defaultPort             = ""
 )
 
 type redisScaler struct {
@@ -33,6 +35,8 @@ type redisMetadata struct {
 	listName         string
 	address          string
 	password         string
+	host             string
+	port             string
 	databaseIndex    int
 	enableTLS        bool
 }
@@ -70,14 +74,38 @@ func parseRedisMetadata(metadata, resolvedEnv, authParams map[string]string) (*r
 	}
 
 	address := defaultRedisAddress
+	host := defaultHost
+	port := defaultPort
 	if val, ok := metadata["address"]; ok && val != "" {
 		address = val
+	} else {
+		if val, ok := metadata["host"]; ok && val != "" {
+			host = val
+		} else {
+			return nil, fmt.Errorf("no address or host given. address should be in the format of host:port or you should set the host/port values")
+		}
+		if val, ok := metadata["port"]; ok && val != "" {
+			port = val
+		} else {
+			return nil, fmt.Errorf("no address or port given. address should be in the format of host:port or you should set the host/port values")
+		}
 	}
 
 	if val, ok := resolvedEnv[address]; ok {
 		meta.address = val
 	} else {
-		return nil, fmt.Errorf("no address given. Address should be in the format of host:port")
+		if val, ok := resolvedEnv[host]; ok {
+			meta.host = val
+		} else {
+			return nil, fmt.Errorf("no address given or host given. Address should be in the format of host:port or you should provide both host and port")
+		}
+
+		if val, ok := resolvedEnv[port]; ok {
+			meta.port = val
+		} else {
+			return nil, fmt.Errorf("no address or port given. Address should be in the format of host:port or you should provide both host and port")
+		}
+		meta.address = fmt.Sprintf("%s:%s", meta.host, meta.port)
 	}
 
 	meta.password = defaultRedisPassword

pkg/scalers/redis_scaler_test.go

@@ -6,6 +6,7 @@ import (
 
 var testRedisResolvedEnv = map[string]string{
 	"REDIS_HOST":     "none",
+	"REDIS_PORT":     "6379",
 	"REDIS_PASSWORD": "none",
 }
 
@@ -20,6 +21,12 @@ var testRedisMetadata = []parseRedisMetadataTestData{
 	{map[string]string{}, true, map[string]string{}},
 	// properly formed listName
 	{map[string]string{"listName": "mylist", "listLength": "10", "address": "REDIS_HOST", "password": "REDIS_PASSWORD"}, false, map[string]string{}},
+	// properly formed hostPort
+	{map[string]string{"listName": "mylist", "listLength": "10", "host": "REDIS_HOST", "port": "REDIS_PORT", "password": "REDIS_PASSWORD"}, false, map[string]string{}},
+	// properly formed hostPort
+	{map[string]string{"listName": "mylist", "listLength": "10", "address": "REDIS_HOST", "host": "REDIS_HOST", "port": "REDIS_PORT", "password": "REDIS_PASSWORD"}, false, map[string]string{}},
+	// improperly formed hostPort
+	{map[string]string{"listName": "mylist", "listLength": "10", "host": "REDIS_HOST", "password": "REDIS_PASSWORD"}, true, map[string]string{}},
 	// properly formed listName, empty address
 	{map[string]string{"listName": "mylist", "listLength": "10", "address": "", "password": ""}, true, map[string]string{}},
 	// improperly formed listLength