Add input flag to change API base path

Author: kirbyquerby

cmd/cloud_sql_proxy/cloud_sql_proxy.go

@@ -84,6 +84,9 @@ You may set the GOOGLE_APPLICATION_CREDENTIALS environment variable for the same
 
 	// Set to non-default value when gcloud execution failed.
 	gcloudStatus gcloudStatusCode
+
+	// Setting to choose what API to connect to
+	host = flag.String("host", "https://www.googleapis.com/sql/v1beta4/", "When set, the proxy uses this host as the base API path.")
 )
 
 type gcloudStatusCode int
@@ -98,7 +101,6 @@ const (
 const (
 	minimumRefreshCfgThrottle = time.Second
 
-	host = "https://www.googleapis.com/sql/v1beta4/"
 	port = 3307
 )
 
@@ -493,7 +495,7 @@ func main() {
 		Port:           port,
 		MaxConnections: *maxConnections,
 		Certs: certs.NewCertSourceOpts(client, certs.RemoteOpts{
-			APIBasePath:  host,
+			APIBasePath:  *host,
 			IgnoreRegion: !*checkRegion,
 			UserAgent:    userAgentFromVersionString(),
 		}),

cmd/cloud_sql_proxy/proxy.go

@@ -238,6 +238,7 @@ func parseInstanceConfig(dir, instance string, cl *http.Client) (instanceConfig,
 		}
 	} else {
 		sql, err := sqladmin.New(cl)
+		sql.BasePath = *host
 		if err != nil {
 			return instanceConfig{}, err
 		}