OASIS-25999 Retry on 503 error - example (#638)

Author: jwierzbo

Diff for: v2/examples/example_client_retry_on_503_test.go

@@ -0,0 +1,57 @@
+//
+// DISCLAIMER
+//
+// Copyright 2024 ArangoDB GmbH, Cologne, Germany
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+// Copyright holder is ArangoDB GmbH, Cologne, Germany
+//
+
+package examples
+
+import (
+	"context"
+	"log"
+
+	"github.com/arangodb/go-driver/v2/arangodb"
+	"github.com/arangodb/go-driver/v2/connection"
+)
+
+// Example503Retry shows how to create a client with round-robin endpoint list and retry on 503
+func Example503Retry() {
+	// Create an HTTP connection to the database
+	endpoint := connection.NewRoundRobinEndpoints([]string{"http://localhost:8529"})
+	conn := connection.NewHttp2Connection(connection.DefaultHTTP2ConfigurationWrapper(endpoint, true))
+
+	// Add authentication
+	auth := connection.NewBasicAuth("root", "")
+	err := conn.SetAuthentication(auth)
+	if err != nil {
+		log.Fatalf("Failed to set authentication: %v", err)
+	}
+
+	// Add retry on 503
+	retries := 5
+	conn = connection.RetryOn503(conn, retries)
+
+	// Create a client
+	client := arangodb.NewClient(conn)
+
+	// Ask the version of the server
+	versionInfo, err := client.Version(context.Background())
+	if err != nil {
+		log.Printf("Failed to get version info: %v", err)
+	}
+	log.Printf("Database has version '%s' and license '%s'\n", versionInfo.Version, versionInfo.License)
+}