csharp/examples/SimpleConsumerExample.cs

/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You 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.
 */

using System;
using System.Collections.Generic;
using System.Threading.Tasks;
using Microsoft.Extensions.Logging;
using Org.Apache.Rocketmq;

namespace examples
{
    internal static class SimpleConsumerExample
    {
        private static readonly ILogger Logger = MqLogManager.CreateLogger(typeof(SimpleConsumerExample).FullName);

        internal static async Task QuickStart()
        {
            // Enable the switch if you use .NET Core 3.1 and want to disable TLS/SSL.
            // AppContext.SetSwitch("System.Net.Http.SocketsHttpHandler.Http2UnencryptedSupport", true);
            const string accessKey = "yourAccessKey";
            const string secretKey = "yourSecretKey";

            // Credential provider is optional for client configuration.
            var credentialsProvider = new StaticSessionCredentialsProvider(accessKey, secretKey);
            const string endpoints = "foobar.com:8080";
            var clientConfig = new ClientConfig.Builder()
                .SetEndpoints(endpoints)
                .SetCredentialsProvider(credentialsProvider)
                .Build();

            // Add your subscriptions.
            const string consumerGroup = "yourConsumerGroup";
            const string topic = "yourTopic";
            var subscription = new Dictionary<string, FilterExpression>
                { { topic, new FilterExpression("*") } };
            // In most case, you don't need to create too many consumers, single pattern is recommended.
            var simpleConsumer = await new SimpleConsumer.Builder()
                .SetClientConfig(clientConfig)
                .SetConsumerGroup(consumerGroup)
                .SetAwaitDuration(TimeSpan.FromSeconds(15))
                .SetSubscriptionExpression(subscription)
                .Build();

            while (true)
            {
                var messageViews = await simpleConsumer.Receive(16, TimeSpan.FromSeconds(15));
                foreach (var message in messageViews)
                {
                    Logger.LogInformation(
                        $"Received a message, topic={message.Topic}, message-id={message.MessageId}, body-size={message.Body.Length}");
                    await simpleConsumer.Ack(message);
                    Logger.LogInformation($"Message is acknowledged successfully, message-id={message.MessageId}");
                    // await simpleConsumer.ChangeInvisibleDuration(message, TimeSpan.FromSeconds(15));
                    // Logger.LogInformation($"Changing message invisible duration successfully, message=id={message.MessageId}");
                }
            }
            // Close the simple consumer if you don't need it anymore.
            // await simpleConsumer.DisposeAsync();
        }
    }
}