SQS vs SNS

SQS vs SNS

using Amazon.Auth.AccessControlPolicy;
using Amazon.Auth.AccessControlPolicy.ActionIdentifiers;
using Amazon.SimpleNotificationService;
using Amazon.SQS;
using Amazon.SQS.Model;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace AwsTest
{
    class Program
    {
        static void Main(string[] args)
        {
            var sqs = new AmazonSQSClient();
            var sns = new AmazonSimpleNotificationServiceClient();

            var queueUrl = sqs.CreateQueue("testQueue8").QueueUrl;
            var queueArn = sqs.GetQueueAttributes(queueUrl, new List<string> { "QueueArn" }).QueueARN;

            var topicArn = sns.CreateTopic("testTopic8").TopicArn;
            var subscriptionArn = sns.Subscribe(topicArn, "sqs", queueArn).SubscriptionArn;

            var policy = new Policy()
            {
                Statements = new List<Statement>() {
                    new Statement(Statement.StatementEffect.Allow) {
                        Principals = new List<Principal>() { Principal.AllUsers},
                        Actions = new List<ActionIdentifier>() { SQSActionIdentifiers.SendMessage },
                        Conditions = new List<Condition>
                        {
                            ConditionFactory.NewCondition(ConditionFactory.ArnComparisonType.ArnEquals, "aws:SourceArn", topicArn)
                        }
                    }
                }
            };

            var request = new SetQueueAttributesRequest()
            {
                QueueUrl = queueUrl,
                Attributes = new Dictionary<string, string>
                {
                    { QueueAttributeName.Policy, policy.ToJson()}
                }
            };
            sqs.SetQueueAttributes(request);

            sns.Publish(topicArn, "this is a test");
            Console.WriteLine($"{sqs.ReceiveMessage(queueUrl).Messages.Count}");
            Console.WriteLine("End");
            Console.ReadKey(true);
        }

    }
}