# Simple AmazonSQS Transport usage


This sample shows the basic usage of SQS as a transport for NServiceBus. The application sends messages between two endpoints, via the SQS transport, and writes a message to the console when a message is received.



## AWS setup

### Security and access configuration

Add the [AWS Access Key ID and AWS Secret Access Key](https://docs.aws.amazon.com/general/latest/gr/aws-sec-cred-types.html#access-keys-and-secret-access-keys) to the following environment variables:

* Access Key ID in `AWS_ACCESS_KEY_ID`
* Secret Access Key in `AWS_SECRET_ACCESS_KEY`
* Default Region in `AWS_REGION`

See also [AWS Account Identifiers](https://docs.aws.amazon.com/general/latest/gr/acct-identifiers.html), [Managing Access Keys for an AWS Account](https://docs.aws.amazon.com/general/latest/gr/managing-aws-access-keys.html), and [IAM Security Credentials](https://console.aws.amazon.com/iam/home#/security_credential).

See also [AWS Regions](https://docs.aws.amazon.com/general/latest/gr/rande.html) for a list of available regions.

### SQS

Several [Amazon SQS](https://aws.amazon.com/sqs/) queues are required to run this sample. These will be created at start-up via the [installer mechanism](/nservicebus/operations/installers.md) of NServiceBus. The queues can be seen in the [SQS management UI](https://console.aws.amazon.com/sqs/home).

* `Samples-Sqs-SimpleReceiver`: Queue used by the Receiver endpoint to receive and process incoming messages.
* `Samples-Sqs-SimpleReceiver-delay.fifo`: Queue used by the Receiver endpoint for [delayed retries](/nservicebus/recoverability/index.md#delayed-retries).
* `Samples-Sqs-SimpleSender`: Queue used by the sender endpoint to dispatch commands and publish events.
* `Samples-Sqs-SimpleSender-delay.fifo`: Queue used by the Sender endpoint for [delayed retries](/nservicebus/recoverability/index.md#delayed-retries).

### S3

An [Amazon S3](https://console.aws.amazon.com/s3) bucket is required to leverage the [S3 bucket for large messages](/transports/sqs/configuration-options.md#offload-large-messages-to-s3) feature of the SQS transport. [Create an S3 bucket](https://docs.aws.amazon.com/AmazonS3/latest/UG/CreatingaBucket.html) and replace the `bucketname` in the sample startup with the name of the created bucket.

## Endpoint configuration

Configure the endpoints to use the [SQS transport](/transports/sqs/index.md).

<!-- snippet: ConfigureEndpoint -->

```cs
var endpointConfiguration = new EndpointConfiguration("Samples.Sqs.SimpleSender");
endpointConfiguration.UseSerialization<SystemJsonSerializer>();

var transport = new SqsTransport
{
    S3 = new S3Settings("bucketname", "my/key/prefix")
};

var routing = endpointConfiguration.UseTransport(transport);
```

<!-- endsnippet -->

## Run the sample

Start the endpoints. Two console applications will be started, a receiver endpoint can send commands or publish events to the subscriber endpoint. In addition, large message bodies can be sent using S3 as the storage for the message payload.

### View a message in transit

To view a message in transit, stop the receiver endpoint while sending/publishing further messages from the sender endpoint. The messages will be written to SQS but not dequeued. The message can now be viewed in the [SQS management UI](https://console.aws.amazon.com/sqs/home).

![](message.png "width=300")

The large message contents can be viewed in the [S3 management UI](https://console.aws.amazon.com/s3).

![](s3bucket.png "width=300")

See also [Receiving and Deleting a Message from an Amazon SQS Queue](https://docs.aws.amazon.com/AWSSimpleQueueService/latest/SQSDeveloperGuide/sqs-receive-delete-message.html).