# Send messages to an Amazon SQS queue with Step Functions
<a name="connect-sqs"></a>

You can to send messages to an Amazon SQS queue using the following Amazon SQS API actions and example `Task` state code for Step Functions workflows.

To learn about integrating with AWS services in Step Functions, see [Integrating services](integrate-services.md) and [Passing parameters to a service API in Step Functions](connect-parameters.md).

To learn more about receiving messages in Amazon SQS, see [Receive and Delete Your Message](https://docs.aws.amazon.com/AWSSimpleQueueService/latest/SQSDeveloperGuide/step-receive-delete-message.html) in the *Amazon Simple Queue Service Developer Guide*.

The following sample includes a `Task` state (JSONata) that sends an Amazon Simple Queue Service (Amazon SQS) message with optional **MessageAttributes**:

```
{
 "StartAt": "Send to SQS",
 "States": {
   "Send to SQS": {
     "Type": "Task",
     "Resource": "arn:aws:states:::sqs:sendMessage",
     "Arguments": {
       "QueueUrl": "https://sqs.us-east-1.amazonaws.com/account-id/myQueue",
       "MessageBody": "{% $states.input.message %}",
       "MessageAttributes": {
         "my_attribute_no_1": {
           "DataType": "String",
           "StringValue": "attribute1"
         },
         "my_attribute_no_2": {
           "DataType": "String",
           "StringValue": "attribute2"
         }
       }
     },
     "End": true
    }
  }
}
```

The following state machine includes a `Task` state that publishes to an Amazon SQS queue, and then waits for the task token to be returned. See [Wait for a Callback with Task Token](connect-to-resource.md#connect-wait-token).

```
{  
   "StartAt":"Send message to SQS",
   "States":{  
      "Send message to SQS":{  
         "Type":"Task",
         "Resource":"arn:aws:states:::sqs:sendMessage.waitForTaskToken",
         "Arguments":{  
            "QueueUrl":"https://sqs.us-east-1.amazonaws.com/account-id/myQueue",
            "MessageBody":{  
               "Input" : "{% $states.input.message %}",
               "MyTaskToken" : "{% $states.context.Task.Token %}"
            }
         },
         "End":true
      }
   }
}
```

## Optimized Amazon SQS APIs
<a name="connect-sqs-api"></a>
+ [https://docs.aws.amazon.com/AWSSimpleQueueService/latest/APIReference/API_SendMessage.html](https://docs.aws.amazon.com/AWSSimpleQueueService/latest/APIReference/API_SendMessage.html)

**Parameters in Step Functions are expressed in PascalCase**  
Even if the native service API is in camelCase, for example the API action `startSyncExecution`, you specify parameters in PascalCase, such as: `StateMachineArn`.

**Quota for input or result data**  
When sending or receiving data between services, the maximum input or result for a task is 256 KiB of data as a UTF-8 encoded string. See [Quotas related to state machine executions](service-quotas.md#service-limits-state-machine-executions).

## IAM policies for calling Amazon SQS
<a name="sqs-iam"></a>

The following example templates show how AWS Step Functions generates IAM policies based on the resources in your state machine definition. For more information, see [How Step Functions generates IAM policies for integrated services](service-integration-iam-templates.md) and [Discover service integration patterns in Step Functions](connect-to-resource.md).

*Static resources*

****  

```
{
    "Version":"2012-10-17",		 	 	 
    "Statement": [
        {
            "Effect": "Allow",
            "Action": [
                "sqs:SendMessage"
            ],
            "Resource": [
                "arn:aws:sqs:us-east-1:123456789012:myQueueName"
            ]
        }
    ]
}
```

*Dynamic resources*

****  

```
{
    "Version":"2012-10-17",		 	 	 
    "Statement": [
        {
            "Effect": "Allow",
            "Action": [
                "sqs:SendMessage"
            ],
            "Resource": "*"
        }
    ]
}
```