# OnFailure
<a name="sam-property-function-onfailure"></a>

A destination for events that failed processing.

## Syntax
<a name="sam-property-function-onfailure-syntax"></a>

To declare this entity in your AWS Serverless Application Model (AWS SAM) template, use the following syntax.

### YAML
<a name="sam-property-function-onfailure-syntax.yaml"></a>

```
  [Destination](#sam-function-onfailure-destination): String
  [Type](#sam-function-onfailure-type): String
```

## Properties
<a name="sam-property-function-onfailure-properties"></a>

 `Destination`   <a name="sam-function-onfailure-destination"></a>
The Amazon Resource Name (ARN) of the destination resource.  
*Type*: String  
*Required*: Conditional  
*CloudFormation compatibility*: This property is similar to the `[OnFailure](https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/aws-properties-lambda-eventinvokeconfig-onfailure.html)` property of an `AWS::Lambda::EventInvokeConfig` resource. SAM will add any necessary permissions to the auto-generated IAM Role associated with this function to access the resource referenced in this property.  
*Additional notes*: If the type is Lambda/EventBridge, Destination is required.

 `Type`   <a name="sam-function-onfailure-type"></a>
Type of the resource referenced in the destination. Supported types are `SQS`, `SNS`, `S3`, `Lambda`, and `EventBridge`.  
*Type*: String  
*Required*: No  
*CloudFormation compatibility*: This property is unique to AWS SAM and doesn't have an CloudFormation equivalent.  
*Additional notes*: If the type is SQS/SNS and the `Destination` property is left blank, then the SQS/SNS resource is auto generated by SAM. To reference the resource, use `<function-logical-id>.DestinationQueue` for SQS or `<function-logical-id>.DestinationTopic` for SNS. If the type is Lambda/EventBridge, `Destination` is required.

## Examples
<a name="sam-property-function-onfailure--examples"></a>

### EventInvoke Configuration Example with SQS and Lambda destinations
<a name="sam-property-function-onfailure--examples--eventinvoke-configuration-example-with-sqs-and-lambda-destinations"></a>

In this example no Destination is given for the SQS OnSuccess configuration, so SAM implicitly creates a SQS queue and adds any necessary permissions. Also for this example, a Destination for a Lambda resource declared in the template file is specified in the OnFailure configuration, so SAM adds the necessary permissions to this Lambda function to call the destination Lambda function.

#### YAML
<a name="sam-property-function-onfailure--examples--eventinvoke-configuration-example-with-sqs-and-lambda-destinations--yaml"></a>

```
EventInvokeConfig:
  DestinationConfig:
    OnSuccess:
      Type: SQS
    OnFailure:
      Type: Lambda
      Destination: !GetAtt DestinationLambda.Arn  # Arn of a Lambda function declared in the template file.
```

### EventInvoke Configuration Example with SNS destination
<a name="sam-property-function-onfailure--examples--eventinvoke-configuration-example-with-sns-destination"></a>

In this example a Destination is given for an SNS topic declared in the template file for the OnSuccess configuration.

#### YAML
<a name="sam-property-function-onfailure--examples--eventinvoke-configuration-example-with-sns-destination--yaml"></a>

```
EventInvokeConfig:
  DestinationConfig:
    OnSuccess:
      Type: SNS
      Destination:
        Ref: DestinationSNS       # Arn of an SNS topic declared in the tempate file
```