# CloudFormation resources generated when AWS::Serverless::Function is specified
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When an `AWS::Serverless::Function` is specified, AWS Serverless Application Model (AWS SAM) always creates an `AWS::Lambda::Function` base CloudFormation resource.

**`AWS::Lambda::Function`**  
*`LogicalId`: *`<function‑LogicalId>`  
*Referenceable property: *N/A (you must use the `LogicalId` to reference this CloudFormation resource)

In addition to this CloudFormation resource, when `AWS::Serverless::Function` is specified, AWS SAM also generates CloudFormation resources for the following scenarios.

**Topics**
+ [Core function properties](#sam-specification-generated-resources-function-core-properties)
+ [Event sources](#sam-specification-generated-resources-function-event-sources)
+ [Event configuration](#sam-specification-generated-resources-function-event-configuration)

## Core function properties
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The following scenarios generate CloudFormation resources based on core function properties:

### Role property is not specified
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When the `Role` property of an `AWS::Serverless::Function` is *not* specified, AWS SAM generates an `AWS::IAM::Role` CloudFormation resource.

**`AWS::IAM::Role`**  
*`LogicalId`: *`<function‑LogicalId>Role`  
*Referenceable property: *N/A (you must use the `LogicalId` to reference this CloudFormation resource)

### AutoPublishAlias property is specified
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When the `AutoPublishAlias` property of an `AWS::Serverless::Function` is specified, AWS SAM generates the following CloudFormation resources: `AWS::Lambda::Alias` and `AWS::Lambda::Version`.

**`AWS::Lambda::Alias`**  
*`LogicalId`: *`<function‑LogicalId>Alias<alias‑name>`  
`<alias‑name>` is the string that `AutoPublishAlias` is set to. For example, if you set `AutoPublishAlias` to `live`, the `LogicalId` is: *MyFunction*Alias*live*.  
*Referenceable property: *`<function‑LogicalId>.Alias`

**`AWS::Lambda::Version`**  
*`LogicalId`: *`<function‑LogicalId>Version<sha>`  
`<sha>` is a unique hash value that is generated when the stack is created. For example, *MyFunction*Version*926eeb5ff1*.  
*Referenceable property: *`<function‑LogicalId>.Version`

For additional information on the `AutoPublishAlias` property, see the [Properties section of AWS::Serverless::Function](sam-resource-function.md#sam-resource-function-properties).

### DeploymentPreference property is specified
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When the `DeploymentPreference` property of an `AWS::Serverless::Function` is specified, AWS SAM generates the following resources CloudFormation resources: `AWS::CodeDeploy::Application` and `AWS::CodeDeploy::DeploymentGroup`. In addition, if the `Role` property of the `DeploymentPreference` object is *not* specified, AWS SAM also generates an `AWS::IAM::Role` CloudFormation resource.

**`AWS::CodeDeploy::Application`**  
*`LogicalId`: *`ServerlessDeploymentApplication`  
*Referenceable property: *N/A (you must use the `LogicalId` to reference this CloudFormation resource)

**`AWS::CodeDeploy::DeploymentGroup`**  
*`LogicalId`: *`<function‑LogicalId>DeploymentGroup`  
*Referenceable property: *N/A (you must use the `LogicalId` to reference this CloudFormation resource)

**`AWS::IAM::Role`**  
*`LogicalId`: *`CodeDeployServiceRole`  
*Referenceable property: *N/A (you must use the `LogicalId` to reference this CloudFormation resource)

### FunctionUrlConfig property is specified
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When the `FunctionUrlConfig` property is specified, AWS SAM generates different CloudFormation resources based on the `AuthType`.

When `AuthType: NONE` is specified, AWS SAM generates the following CloudFormation resources:

**`AWS::Lambda::Permission` (Invoke Access)**  
*`LogicalId`: *`<function‑LogicalId>URLInvokeAllowPublicAccess`  
*Referenceable property: *N/A (you must use the `LogicalId` to reference this CloudFormation resource)

**`AWS::Lambda::Permission` (Public Access)**  
*`LogicalId`: *`<function‑LogicalId>UrlPublicPermissions`  
*Referenceable property: *N/A (you must use the `LogicalId` to reference this CloudFormation resource)

**`AWS::Lambda::Url`**  
*`LogicalId`: *`<function‑LogicalId>Url`  
*Referenceable property: *N/A (you must use the `LogicalId` to reference this CloudFormation resource)

When `AuthType: AWS_IAM` is specified, AWS SAM generates only:

**`AWS::Lambda::Url`**  
*`LogicalId`: *`<function‑LogicalId>Url`  
*Referenceable property: *N/A (you must use the `LogicalId` to reference this CloudFormation resource)

For additional information on the `FunctionUrlConfig` property, see [FunctionUrlConfig](sam-property-function-functionurlconfig.md).

## Event sources
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The following scenarios generate CloudFormation resources based on event sources:

### An Api event source is specified
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When the `Event` property of an `AWS::Serverless::Function` is set to `Api`, but the `RestApiId` property is *not* specified, AWS SAM generates the `AWS::ApiGateway::RestApi` CloudFormation resource.

**`AWS::ApiGateway::RestApi`**  
*`LogicalId`: *`ServerlessRestApi`  
*Referenceable property: *N/A (you must use the `LogicalId` to reference this CloudFormation resource)

### An HttpApi event source is specified
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When the `Event` property of an `AWS::Serverless::Function` is set to `HttpApi`, but the `ApiId` property is *not* specified, AWS SAM generates the `AWS::ApiGatewayV2::Api` CloudFormation resource.

**`AWS::ApiGatewayV2::Api`**  
*`LogicalId`: *`ServerlessHttpApi`  
*Referenceable property: *N/A (you must use the `LogicalId` to reference this CloudFormation resource)

### A streaming event source is specified
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When the `Event` property of an `AWS::Serverless::Function` is set to one of the streaming types, AWS SAM generates the `AWS::Lambda::EventSourceMapping` CloudFormation resource. This applies to the following types: `DynamoDB`, `Kinesis`, `MQ`, `MSK`, and `SQS`.

**`AWS::Lambda::EventSourceMapping`**  
*`LogicalId`: *`<function‑LogicalId><event‑LogicalId>`  
*Referenceable property: *N/A (you must use the `LogicalId` to reference this CloudFormation resource)

### An event bridge (or event bus) event source is specified
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When the `Event` property of an `AWS::Serverless::Function` is set to one of the event bridge (or event bus) types, AWS SAM generates the `AWS::Events::Rule` CloudFormation resource. This applies to the following types: `EventBridgeRule`, `Schedule`, and `CloudWatchEvents`.

**`AWS::Events::Rule`**  
*`LogicalId`: *`<function‑LogicalId><event‑LogicalId>`  
*Referenceable property: *N/A (you must use the `LogicalId` to reference this CloudFormation resource)

### An IotRule event source is specified
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When the `Event` property of an `AWS::Serverless::Function` is set to IoTRule, AWS SAM generates the `AWS::IoT::TopicRule` CloudFormation resource.

**`AWS::IoT::TopicRule`**  
*`LogicalId`: *`<function‑LogicalId><event‑LogicalId>`  
*Referenceable property: *N/A (you must use the `LogicalId` to reference this CloudFormation resource)

## Event configuration
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The following scenarios generate CloudFormation resources based on event configuration:

### OnSuccess (or OnFailure) property is specified for Amazon SNS events
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When the `OnSuccess` (or `OnFailure`) property of the `DestinationConfig` property of the `EventInvokeConfig` property of an `AWS::Serverless::Function` is specified, and the destination type is `SNS` but the destination ARN is *not* specified, AWS SAM generates the following CloudFormation resources: `AWS::Lambda::EventInvokeConfig` and `AWS::SNS::Topic`.

**`AWS::Lambda::EventInvokeConfig`**  
*`LogicalId`: *`<function‑LogicalId>EventInvokeConfig`  
*Referenceable property: *N/A (you must use the `LogicalId` to reference this CloudFormation resource)

**`AWS::SNS::Topic`**  
*`LogicalId`: *`<function‑LogicalId>OnSuccessTopic` (or `<function‑LogicalId>OnFailureTopic`)  
*Referenceable property: *`<function‑LogicalId>.DestinationTopic`  
If both `OnSuccess` and `OnFailure` are specified for an Amazon SNS event, to distinguish between the generated resources, you must use the `LogicalId`.

### OnSuccess (or OnFailure) property is specified for Amazon SQS events
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When the `OnSuccess` (or `OnFailure`) property of the `DestinationConfig` property of the `EventInvokeConfig` property of an `AWS::Serverless::Function` is specified, and the destination type is `SQS` but the destination ARN is *not* specified, AWS SAM generates the following CloudFormation resources: `AWS::Lambda::EventInvokeConfig` and `AWS::SQS::Queue`.

**`AWS::Lambda::EventInvokeConfig`**  
*`LogicalId`: *`<function‑LogicalId>EventInvokeConfig`  
*Referenceable property: *N/A (you must use the `LogicalId` to reference this CloudFormation resource)

**`AWS::SQS::Queue`**  
*`LogicalId`: *`<function‑LogicalId>OnSuccessQueue` (or `<function‑LogicalId>OnFailureQueue`)  
*Referenceable property: *`<function‑LogicalId>.DestinationQueue`  
If both `OnSuccess` and `OnFailure` are specified for an Amazon SQS event, to distinguish between the generated resources, you must use the `LogicalId`.