docs: add referable properties of sam resources (#1468)

Author: Shreya

versions/2016-10-31.md

@@ -16,6 +16,7 @@ The AWS Serverless Application Model (SAM) is licensed under [The Apache License
   * [Event source types](#event-source-types)
   * [Property types](#property-types)
   * [Data types](#data-types)
+  * [Referable properties of SAM resources](#referable-properties-of-sam-resources)
 
 
 ## Introduction
@@ -1273,3 +1274,34 @@ CorsConfiguration:
       ExposeHeaders:
         - "*"
 ```
+
+### Referable properties of SAM resources
+- [AWS::Serverless::Function](#referable-properties-of-serverless-function)
+- [AWS::Serverless::Api](#referable-properties-of-serverless-RestApi)
+- [AWS::Serverless::HttpApi](#referable-properties-of-serverless-HttpApi)
+
+#### Referable properties of Serverless Function
+Property Name | Reference | LogicalId | Description
+---|:---:|---|---
+Alias | `function-logical-id`.Alias | `function-logical-id`Alias`alias-name` | SAM generates an `AWS::Lambda::Alias` resource when `AutoPublishAlias` property is set. This resource can be referenced in intrinsic functions by using the resource logical ID or  `function-logical-id`.Alias
+Version | `function-logical-id`.Version | `function-logical-id`Version`sha` | SAM generates an `AWS::Lambda::Version` resource when `AutoPublishAlias` property is set. This resource can be referenced in intrinsic functions by using the resource logical ID or  `function-logical-id`.Version
+DestinationTopic | `function-logical-id`.DestinationTopic |`function-logical-id`EventInvokeConfig`OnSuccess/OnFailure`Topic| SAM auto creates an `AWS::SNS::Topic` resource when `Destination` property of `DestinationConfig` property in `EventInvokeConfig` property is not specified. This generated resource can be referenced by using `function-logical-id`.DestinationTopic
+DestinationQueue | `function-logical-id`.DestinationQueue |`function-logical-id`EventInvokeConfig`OnSuccess/OnFailure`Queue | SAM auto creates an `AWS::SQS::Queue` resource when `Destination` property of `DestinationConfig` property in `EventInvokeConfig` property is not specified. This generated resource can be referenced by using `function-logical-id`.DestinationQueue
+
+#### Referable properties of Serverless RestApi
+
+Property Name | Reference | LogicalId | Description
+---|:---:|---|---
+Stage | `restapi-logical-id`.Stage | `restapi-logical-id` `StageName`Stage | SAM generates `AWS::ApiGateway::Stage` resource when `AWS::Serverless::Api` resource is defined. This resource can be referenced in intrinsic function using the resource logical id or `restapi-logical-id`.Stage
+Deployment | `restapi-logical-id`.Deployment | `restapi-logical-id`Deployment`sha` | SAM generates `AWS::ApiGateway::Deployment` resource when `AWS::Serverless::Api` resource is defined. This resource can be referenced in intrinsic function using the resource logical id or `restapi-logical-id`.Deployment
+DomainName | `restapi-logical-id`.DomainName | `domain-logical-id` | `AWS::ApiGateway::DomainName` resource can be referenced by using the resource logical id or `restapi-logical-id`.DomainName when `DomainName` resource is defined in `Domain` property of `AWS::Serverless::Api`
+UsagePlan | `restapi-logical-id`.UsagePlan | `restapi-logical-id`UsagePlan | SAM generates UsagePlan, UsagePlanKey and ApiKey resources when `UsagePlan` property is set. UsagePlan resource can be referenced in intrinsic function using the resource logical id or `restapi-logical-id`.UsagePlan
+UsagePlanKey | `restapi-logical-id`.UsagePlanKey |`restapi-logical-id`UsagePlanKey | SAM generates UsagePlan, UsagePlanKey and ApiKey resources when `UsagePlan` property is set. UsagePlanKey resource can be referenced in intrinsic function using the resource logical id or `restapi-logical-id`.UsagePlanKey
+ApiKey | `restapi-logical-id`.ApiKey |`restapi-logical-id`ApiKey | SAM generates UsagePlan, UsagePlanKey and ApiKey resources when `UsagePlan` property is set. ApiKey resource can be referenced in intrinsic function using the resource logical id or `restapi-logical-id`.ApiKey
+        
+#### Referable properties of Serverless HttpApi
+
+Property Name | Reference | LogicalId | Description
+---|:---:|---|---
+Stage | `httpapi-logical-id`.Stage | `httpapi-logical-id`ApiGatewayDefaultStage or `httpapi-logical-id` `StageName`Stage | SAM generates `AWS::ApiGatewayV2::Stage` resource with `httpapi-logical-id`ApiGatewayDefaultStage logical id if `StageName` property is not defined. If an explicit `StageName` property is defined them SAM generates `AWS::ApiGatewayV2::Stage` resource with `httpapi-logical-id` `StageName`Stage logicalId. This resource can be referenced in intrinsic functions using `httpapi-logical-id`.Stage
+DomainName | `httpapi-logical-id`.DomainName | `domain-logical-id` | `AWS::ApiGatewayV2::DomainName` resource can be referenced by using the resource logical id or `restapi-logical-id`.DomainName when `DomainName` resource is defined in `Domain` property of `AWS::Serverless::Api`