Cfn-api-gateway-model NPM

cfn-api-gateway-model

Purpose

AWS CloudFormation does not support AWS API Gateway. This is a Lambda-backed custom resource to add the AWS API Gateway's Model to CloudFormation.

This package on NPM
This package on GitHub

Implementation

This Lambda makes use of the Lambda-Backed CloudFormation Custom Resource flow module, cfn-lambda (GitHub / NPM).

Usage

See ./example.template.json for a sample CloudFormation template. The example uses Condition statements, Parameters, and dynamic ServiceToken generation fully.

"ModelLogicalIdInResourcesObject": {
  "Type": "Type": "Custom::ApiGatewayModel",
  "Properties": {
    "ServiceToken": "arn:aws:lambda:<cfn-region-id>:<your-account-id>:function:<this-deployed-lambda-name>",
    "RestApiId": "abcdefghij", // REQUIRED 10 char alphanum for RestApi id
    "Name": "FooModel", // REQUIRED name of the Model
    "ContentType": "application/json", // REQUIRED MUST BE EXACTLY application/json
    "Schema": SomeJSONObject || "JSON String", // REQUIRED
    "Description": "some text", // OPTIONAL description of model
  }
}

`Ref` and `Fn::GetAtt`

Ref returns [RestApiId, Name, ContentType].join(':') and is only used for internal state tracking.

Fn::GetAtt can be used with "SchemaString" to get the JSON String representing the Schema of the model..

Example Template Prerequisites

Though this resource works by itself, the example template in this repository also makes use of other resources in this custom family. You need to install these in your cloud to use the sample template.

Custom::ApiGatewayRestApi (GitHub / NPM)

Installation of the Resource Service Lambda

Using the Provided Instant Install Script

The way that takes 10 seconds...

# Have aws CLI installed + permissions for IAM and Lamdba
$ npm run cfn-lambda-deploy

You will have this resource installed in every supported Region globally!

Using the AWS Console

... And the way more difficult way.

IMPORTANT: With this method, you must install this custom service Lambda in each AWS Region in which you want CloudFormation to be able to access the ApiGatewayModel custom resource!

Go to the AWS Lambda Console Create Function view:

Zip this repository into /tmp/ApiGatewayModel.zip
$ cd $REPO_ROOT && zip -r /tmp/ApiGatewayModel.zip;
Enter a name in the Name blank. I suggest: CfnLambdaResouce-ApiGatewayModel
Enter a Description (optional).
Toggle Code Entry Type to "Upload a .ZIP file"
Click "Upload", navigate to and select /tmp/ApiGatewayModel.zip
Set the Timeout under Advanced Settings to 10 sec
Click the Role dropdown then click "Basic Execution Role". This will pop out a new window.
Select IAM Role, then select option "Create a new IAM Role"
Name the role lambda_cfn_api_gateway_model (or something descriptive)
Click "View Policy Document", click "Edit" on the right, then hit "OK"
Copy and paste the ./execution-policy.json document.
Hit "Allow". The window will close. Go back to the first window if you are not already there.
Click "Create Function". Finally, done! Now go to Usage or see the example template. Next time, stick to the instant deploy script.