cdk-http-openapi

CDK Construct that lets you build AWS Api Gateway Http Api, backed by Lambdas, based on a OpenAPI spec file.

Features

- [x] Deploy Api Gateway Http Api based on a OpenAPI spec file.
- [x] Each API Route will be backed by 1 NodeJS lambda.
- [x] Configure CORS for your API.
- [x] Add custom domain (eg: https://my-awesome-api.my-domain.com) to your API.
- [x] Enable custom authorizers to Http Api Lambda integrations.
- [x] Customize your lambdas's memory, timeouts, log retention, env variables and other stuff.

Setup

Add latest package to your project with npm/yarn

``bash
npm i --save cdk-http-openapi
yarn add -D cdk-http-openapi
`




Start using cdk constructs in your infrastructure definition

Examples

1. Define an Http API + 1 lambda for each route

`typescript
import { HttpOpenApi } from 'cdk-http-openapi'
import { Construct } from 'constructs'
import { Stack } from 'aws-cdk-lib'

export class MyServiceStack extends Stack {
constructor(
scope: Construct,
id: string,
) {
super(scope, id)
// other resources for your microservice

// define your API + lambdas
const api = new HttpOpenApi(this, 'MyApi', {
functionNamePrefix: 'cool-api',
openApiSpec: './openapi.yml',
lambdasSourcePath: './dist/src', // optional. It defaults to './.build/src'
lambdasRuntime: lambda.Runtime.NODEJS_22_X, // optional. It defaults to lambda.Runtime.NODEJS_LATEST
integrations: [
{
operationId: 'getEntity', // for each operation you define in your OpenAPI spec
handler: 'api.getEntity', // you can register a lambda handler to handle your http request
},
{
operationId: 'storeEntity',
handler: 'api.storeEntity',
timeoutSeconds: 5, // timeout configuration for lambda
memorySize: 512, // memory configuration for lambda
env: { // you can also inject ENV variables into your lambda
DB_HOST: '...',
DB_USERNAME: '...',
DB_PASSWORD: '...'
},
}
]
});

}
}

`

2. Enable Custom Domain for your API: my-awesome-api.cool.io

`typescript
const api = new HttpOpenApi(this, 'MyApi', {
...
})

const domainName = 'my-awesome-api.cool.io';
const certificateArn = arn:aws:acm:${AWS_REGION}:${AWS_ACCOUNT}:certificate/${CERTIFICATE_ID};
const hostedZone = 'cool.io';

api.enableCustomDomain(domainName, certificateArn, hostedZone);
`

3. Configure wildcard CORS (allow '*')


`typescript
const api = new HttpOpenApi(this, 'MyApi', {
functionNamePrefix: 'my-service',
openApiSpec: './openapi.yml',

// ... other props

corsAllowAllOrigins: true,

});

`

4. Configure CORS more specific


`typescript
const api = new HttpOpenApi(this, 'MyApi', {
functionNamePrefix: 'my-service',
openApiSpec: './openapi.yml',

// ... other props

// See AWS Docs for more info: https://docs.aws.amazon.com/apigateway/latest/developerguide/http-api-cors.html
corsConfig: {
allowMethods: ['GET', 'POST'],
allowHeaders: ['application/json', 'authorization'],
allowOrigins: ['https://my-frontend.com']
}
});
`

5. Enable Customer Authorizer Lambda for your endpoints


`typescript
const api = new HttpOpenApi(this, 'MyApi', {
functionNamePrefix: 'my-service',
openApiSpec: './openapi.yml',

// ... other props

customAuthorizerLambdaArn: arn:aws:lambda:${AWS_REGION}:${AWS_ACCOUNT}:function:${AUTHORIZER_LAMBDA_NAME}

});
``

Credits

Based on the work by iDanielBot (https://github.com/iDanielBot/cdk-http-openapi.git);