How to Use Custom Authorizer for Aws Api Gateway

The customer authoriser is a lambda you created. API gateway use it to authorize the client requests for the configured APIs. Which accepts token, verify it and return IAM policy.

For a valid policy, API Gateway caches the returned policy, associated with the incoming token and used for the current and subsequent requests, over a pre-configured time-to-live (TTL) period of up to 3600 seconds. You can set the TTL period to zero seconds to disable the policy caching. The default TTL value is 300 seconds. Currently, the maximum TTL value of 3600 seconds cannot be increased.

Serverless framework supports this feature by setting resultTtlInSeconds in authorizer.

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- http:
    path: partners
    method: get
    integration: lambda
    authorizer:
      name: Authorizer
      identitySource: method.request.header.Authorization
      resultTtlInSeconds: 180

ref:
https://aws.amazon.com/blogs/compute/introducing-custom-authorizers-in-amazon-api-gateway/
https://github.com/awslabs/aws-apigateway-lambda-authorizer-blueprints
http://docs.aws.amazon.com/apigateway/latest/developerguide/use-custom-authorizer.html