[AWS] APIGateway returns 500 error when being used with a custom Lambda Authorizer

Serverless Framework
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1

Hello everyone, I am trying to create an API in which some endpoints need to be authenticated. The authentication data(token) is being sent in the Cookie header.

My problem is that the API is returning 500 Internal Server Error { "message": null } whenever I am trying to request something. Cloud watch logs show that the API gateway is getting invoked, the lambda authorizer is getting invoked, but the function to process my request is not getting executed at all. No error logs.

When I test locally using serverless offline, it works fine. When I test my function by making it accessible without needing any authentication, it works fine. So my guess is that there’s some configuration error in my serverless template or the authorizer is not returning a valid response. Please have a look below:

serverless.yml:

frameworkVersion: '2'
org: companyx
app: customer-self-service-api
service: customer-self-service-api
custom:
  domains:
    production: customer-self-service.example.com
    development: dev-customer-self-service.example.com
    staging: stg-customer-self-service.example.com
  customDomain:
    domainName: ${self:custom.domains.${self:provider.stage}}
    basePath: ''
    stage: development
    createRoute53Record: true
  sentry:
    sourceMaps: true
    dsn: ${env:SENTRY_DSN}
    organization: companyx
    project: customer-self-service-api
    authToken: ${env:SENTRY_AUTH_TOKEN}
    release:
      version: true
plugins:
  - serverless-bundle
  - serverless-dotenv-plugin
  - serverless-domain-manager
  - serverless-offline
provider:
  stage: ${opt:stage, "development"}
  region: eu-central-1
  name: aws
  runtime: nodejs12.x
  apiGateway:
    shouldStartNameWithService: true
    minimumCompressionSize: 1024
  endpointType: regional
  environment:
    AWS_NODEJS_CONNECTION_REUSE_ENABLED: '1'
package:
  individually: true
functions:
  ping:
    handler: handler.ping
    events:
      - http:
          method: get
          path: api/v1/ping
  jwtAuth:
    handler: handler.jwtAuth
  getProfile:
    handler: handler.getProfile
    events:
      - http:
          method: get
          path: api/v1/customers/profile
          authorizer:
            name: jwtAuth
            type: request
            identitySource: method.request.header.Cookie
          cors: true

The response from Lambda Authorizer:

{
    "principalId": "myuser1@example.com",
    "policyDocument": {
        "Version": "2012-10-17",
        "Statement": [
            {
                "Action": "execute-api:Invoke",
                "Effect": "Allow",
                "Resource": "arn:aws:execute-api:eu-central-1:<my account id>:<api gw id>/<stage>/GET/api/v1/customers/profile"
            }
        ]
    },
    "context": {
        "user": {
            "email": "myuser1@example.com",
            "email_verified": true,
            "iat": 1619528494,
            "exp": 1622120494
        },
        "expires": "2031-03-08T17:45:21.809Z"
    }
}
2

I found out the issue. It’s because I was sending and object inside “context” and its not allowed to. We should only sent primitive datatypes: string, number, boolean