Using lambda authorizer in serverless function exposed through API gateway - aws-lambda

Question

I have written a lambda authorizer which returns response in this format -
{
principalId: 123345,
policyDocument: {
"Version": "2012-10-17",
"Statement": [
{
"Action": "execute-api:Invoke",
"Effect": "Allow",
"Resource": "arn:aws:execute-api:us-east-1:123456789012:ivdtdhp7b5/verifyToken-stage/GET/"
}
]
}
}
Note- My authorizer's name is verifyToken
In my different microservice(i.e Activity Logs) serverless.yml file
I am calling it like this -
service: activity-logs
frameworkVersion: '2'
resources:
Resources:
GatewayResponseUnauthorized:
Type: 'AWS::ApiGateway::GatewayResponse'
Properties:
ResponseParameters:
gatewayresponse.header.Access-Control-Allow-Origin: "'*'"
gatewayresponse.header.Access-Control-Allow-Headers: "'*'"
gatewayresponse.header.Access-Control-Allow-Methods: "'*'"
gatewayresponse.header.Access-Control-Allow-Credentials: "'true'"
ResponseType: UNAUTHORIZED
RestApiId:
Ref: 'ApiGatewayRestApi'
provider:
name: aws
runtime: nodejs12.x
lambdaHashingVersion: 20201221
region: us-east-1
stage: ${opt:stage}
functions:
getActivityLogs:
handler: handler.getActivityLogs
environment:
NODE_ENV: ${opt:env}
timeout: 800
events:
- http:
path: /{user_id}
method: get
authorizer: arn:aws:lambda:us-east-1:123456789012:function:auth-${opt:stage}-verifyToken
cors: true
vpc:
securityGroupIds:
- sg-xxxxxxxx
- sg-xxxxxxxx
- sg-xxxxxxxx
- sg-xxxxxxxx
- sg-xxxxxxxx
subnetIds:
- subnet-xxxxxxxxxxxxxxxxx
- subnet-xxxxxxxxxxxxxxxxx
I have checked my authorizer separately, it is working and returning 200 with the above response. Similarly, my microservice is working without authorizer. But when authorizer is enabled in getActivityLogs, it is not letting my activity-logs execute a single line

Answer 1

I was using callback for returning response in async function and as per this doc, https://docs.aws.amazon.com/lambda/latest/dg/nodejs-handler.html
we can simply return our response if a function is async.