So I managed to get it going. I'm curious though, how can I type

event

in the

main

function? I'm coming from the serverless framework, where I would have used PreTokenGenerationTriggerEvent from

@types/aws-lambda

, but this results in a typescript error as it's not compatible with the type of

callback: main

in the lambda function definition.

import * as aws from '@pulumi/aws'
import { HASURA_USER_ID_ATTRIBUTE_NAME, getName } from '../constants'
import { HASURA_ACCESS_TOKEN_NAMESPACE } from '../../../constants'

const functionName = getName('cognitoPreTokenGeneration')

function main(event: any) {
  const {
    sub,
    [`custom:${HASURA_USER_ID_ATTRIBUTE_NAME}`]: hasuraUserId,
  } = event.request.userAttributes

  if (!hasuraUserId) {
    console.error(message)
    throw Error(message)
  }

  event.response = {
    claimsOverrideDetails: {
      claimsToAddOrOverride: {
        [HASURA_ACCESS_TOKEN_NAMESPACE]: JSON.stringify({
          'x-hasura-allowed-roles': ['user'],
          'x-hasura-default-role': 'user',
          'x-hasura-user-id': hasuraUserId,
        }),
      },
    },
  }

  return event
}

export const preTokenGenerationLambda = new aws.lambda.CallbackFunction(
  functionName,
  {
    callback: main,
    runtime: 'nodejs14.x',
    memorySize: 128,
    timeout: 25,
  },
)