You added a custom authorizer using python or Node.js Lambda function. You added this Lambda function as custom authorizer in AWS API Gateway and successfully tested it with no issues. But when you tried to access it the API method using POSTMAN it showed the below error in console-


  • “Sun, 10 Mar 2019 19:42:29 GMT”
  • “application/json”
  • “16”
  • “keep-alive”
  • “a36add57-436c-23e9-bfab-fbedfr04bf32”
  • AuthorizerConfigurationException
  • “WV1afedgNywNBFeuQ=”


ThisĀ AuthorizerConfigurationException” is shown for all exceptions thrown by API Gateway during authorizer execution. There are different reasons.

You should enable Cloudwatch logs for the Lambda function to debug this issues correctly.

In my case the logs showed that the jwt token I was passing in my request have expired-


2019-03-10T20:21:46.608Z 2a0b5ea9-1abb-asfd-hfde-5a8cf2baa2b5 { TokenExpiredError: jwt expired
at Object.module.exports [as verify] (/var/task/node_modules/jsonwebtoken/verify.js:126:19)
at getSigningKey.then (/var/task/lib.js:63:24)
at <anonymous>
at process._tickDomainCallback (internal/process/next_tick.js:228:7)
name: ‘TokenExpiredError’,
message: ‘jwt expired’,
expiredAt: 2019-03-10T03:36:35.000Z }



Note: If the authorizer works fine while testing it in API Gateway then there is not problems in invoking or executing of Lambda function. The only thing to check is the parameters passed to the request from your client.