Internal Server Error - Serverless, Lambda, Nestjs - aws-lambda

Question

I have a Nestjs application, which I am deploying to AWS Lambda and Serverless.
In the root of my application I have a serverless.ts -
import { NestFactory } from '#nestjs/core';
import { AppModule } from './app.module';
import serverlessExpress from '#vendia/serverless-express';
import { Handler, Callback, Context } from 'aws-lambda';
let server: Handler;
async function bootstrap() {
const app = await NestFactory.create(AppModule);
await app.init();
const expressApp = app.getHttpAdapter().getInstance();
return serverlessExpress({ app: expressApp });
}
bootstrap();
export const handler: Handler = async (
event: any,
context: Context,
callback: Callback,
) => {
server = server ?? (await bootstrap());
return server(event, context, callback);
};
serverless.yaml -
service: prism-backend
frameworkVersion: '3'
useDotenv: true
plugins:
- serverless-offline
provider:
name: aws
runtime: nodejs14.x
region: ap-south-1
functions:
main:
handler: dist/serverless.handler
events:
- http:
method: ANY
path: /
- http:
method: ANY
path: '{proxy+}'
package:
patterns:
- '!node_modules/**'
When I deploy this using 'serverless deploy` deployment is successful and I get generated endpoints.
When I access the default endpoint, I always get this in my browser -
{message: 'Internal Server Error' }
Do I need to configure something else? How can I resolve this?

Answer 1

Have you tried to use API Gateway test feature to call your function ?
Do you have a controller listening to the default endpoint of your application ? Watchout that by default, serverless appends the stage to your API. By default, the stage is dev. So your default endpoint should be "/dev/
Have you taken a look into cloudwatch already ? If so, could you please paste the logs here ?