Node Lambda: MySQL query never runs - mysql

Question

Testing with Postman, I'll try to make this as clear as possible, please advise if this is not making sense.
I have a Lambda that uses MySQL RDS database on AWS and works fine locally when accessing the database on AWS. After successfully getting a JWT from an auth endpoint I try to hit the login endpoint and I get a 502 Bad Gateway. Using the CloudWatch logs I can trace the failure to right before the login query runs. I've confirmed that my MySQL config is correct and that I have a connection to the database. The lambda and the database are in the same region DB: us-east-1f, lambda: us-east-1.
I've confirmed the OPTIONS and POST request methods for this endpoint both are set up with CORS enabled in the API Gateway. I'm using my serverless.yml to set cors: true on all the endpoints even though I'm using app.use(cors()) in my index file.
The error message for the 502 is, {"message": "Internal server error"}
Here is the point of failure in my code:
'use strict';
const mysql = require('./index');
module.exports = {
loginSql: async (email, password) => {
// MAKES IT HERE AND THE PARAMS ARE CORRECT
try {
console.log('IN TRY %%%%%%%%%%%%%%');
// SEEMS TO DIE HERE
const results = await mysql.query({
sql: `SELECT
id, first_name, last_name, email
FROM users
WHERE email = ?
AND password = ?`,
timeout: 50000,
values: [email, password],
});
// NEVER MAKES IT HERE /////////
console.log('QUERY RAN %%%%%%%%%%%%');
mysql.end();
if (results.length < 1) return false;
return results;
} catch (error) {
// DOESN'T THROW ERROR
console.log('LOGIN DB ERROR', error);
throw new Error('LOGIN DB ERROR THROWN', error);
}
},
};

Answer 1

I just created the exact same use case in that I have a LAMBDA function written in Java querying data from a MySQL RDS instance. It works perfectly.
Here is your issue:
To connect to the RDS instance from a Lambda function, you must set the inbound rules using the same security group as the RDS Instance. For details, How do I configure a Lambda function to connect to an RDS instance?.