Serverless, connection to AWS RDS - mysql

Question

i'm attempting to connect to an AWS RDS database, however I can't seem to get my function to even attempt to connect.
This is my function:
export const connectTest = async (event, context) => {
let mysql = require('mysql');
let connection = mysql.createConnection({
host : process.env.RDS_HOSTNAME,
user : process.env.RDS_USERNAME,
password : process.env.RDS_PASSWORD,
port : process.env.RDS_PORT
});
let result = await connect(connection);
connection.end();
return {
statusCode: 200,
body: JSON.stringify({
message: result
})
};
};
const connect = () => new Promise((resolve, reject) => connection => {
connection.connect(function(err) {
if (err) {
reject(`Error ${err.message}`);
}
resolve('Connected');
});
});
And this is the response I get after running the following command:
Command: serverless invoke local --function connectTest
λ serverless invoke local --function connectTest
Serverless: DOTENV: Loading environment variables from .env:
Serverless: - RDS_HOSTNAME
Serverless: - RDS_USERNAME
Serverless: - RDS_PASSWORD
Serverless: - RDS_PORT
Serverless: Bundling with Webpack...
As you can see the script just ends, I don't get either of the messages.

Answer 1

If you want to conenct to an RDS instance from a Lambda function (I assume this is what you mean by Serverless), then check the details here: https://docs.aws.amazon.com/lambda/latest/dg/services-rds-tutorial.html
To connect to RDS from code or a tool running on your development machine (it does matter if the code is Java, JavaScript, Python, etc), you need to perform these tasks:
Ensure that the RDS instance is configured to allow Public Access.
Set the inbound rules to let the IP address of your development machine connect.
For information about setting up security group inbound rules, see Controlling Access with Security Groups.