We are taking over a whole application from another company, and they have built the whole pipeline for deploying, but we still don't have access to it. What we know, that there's a lambda function is running triggered by certain SNS messages, and all the code is in Node.js, and the development is in VS Code. We also have issues debugging it locally, but it's a bigger problem, that we need to debug it remotely.
Since I am new in AWS services, I'd really appreciate if somebody could help me in this. Does it necessary to open a port? How is it possible to connect to a lambda? Do we need serverless to setup? Many unresolved questions.
I don't think there is way you can debug a lambda function remotely. Your best bet is to download the code on local machine, setup the env variables as you have set up on your lambda function and take it from there.
Remember at the end of the day lambda is just a container which is running the code for you. AWS doesn't allow any ssh or connection with those container. In your case you should be able to debug it on local till you have the same env variables. There are other things as well which are lambda specific but considering it is a running code which you have got so you should be able to find out the issue.
Hope it makes sense.