Serverless-offline: Support for ALB to Lambda Integration

[MattCopenhaver]

With the relatively recent introduction of ALB as a way to invoke Lambda functions via HTTP(S), is this something that should supported by serverless-offline? There seems to be less manipulation done at the ALB level compared to what API Gateway does (more of that is pushed to the Lambda function itself), but the manipulation is different.

I'll let the AWS docs explain the reasons why you'd want to use ALB over API Gateway.
https://aws.amazon.com/about-aws/whats-new/2018/11/alb-can-now-invoke-lambda-functions-to-serve-https-requests/
https://docs.aws.amazon.com/elasticloadbalancing/latest/application/lambda-functions.html

Is this something that should be supported by serverless-offline?

[dherault]

Hi @MattCopenhaver
Serverless-offline is more an APIG-lambda emulator than anything else. But I would glaadly accept a PR making it a ALB emulator as well.
Cheers,

[dherault]

Where is Serverless on this ? Did they implement anything related to ALB ?

[MattCopenhaver]

I don't think they have yet.

https://github.com/serverless/serverless/issues/5572

The feature isn't very well documented by AWS, in my opinion. I've built a few simple use case integrations with a combination of using the AWS docs and trial/error, but I'm hesitant to try to build a "complete" emulator for ALB without the documentation from AWS as to what "complete" is.

[dnalborczyk]

seems like this was recently implemented in serverless. https://github.com/serverless/serverless/issues/5572#issuecomment-488271806 not sure about the feasibility of an implementation in serverless-offline though.

[adambiggs]

ALB support is now merged: https://github.com/serverless/serverless/pull/6073

I would love to see support added in serverless-offline :)

[dwelch2344]

Also looking for this. Happy to contribute, if someone could provide some guidance. Been a while since I've been in this codebase ;)

[dherault]

I eventually think this has to go into a separate plugin. Like serverless-offline-alb.

[chamathsilva]

I would like to contribute serverless-offline-alb like plugin

[dnalborczyk]

@dwelch2344 @chamathsilva feel free to create a PR!

[dwelch2344]

@dnalborczyk I'm circling back to serverless world soon, so this could be a good time for me. Could you give me some guidance / a write up on how you'd approach the solution?

I'm happy to do the research and legwork of it, but not sure where to get started / how best to integrate. I've written one or two plugins that built on / modified serverless-offline, and they were both (very fun) failures :P

[mlg-rbalhorn]

+1

[tmaslen]

Started working on a locally running ALB plugin...

https://github.com/tmaslen/serverless-local-alb-example

[horaciomo]

Hello, any update on this? Not pushing or requesting, just want to know what are the plans on this in order to make decision about how to design the Serverless architecture for our apps.

Thanks!

[jdrydn]

@horaciomo I'd recommend using the ALB anyway, and writing unit-tests for your functions to ensure they're working as expected, until such support comes to this plugin? That way, you can still use the ALB, plan your architecture with no interruptions & take advantage of such updates as-and-when?

[shadrech]

Anyway this can be supported @dnalborczyk @dherault . Would really make our dev lives much easier, especially since ALB seems to be a really good alternative to API Gateway. Even happy to reward with a couple of coffees for this feature 😉

Thanks

[sprksh]

Yeah badly needed.

[shadrech]

Been tryna open a bounty for this but site is acting up (http://bountysource.com). If someone manages to open up I'll gladly contribute

[terozio]

Anyone planning to work on this? It would be super useful to have the offline support for ALB!

[sps-software]

+1

[JackHowa]

Started working on a locally running ALB plugin...

https://github.com/tmaslen/serverless-local-alb-example

thanks for looking into this @tmaslen. I tried running this locally but I'm getting an error. I've tried looking in npm for this plugin as well. I'm not sure if I'm missing a step. let me know if I can help! Looks like there was another issue in the pr opened that suggested a folder that may need to be committed? thanks again, this could be a gamechanger for serverless-offline https://github.com/tmaslen/serverless-local-alb-example/issues/1

```
Serverless Error ---------------------------------------

Serverless plugin "offlinealb" not found. Make sure it's installed and listed in the "plugins" section of your serverless config file.

[tmaslen]

Hi,

Sorry about that. When I checked the code in I didn't realise it had skipped the .serverless_plugins directory.

Fixed it now. Pull down the latest version and try again.

Thanks,
/t