Add support for lambdas running on custom endpoints (e.g. localstack)

[PavlosMelissinos]

As far as I can tell, blambda uses the default AWS endpoint URL, which makes it incompatible with localstack.

Using a client such as the following would solve the problem:

    (aws/client {:api               :lambda
                 :region            aws-region
                 :endpoint-override {:protocol :http
                                     :hostname "localhost"
                                     :port     4566}})

Unfortunately AWS doesn't yet provide a way to set the endpoint in .aws/credentials or with an env var. Would you consider exposing the endpoint URL in the API as well as the CLI as an optional input, so that users can override the current behaviour?

Thanks a lot for blambda! It has simplified the process of writing lambdas in Clojure quite a bit :)

[jmglov]

Sorry for the late reply on this. I didn't see the notification for the issue when it was created.

If you want to open a pull request for this functionality, I'd be happy to have a look at it. :)

[PavlosMelissinos]

I'll investigate a bit as soon as I find some time! However, I don't have the capacity right now unfortunately and it's not a huge priority for me, so it might take a while...