Implement a HttpService backend that runs on the AWS Lambda Rust Runtime

[kanru]

Description

Add a new server backend that runs on the aws-lambda-rust-runtime. Example usage:

fn main() {
    let mut app = tide::App::new(());
    app.at("/").get(async move |_| "Hello, world!");
    http_service_lambda::run(app.into_http_service());
}

Motivation and Context

Because I wanted to use a framework like tide to handle requests in a Lambda function.
Related issue: #10

How Has This Been Tested?

Build the example code and deployed to a Lambda function. I also ported one app that uses tide to Lambda.

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have read the CONTRIBUTING document.
• I have added tests to cover my changes.
• All new and existing tests passed.

[secretfader]

I made a few comments in-line on this PR, but otherwise it looks solid and gets my approval. 👍

[secretfader]

I pushed a change that resolves dependencies in this repo via path, and Tide via Git. It seems to have exposed one place where the API wasn't quite up-to-date with master, and I resolved that.

All in all, I think this is a really solid contribution and I'm glad you made it. We can hopefully get this merged shortly.

[secretfader]

@rustasync/maintainers LGTM. Could someone else review before merging?

[Nemo157]

Awesome to see more http-service implementations, just made a couple small comments, really don't care about the spelling issue, but the distinction between text and binary data makes me wonder if there's an issue in having http-service require all bodies to be Vec<u8> equivalents instead of allowing more structured bodies through.

[secretfader]

It does seem like we should explore the topic of structured bodies. That will probably be useful conversation if we aim to support other protocols, like gRPC, in the future.

Thanks, @Nemo157 for catching that.