learn-rust-101 VS aws-lambda-rust-runtime

With an interest in many more, but the above were my main languages for a decennia.

9 years ago I picked up Go, and have used it the most as my main language since then. 7 Years ago I picked up Rust, but only since 6 months ago really intensive (including publishing the guide that came out of my experience at https://rust-lang.guide/).

Over those 7 years I've only done a production project around the start of that journey and now since 6 months ago I'm writing production code in it again and haven't stopped since. But I've learned the language like 3 different times in that journey.

It's not an easy one to get into. A lot of things to wrap your head around, especially if your goal is to really master it, rather then just "woohoo I can compile my program". I still not master it, but I do feel now fluent in it and can express my ideas well. There are also no more fights with the language or its tooling.

Compared to that, Go(lang) is super easy to get into. Ridiculously easy. Perhaps too easy. You can give it to a programmer of any level, and they probably can ship their first feature that same day. The difference is however, that. First of all with Golang it's super easy to ship code with nil pointer exceptions in it or data races. I've seen it in the best code bases. And sure, plenty of people will tell if you do it "right" you'll have no issues. I've hear similar comments from ex-colleagues still in the C++ world as well. Secondly, Golang is very opinionated and if you derive in ideas or needs a bit from what they want you to do, you are in a bit of a problem. This has been slightly improved, but it's still very limited and still a lot of magic that only built-in features can perform. And thirdly, the language is very minmal (Golang). So codebases look very verbose very quickly. Also harder to express ideas (as error support is limited, and sum types are not a thing, neither are other things like pattern matchings). It's also a lot less "functional".

This is not to compare Golang vs Rust too much, even though I did. My point was more, and I probably butcher my own comment not making that point well, is that I think it's fair to have a massive threshold for beginners to get into a programming language. As long as in return it means you get a very powerful tool in rerturn to do some of your work. And Rust is def. such a tool. Many people boast about how peformant it is. And while that is true, it is for me for most projects more of an extra benefit rather than the things I really like it for. What I like with Rust is that it gives me really high confidence in my code (comparable to projects I've written in Elm and Haskell in the past). When my project compiles I really am pretty confident it will not give me runtime surprises beyond mistakes elsewhere (e.g. infrastructure choices). It's a very expressive language and pleasant to use in that way.

And then there is of course the fact that it is truly FOSS, has a very nice community, great documentation and a lot of excellent learning resources.

I am not a fanboy of much, neither of Rust, but I do really appreciate its existence and I am happy to use it where it suits. Yes it is a massive threshold, but one worth to pay.

I've been writing more and more about the benefits of Rust and Lambda quite a bit lately and I plan to take advantage of them in this customizer. Additionally, I've leveraged the Lambda Runtime project that includes data structures for the Lambda Events that I'll encounter while working with these payloads.

The Lambda Rust Runtime project bridges that gap between SDK support and enhanced developer experience. Now this code IS flagged as experimental as it is subject to change. Didn't I just say above that I don't like experimental software in production? For something like a critical SDK into AWS, yes. But for something that is mostly data structures and working with different Lambda events, I don't have an issue. I'm comfortable with recommending builders look into this repository. I've also been fortunate to contribute to it and believe that the libraries included will make builder's lives easier. End of the day, if the experimental piece is a hold-up, a Lambda with Rust will be fine without it.

If you are building Rust applications that are deployed in Lambdas, it's well worth your time to check out this AWS project. And nestled inside that repository is a Lambda Events crate that helps with the serde/deserde of different payloads to be encountered when running Lambdas.

Feel free to take look at the GitHub repo and ask any questions you have there, we're always happy to help in what we can: https://github.com/awslabs/aws-lambda-rust-runtime

Rust on Lambda's using containers as the deployment artifact are also very good, i'd say a perfect match. Low artifact size, low cpu+memory usage, fast execution. I think AWS must be using increasingly using Rust on Lambda internally from the talks I've seen them publish and the work gone in to https://github.com/awslabs/aws-lambda-rust-runtime.

For simple REST API's there's not much extra effort in using Rust once you are familiar.

Check out the official AWS Lambda Rust project https://github.com/awslabs/aws-lambda-rust-runtime. It has a bunch of examples and we’ll designed. I got up and running knowing minimal Rust very quickly.

The official https://github.com/awslabs/aws-lambda-rust-runtime seems well architected.

Hi, maybe check out https://github.com/awslabs/aws-lambda-rust-runtime there's some examples in there.. But essentially you can build a Lambda function and deploy to your AWS account with this toolset.

use aws_lambda_events::apigw::{ ApiGatewayCustomAuthorizerRequestTypeRequest, ApiGatewayCustomAuthorizerResponse, ApiGatewayCustomAuthorizerPolicy, IamPolicyStatement, }; use lambda_runtime::{run, service_fn, Error, LambdaEvent}; use serde_json::json; #[tokio::main] async fn main() -> Result<(), Error> { tracing_subscriber::fmt() .with_ansi(false) .without_time() .with_max_level(tracing_subscriber::filter::LevelFilter::INFO) .init(); run(service_fn(function_handler)).await } pub async fn function_handler(event: LambdaEvent) -> Result { // do something with the event payload let method_arn = event.payload.method_arn.unwrap(); // for example we could use the authorization header if let Some(token) = event.payload.headers.get("authorization") { // do something with the token // my custom logic return Ok(custom_authorizer_response( "ALLOW", "some_principal", &method_arn, )); } Ok(custom_authorizer_response( &"DENY".to_string(), "", &method_arn)) } pub fn custom_authorizer_response(effect: &str, principal: &str, method_arn: &str) -> ApiGatewayCustomAuthorizerResponse { let stmt = IamPolicyStatement { action: vec!["execute-api:Invoke".to_string()], resource: vec![method_arn.to_owned()], effect: Some(effect.to_owned()), }; let policy = ApiGatewayCustomAuthorizerPolicy { version: Some("2012-10-17".to_string()), statement: vec![stmt], }; ApiGatewayCustomAuthorizerResponse { principal_id: Some(principal.to_owned()), policy_document: policy, context: json!({ "email": principal }), // https://github.com/awslabs/aws-lambda-rust-runtime/discussions/548 usage_identifier_key: None, } }

FYI, there’s an offical rust “runtime” in the works: https://github.com/awslabs/aws-lambda-rust-runtime