AspNetCoreDiagnosticScenarios VS Koa

Important: following #prefer-asyncawait-over-directly-returning-task from https://github.com/davidfowl/AspNetCoreDiagnosticScenarios/b... is not correct.

The concerns raised are niche and edge case and task must always be forwarded as is provided there is no post-processing or resource cleanup with idisposable.

This one is a pretty decent guide - https://github.com/davidfowl/AspNetCoreDiagnosticScenarios/blob/master/AsyncGuidance.md

The C# (mostly applicat community has e.g. https://github.com/davidfowl/AspNetCoreDiagnosticScenarios/blob/master/AsyncGuidance.md written by one of the Asp.Net architects. I found this in this lovely thread https://news.ycombinator.com/item?id=36785691 which expresses my views/confusion more clearly than I can express.

No it doesn't, hence why there are best practices guidelines written by the .NET architects, and there was a research project to add Go/Java co-routines as well.

https://github.com/davidfowl/AspNetCoreDiagnosticScenarios/b...

https://twitter.com/davidfowl/status/1532880744732758018?lan...

https://github.com/dotnet/runtimelab/issues/2057

https://github.com/dotnet/runtimelab/issues/2398

They don't work just fine in C#, there is a reason why one of ASP.NET architects has written a guide of best practices.

https://github.com/davidfowl/AspNetCoreDiagnosticScenarios/b...

Many that praise async/await in C#, kind of forget it took about 10 years to spread across all the layer of the language and runtime, since it was done via IL rewriting, it caused several issues with F# async tasks, due to the age of the ecosystem plenty of code isn't async/await friendly and needs to be wrapped into Task.Run() or similar.

There is a best practices guideline from one of the ASP.NET architects, https://github.com/davidfowl/AspNetCoreDiagnosticScenarios/b...

During last year they researched adding Go/Java's approach to .NET, but now it is too late. See the ASP.NET Q&A session at BUILD 2023.

The best guidance I have found was from here: AsyncGuidance.md

To expand upon this thought, here is the AsyncGuidance doc[1] on why not to use .Result to get the return value of a completed Task in C#.

To make this simple they introduced async Main[2] a few years ago.

[1]: https://github.com/davidfowl/AspNetCoreDiagnosticScenarios/b...

Async Guidance

Since "Express.js is an old framework that has not evolved for a long time. It's not a good choice for new projects since it can easily lead to security issues and memory leaks." -- H3. Which is also the case for Koa.

In this example, we're using the serverless framework to quickly set up the Lambda function along with an API gateway for the entry point. The lambda function is a simple Koa REST API with a few functional endpoints.

The initial step is to create our entry point, from where the page will be rendered. In this case, we will use the koa framework.

Koa.js: By the team behind Express, Koa.js utilized async/await for middleware, resulting in cleaner and more readable code.

Koa

Koa.js: https://koajs.com/

Koa -Next Generation Node Microservice Framework

Backend is more tricky. - RESTful APIs I prefer Koajs - For a RPC/microsevice, I have only used gRPC - For a CLI, yargs and inquirer

There are lot of different frameworks out there. If you learn one, there is no guarantee that the next job you find will use the same. For example if you learn Express and the next one used Koa or Nest.

Koa.js is a minimal and flexible Node.js web application infrastruc­ture, which provides a robust set of features for web and mobile applica­tions. It is an open-source framework developed and maintained by the creators of Express.js, the most popular web framework for Node.js.