reqwest VS tokio

> If you are equally picky and constrain yourself to parts of the ecosystem which care about binary size, you still have more options and can avoid size issues.

What's an example of this for, say, libcurl? On my system it has a tiny number of recursive dependencies, around a dozen. [0] Furthermore if I want to write a C program that uses libcurl I have to download zero bytes of data ... because it's a shared library that is already installed on my system, since so many programs already use it.

I don't really know the appropriate comparison for Rust. reqwest seems roughly comparable, but it's an HTTP client library, and not a general purpose network client like curl. Obviously curl can do a lot more. Even the list of direct dependencies for reqwest is quite long [1], and it's built on top of another http library [2] that has its own long list of dependencies, a list that includes tokio, no small library itself.

In terms of final binary size, the installed size of the curl package on my system, which includes both the command line tool and development dependencies for libcurl, is 1875.03 KiB.

[0] I'm excluding the dependency on the ca-certificates package, since this only provides the certificate chain for TLS and lots of programs rely on it.

[1] https://crates.io/crates/reqwest/0.11.24/dependencies

[2] https://crates.io/crates/hyper/0.14.28/dependencies

ReductStore was rewritten from C++ to Rust a few months ago. We are delighted to be part of the Rust community and have taken a new step towards Rust with the Client SDK. The SDK is powered by reqwest and enables asynchronous integration of the database into Rust applications:

From what I could turn up when googling the specific error lines (here), it has something to do with the crate mio not having support for WASM, but I don’t understand what’s being said on this thread.

When starting out, we made some design decisions at the backend. The decision will allow us to independently test the service without interfering with the real application using a term called integration testing. We'll utilize two "dev" packages: reqwest and fake. Dev dependencies only get introduced into your application in development or during testing. In production, they are not included:

Rust allows me to mainly only run the application to confirm things work from a business perspective.

For people starting out building stuff in rust - understand that there is a distinction of async code and libraries and can lead to confusing compiler errors if you don't realize there is a distinction. It's simple in hindsight but did cause me to waste hours barking up the wrong trees at first. Other wise just learn about `match` and Result/Option types asap, they're fundamental.

https://github.com/http-rs/tide tide is great to create an http server / routes

https://github.com/djc/askama I use this to template out HTML and it checks all my boxes, dynamic data, passing in functions, control flow.

https://github.com/launchbadge/sqlx sql interface for a variety of backend, async safe.

https://github.com/seanmonstar/reqwest http client to make requests

Rust is amazing, don't let the initial few speed bumps discourage you - building real things with rust is no more challenging today than any other modern language stack.

Is there any this month in reqwest? I would like to show my interest in https://github.com/seanmonstar/reqwest/issues/39

Reqwest for HTTP connections

It works by fetching a crate's metadata from crates.io, downloading the sources using reqwest, uncompressing them using flate2, extracting them (using tar), and finally rendering a diff (using similar). In the UI you can switch between different versions of the crate to diff against and it also has a search bar to enter the crate name.

I am wondering this, too. Making a request is mostly about one line of code and as you said it is documented and the documentation refers to examples.

Being able to control nondeterminism is particularly useful for testing and debugging. This allows creating reproducible test environments, as well as discrete-event simulation for faster-than-real-time simulation of time delays. For example, Cardano uses a simulation environment for the IO monad that closely follows core Haskell packages; Sui has a simulator based on madsim that provides an API-compatible replacement for the Tokio runtime and intercepts various POSIX API calls in order to enforce determinism. Both allow running the same code in production as in the simulator for testing.

tokio / hyper / toml / serde / serde_json / json5 / console

tokio - An asynchronous runtime for Rust

3. Tokio

The AWS SDK makes use of the async capabilities in the Tokio library. So when you see async in front of a fn that function is capable of executing asynchronously.

Petar is also looking at implementing concurrency the way it is in Go to have a fully functional virtual machine as it is in the spec. This would likely attract more external contributors to developing the VM. One advantage of Rust is that, with the concurrency model, there is already an extensive library called Tokio which he can use. Petar stresses that this isn’t easy, but he believes it’s achievable, at least as a research topic around determinism and concurrency.

Another thing to point out is that async is a thing in Rust. I'm not going to begin to dive into this paradigm in this article, but know it's handled by the awesome Tokio framework.

So I started by using Tokio, a popular async runtime. The docs and samples helped me get a simple outbound TCP connection working. The Rust async book also had a lot of good explanations, both practical and digging into the details of what a runtime does.

Regarding the quote:

> The Original Sin of Rust async programming is making it multi-threaded by default. If premature optimization is the root of all evil, this is the mother of all premature optimizations, and it curses all your code with the unholy Send + 'static, or worse yet Send + Sync + 'static, which just kills all the joy of actually writing Rust.

Agree about the melodramatic tone. I also don't think removing the Send + Sync really makes that big a difference. It's the 'static that bothers me the most. I want scoped concurrency. Something like <https://github.com/tokio-rs/tokio/issues/2596>.

Another thing I really hate about Rust async right now is the poor instrumentation. I'm having a production problem at work right now in which some tasks just get stuck. I wish I could do the equivalent of `gdb; thread apply all bt`. Looking forward to <https://github.com/tokio-rs/tokio/issues/5638> landing at least. It exists right now but is experimental and in my experience sometimes panics. I'm actually writing a PR today to at least use the experimental version on SIGTERM to see what's going on, on the theory that if it crashes oh well, we're shutting down anyway.

Neither of these complaints would be addressed by taking away work stealing. In fact, I could keep doing down my list, and taking away work stealing wouldn't really help with much of anything.

The PHP <-> Rust bindings are provided by https://github.com/Nicelocal/ext-php-rs/ (our fork of https://github.com/davidcole1340/ext-php-rs with a bunch of UX improvements :).

php-tokio's integrates the https://revolt.run event loop with the https://tokio.rs event loop; async functionality is provided by the two event loops, in combination with PHP fibers through revolt's suspension API (I could've directly used the PHP Fiber API to provide coroutine suspension, but it was a tad easier with revolt's suspension API (https://revolt.run/fibers), since it also handles the base case of suspension in the main fiber).