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Comment by ksenzee | Hacker News Reader

Shouldn't an HTTP request library make async available? HTTP is the textbook example for async.

It should, but it shouldn't be the default. Right now, reqwest is the default HTTP request library in Rust ecosystem, and async is mandatory for reqwest. This is a bad situation to be in.

> async is mandatory for reqwest

async is not mandatory for reqwest. It provides a blocking API as well.

> reqwest is the default HTTP request library in Rust ecosystem

There is no "default" libraries. There are popular HTTP clients other than reqwest that also provide blocking APIs such as isahc and ureq

reqwest provides a blocking API, but reqwest also always depends on Tokio. A blocking API doesn't help when I don't want Tokio in my dependency tree at all.

I am using isahc, but that also doesn't help when (say) Rusoto AWS library pulls reqwest pulls Tokio pulls async.

Doesn't sound like a problem with async, just sounds like you disagreeing about what good deps for your deps are.

Can you explain exactly what that library using Tokio internally exposes to you that's a problem? Because, as written, this sounds like a religious argument.

If you need to use (for the sake of the example) Rusoto, since it is based on tokio, you'll need to set up the Tokio executor or at least add a macro to your main for this to be done for you. I believe Rusoto actually would take care of this for you if you haven't done it yourself however friction arises when you were already using a different version of tokio and Rusoto is built against another.

Basically, it isn't entirely opaque to you how it is handled.

Gotcha, makes sense. Thanks!

I had a simple rust program that used reqwest -- it just pulled down a few web pages and parsed some data out of tables in the HTML. At the time reqwest had a simple synchronous API function that made this easy. The version of reqwest which added async support broke compatibility of that function and didn't appear to provide any similarly easy to use equivalent. Luckily my use-case went away (the website I was screen scraping died) so I didn't need to try to actually fix my program to work with newer reqwest versions. But it left a pretty sour taste regarding async...

Req west? The best.

There's ureq for sync/blocking HTTP requests.

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