How can I get JSON from the Github API?

Question

I just want to get a JSON from the following URL.

So I used this code:

extern crate reqwest;

fn main() -> Result<(), Box<dyn std::error::Error>> {
    let res = reqwest::Client::new()
        .get("https://api.github.com/users/octocat")
        .send()?
        .text()?;
    println!("{}", res);

    Ok(())
}

But I don't know how to solve the error :

error[E0277]: the `?` operator can only be applied to values that implement `std::ops::Try`
  --> src\main.rs:19:15
   |
19 |       let res = reqwest::Client::new()
   |  _______________^
20 | |         .get("https://api.github.com/users/octocat")
21 | |         .send()?
   | |________________^ the `?` operator cannot be applied to type `impl std::future::Future`
   |
   = help: the trait `std::ops::Try` is not implemented for `impl std::future::Future`
   = note: required by `std::ops::Try::into_result`

error: aborting due to previous error

For more information about this error, try `rustc --explain E0277`.
error: could not compile `Desktop`.

but I can also obtain what I want with a simple

curl https://api.github.com/users/octocat

I've tried to add use std::ops::Try; but it doesn't work better.

Does this answer your question? [How do I synchronously return a value calculated in an asynchronous Future in stable Rust?](https://stackoverflow.com/questions/52521201/how-do-i-synchronously-return-a-value-calculated-in-an-asynchronous-future-in-st) — E_net4, Nov 03 '20 at 16:29
The method `.send` in this version of reqwest is asynchronous. It returns a future, which needs to be executed to completion. Follow the [documentation for reqwest](https://docs.rs/reqwest/0.10.8/reqwest/) for a working example. — E_net4, Nov 03 '20 at 16:32

Ibraheem Ahmed · Accepted Answer · 2021-08-16T15:02:50.637

The reqwest crate uprovides an asynchronous api by default. Therefore you have to .await before handling the error with the ? operator. You also have to use an async runtime, such as tokio:

#[tokio::main]
async fn main() -> Result<(), Box<dyn std::error::Error>> {
  let resp = reqwest::Client::new()
    .get("https://api.github.com/users/octocat")
    .send()
    .await?
    .json::<std::collections::HashMap<String, String>>()
    .await?;
  println!("{:#?}", resp);
  Ok(())
}

Note that to use convert the response to json as shown above, you must enable the json feature in your Cargo.toml:

reqwest = { version = "0.10.8", features = ["json"] }

If you don't want to use an async runtime, you can enable the blocking reqwest client:

[dependencies]
reqwest = { version = "0.10", features = ["blocking", "json"] }

And use it like so:

fn main() -> Result<(), Box<dyn std::error::Error>> {
  let resp = reqwest::blocking::Client::new()
    .get("https://api.github.com/users/octocat")
    .send()?
    .json::<std::collections::HashMap<String, String>>()?;
  println!("{:#?}", resp);
  Ok(())
}

Github's api requires a couple other config options. Here is a minimal working example with reqwest and the github api:

use reqwest::header::{HeaderMap, HeaderValue, USER_AGENT};
use serde::{Deserialize};

fn main() -> Result<(), Box<dyn std::error::Error>> {
  let mut headers = HeaderMap::new();
  // add the user-agent header required by github
  headers.insert(USER_AGENT, HeaderValue::from_static("reqwest"));

  let resp = reqwest::blocking::Client::new()
    .get("https://api.github.com/users/octocat")
    .headers(headers)
    .send()?
    .json::<GithubUser>()?;
  println!("{:#?}", resp);
  Ok(())
}

// Note that there are many other fields
// that are not included for this example
#[derive(Deserialize, Debug)]
pub struct GithubUser {
  login: String,
  id: usize,
  url: String,
  #[serde(rename = "type")]
  ty: String,
  name: String,
  followers: usize
}

I obtain a warning and a Error : warning: crate `Desktop` should have a snake case name | = note: `#[warn(non_snake_case)]` on by default = help: convert the identifier to snake case: `desktop` Error: reqwest::Error { kind: Decode, source: Error("expected value", line: 2, column: 1) } And it compile ! But I don't have my json ... I tried to use #[warn(non_snake_case)] But nothing change — Wolodia ZDETOVETZKY, Nov 03 '20 at 16:50
And I add use std::collections::HashMap; in your code to work — Wolodia ZDETOVETZKY, Nov 03 '20 at 16:51
The error you are receiving `Error(expected value)` does not have anything to do with `reqwest`. Convert the request with `.text()` instead of `.json()` an error returned by the github api: `Request forbidden by administrative rules.` — Ibraheem Ahmed, Nov 03 '20 at 17:15

How can I get JSON from the Github API?

1 Answers1