45 lines
1.1 KiB
Rust
45 lines
1.1 KiB
Rust
#![deny(warnings)]
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extern crate hyper;
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#[macro_use]
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extern crate serde_derive;
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extern crate serde;
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extern crate serde_json;
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use hyper::Client;
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use futures_util::TryStreamExt;
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// A simple type alias so as to DRY.
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type Result<T> = std::result::Result<T, Box<dyn std::error::Error + Send + Sync>>;
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#[tokio::main]
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async fn main() -> Result<()> {
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let url = "http://jsonplaceholder.typicode.com/users".parse().unwrap();
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let users = fetch_json(url).await?;
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// print users
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println!("users: {:#?}", users);
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// print the sum of ids
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let sum = users.iter().fold(0, |acc, user| acc + user.id);
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println!("sum of ids: {}", sum);
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Ok(())
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}
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async fn fetch_json(url: hyper::Uri) -> Result<Vec<User>> {
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let client = Client::new();
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// Fetch the url...
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let res = client.get(url).await?;
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// asynchronously concatenate chunks of the body
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let body = res.into_body().try_concat().await?;
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// try to parse as json with serde_json
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let users = serde_json::from_slice(&body)?;
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Ok(users)
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}
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#[derive(Deserialize, Debug)]
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struct User {
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id: i32,
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name: String,
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}
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