我想编写一个从 Rust 后端获取数据的网页。然而，我从后端得到的是一些随机的 HTML 文本。如何将数据（例如一些简短的纯文本）从后端传输到前端？
下面是我的前端代码：
import {useState} from 'react';
import './App.css';
import Container from 'react-bootstrap/Container';
import Row from 'react-bootstrap/Row';
import Button from 'react-bootstrap/Button';
function App() {
const [buttonText, setButtonText] = useState();
function handleClick() {
const req = new Request("127.0.0.1:3003", {method: 'GET'})
const headers = new Headers([["Content-Type", "plain/text"]])
fetch(req, headers).then(response =>
response.text()
).then(response =>
setButtonText(response)
).catch(err =>
alert(err)
)
}
return (
<div className="App">
<Container>
<Row>
<Button size="lg" onClick={handleClick}>fetch</Button>
<div>{buttonText}</div>
</Row>
</Container>
</div>
);
}
export default App;
Rust 后端代码：
use std::net::SocketAddr;
use axum::{
routing::get,
Router,
};
#[tokio::main]
async fn main() {
// build our application with a single route
let app = Router::new().route("/", get(|| async { "Hello, world" }));
// run it with hyper on localhost:3003
axum::Server::bind(&SocketAddr::from(([127, 0, 0, 1], 3003)))
.serve(app.into_make_service())
.await
.unwrap();
}
我假设的文本内容是：
Hello, world!
它实际上是什么：
<!DOCTYPE html> <html lang="en"> <head> <meta charset="utf-8" /> <link rel="icon" href="/favicon.ico" /> <meta name="viewport" content="width=device-width, initial-scale=1" /> <meta name="theme-color" content="#000000" /> <meta name="description" content="Web site created using create-react-app" /> <link rel="apple-touch-icon" href="/logo192.png" /> <!-- manifest.json provides metadata used when your web app is installed on a user's mobile device or desktop. See https://developers.google.com/web/fundamentals/web-app-manifest/ --> <link rel="manifest" href="/manifest.json" /> <!-- Notice the use of in the tags above. It will be replaced with the URL of the `public` folder during the build. Only files inside the `public` folder can be referenced from the HTML. Unlike "/favicon.ico" or "favicon.ico", "/favicon.ico" will work correctly both with client-side routing and a non-root public URL. Learn how to configure a non-root public URL by running `npm run build`. --> <title>React App</title> <script defer src="/static/js/bundle.js"></script></head> <body> <noscript>You need to enable JavaScript to run this app.</noscript> <div id="root"></div> <!-- This HTML file is a template. If you open it directly in the browser, you will see an empty page. You can add webfonts, meta tags, or analytics to this file. The build step will place the bundled scripts into the <body> tag. To begin the development, run `npm start` or `yarn start`. To create a production bundle, use `npm run build` or `yarn build`. --> </body> </html>
问题确实是CORS。下面是有效的代码。
前端：
import {useState} from 'react';
import './App.css';
import Container from 'react-bootstrap/Container';
import Row from 'react-bootstrap/Row';
import Button from 'react-bootstrap/Button';
function App() {
const [buttonText, setButtonText] = useState();
function handleClick() {
const req = new Request("http://127.0.0.1:3003", {method: 'GET'})
fetch(req).then(response =>
response.text()
).then(response =>
setButtonText(response)
).catch(err =>
alert(err)
)
}
return (
<div className="App">
<Container>
<Row>
<Button size="lg" onClick={handleClick}>fetch</Button>
<div>{buttonText}</div>
</Row>
</Container>
</div>
);
}
export default App;
后端：
use std::net::SocketAddr;
use http::Method;
use axum::{
routing::get,
Router,
};
use tower_http::cors::{Any, CorsLayer};
#[tokio::main]
async fn main() {
let cors = CorsLayer::new().allow_methods([Method::GET, Method::POST]).allow_origin(Any);
let app = Router::new().route("/", get(|| async { "Hello, world" }));
let app = app.layer(cors);
axum::Server::bind(&SocketAddr::from(([127, 0, 0, 1], 3003)))
.serve(app.into_make_service())
.await
.unwrap();
}