React 配置跨域

1. 在项目根目录下，安装 http-proxy-middleware

yarn add http-proxy-middleware

2. 在src文件目录下新建一个setupProxy.js

代码如下

const { createProxyMiddleware } = require("http-proxy-middleware");
module.exports = function (app) {
  app.use(
    "/api",
    createProxyMiddleware({
      target: "http://localhost:8080",
      changeOrigin: true,
      pathRewrite: { "^/api": "" },
    })
  );
};

3. 修改发送请求的url

由原来的 http://localhost:8080/user

改为 /api/user

    const res = await fetch("/api/user", {
        ...
    });