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1'use strict';
2
3const errorOverlayMiddleware = require('react-dev-utils/errorOverlayMiddleware');
4const noopServiceWorkerMiddleware = require('react-dev-utils/noopServiceWorkerMiddleware');
5const ignoredFiles = require('react-dev-utils/ignoredFiles');
6const config = require('./webpack.config.dev');
7const paths = require('./paths');
8
9const protocol = process.env.HTTPS === 'true' ? 'https' : 'http';
10const host = process.env.HOST || '0.0.0.0';
11
12module.exports = function(proxy, allowedHost) {
13 return {
14 // WebpackDevServer 2.4.3 introduced a security fix that prevents remote
15 // websites from potentially accessing local content through DNS rebinding:
16 // https://github.com/webpack/webpack-dev-server/issues/887
17 // https://medium.com/webpack/webpack-dev-server-middleware-security-issues-1489d950874a
18 // However, it made several existing use cases such as development in cloud
19 // environment or subdomains in development significantly more complicated:
20 // https://github.com/facebookincubator/create-react-app/issues/2271
21 // https://github.com/facebookincubator/create-react-app/issues/2233
22 // While we're investigating better solutions, for now we will take a
23 // compromise. Since our WDS configuration only serves files in the `public`
24 // folder we won't consider accessing them a vulnerability. However, if you
25 // use the `proxy` feature, it gets more dangerous because it can expose
26 // remote code execution vulnerabilities in backends like Django and Rails.
27 // So we will disable the host check normally, but enable it if you have
28 // specified the `proxy` setting. Finally, we let you override it if you
29 // really know what you're doing with a special environment variable.
30 disableHostCheck:
31 !proxy || process.env.DANGEROUSLY_DISABLE_HOST_CHECK === 'true',
32 // Enable gzip compression of generated files.
33 compress: true,
34 // Silence WebpackDevServer's own logs since they're generally not useful.
35 // It will still show compile warnings and errors with this setting.
36 clientLogLevel: 'none',
37 // By default WebpackDevServer serves physical files from current directory
38 // in addition to all the virtual build products that it serves from memory.
39 // This is confusing because those files won’t automatically be available in
40 // production build folder unless we copy them. However, copying the whole
41 // project directory is dangerous because we may expose sensitive files.
42 // Instead, we establish a convention that only files in `public` directory
43 // get served. Our build script will copy `public` into the `build` folder.
44 // In `index.html`, you can get URL of `public` folder with %PUBLIC_URL%:
45 // <link rel="shortcut icon" href="%PUBLIC_URL%/favicon.ico">
46 // In JavaScript code, you can access it with `process.env.PUBLIC_URL`.
47 // Note that we only recommend to use `public` folder as an escape hatch
48 // for files like `favicon.ico`, `manifest.json`, and libraries that are
49 // for some reason broken when imported through Webpack. If you just want to
50 // use an image, put it in `src` and `import` it from JavaScript instead.
51 contentBase: paths.appPublic,
52 // By default files from `contentBase` will not trigger a page reload.
53 watchContentBase: true,
54 // Enable hot reloading server. It will provide /sockjs-node/ endpoint
55 // for the WebpackDevServer client so it can learn when the files were
56 // updated. The WebpackDevServer client is included as an entry point
57 // in the Webpack development configuration. Note that only changes
58 // to CSS are currently hot reloaded. JS changes will refresh the browser.
59 hot: true,
60 // It is important to tell WebpackDevServer to use the same "root" path
61 // as we specified in the config. In development, we always serve from /.
62 publicPath: config.output.publicPath,
63 // WebpackDevServer is noisy by default so we emit custom message instead
64 // by listening to the compiler events with `compiler.plugin` calls above.
65 quiet: true,
66 // Reportedly, this avoids CPU overload on some systems.
67 // https://github.com/facebookincubator/create-react-app/issues/293
68 // src/node_modules is not ignored to support absolute imports
69 // https://github.com/facebookincubator/create-react-app/issues/1065
70 watchOptions: {
71 ignored: ignoredFiles(paths.appSrc),
72 },
73 // Enable HTTPS if the HTTPS environment variable is set to 'true'
74 https: protocol === 'https',
75 host: host,
76 overlay: false,
77 historyApiFallback: {
78 // Paths with dots should still use the history fallback.
79 // See https://github.com/facebookincubator/create-react-app/issues/387.
80 disableDotRule: true,
81 },
82 public: allowedHost,
83 proxy,
84 before(app) {
85 // This lets us open files from the runtime error overlay.
86 app.use(errorOverlayMiddleware());
87 // This service worker file is effectively a 'no-op' that will reset any
88 // previous service worker registered for the same host:port combination.
89 // We do this in development to avoid hitting the production cache if
90 // it used the same host and port.
91 // https://github.com/facebookincubator/create-react-app/issues/2272#issuecomment-302832432
92 app.use(noopServiceWorkerMiddleware());
93 },
94 };
95};