remix-run · kentcdodds · Mar 9, 2022 · Feb 28, 2022 · Feb 28, 2022 · Feb 28, 2022
diff --git a/examples/msw/.gitignore b/examples/msw/.gitignore
@@ -0,0 +1,5 @@
+node_modules
+
+/.cache
+/build
+/public/build
diff --git a/examples/msw/README.md b/examples/msw/README.md
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+# Remix + MSW
+
+This example demonstrates [MSW's][msw] usage with Remix to mock any HTTP calls from the Remix server during development.
+
+## Preview
+
+Open this example on [CodeSandbox](https://codesandbox.com):
+
+[![Open in CodeSandbox](https://codesandbox.io/static/img/play-codesandbox.svg)](https://codesandbox.io/s/github/remix-run/remix/tree/main/examples/msw)
+
+## Example
+
+- If the API is still under development and we don't want to wait for the API to be completed.
+- We want to simulate various edge and error cases of making an HTTP call and check how the app handles these cases.
+- If the external APIs are metered and charged for the number of API calls made, it's pretty easy to burst through the API quota during development.
+- We need an active network during development if we rely on external HTTP calls for the app to work. For some, this may be an issue.
+
+We can mock the HTTP calls using MSW, which intercepts the API calls from the server and returns a mocked response.
+
+You can read more about the use cases of MSW [here](https://mswjs.io/docs/#when-to-mock-api)
+
+## Gotchas
+
+MSW currently does not support intercepting requests made by [undici](https://undici.nodejs.org/#/). For local development, Cloudflare Workers and Pages simulates the production environment using [wrangler](https://developers.cloudflare.com/workers/cli-wrangler), which intern runs [miniflare](https://github.com/cloudflare/miniflare). `Miniflare` implements `fetch` using `undici` instead of `node-fetch`. You can follow this issue [#159](https://github.com/mswjs/interceptors/issues/159) to track the progress.
+
+## Relevant files
+
+- [mocks](./mocks/index.js) - registers the Node HTTP mock server
+- [handlers](./mocks/handlers.js) - describes the HTTP mocks
+- [root](./app/root.tsx)
+- [package.json](./package.json)
+
+## Related Links
+
+[MSW][msw]
+
+[msw]: https://mswjs.io/
diff --git a/examples/msw/app/entry.client.tsx b/examples/msw/app/entry.client.tsx
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+import { hydrate } from "react-dom";
+import { RemixBrowser } from "remix";
+
+hydrate(<RemixBrowser />, document);
diff --git a/examples/msw/app/entry.server.tsx b/examples/msw/app/entry.server.tsx
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+import { renderToString } from "react-dom/server";
+import { RemixServer } from "remix";
+import type { EntryContext } from "remix";
+
+export default function handleRequest(
+  request: Request,
+  responseStatusCode: number,
+  responseHeaders: Headers,
+  remixContext: EntryContext
+) {
+  const markup = renderToString(
+    <RemixServer context={remixContext} url={request.url} />
+  );
+
+  responseHeaders.set("Content-Type", "text/html");
+
+  return new Response("<!DOCTYPE html>" + markup, {
+    status: responseStatusCode,
+    headers: responseHeaders,
+  });
+}
diff --git a/examples/msw/app/root.tsx b/examples/msw/app/root.tsx
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+import type { LoaderFunction } from "remix";
+import { useLoaderData } from "remix";
+import { json } from "remix";
+import { Links, LiveReload, Meta, Scripts, ScrollRestoration } from "remix";
+
+type LoaderData = { message: string };
+
+export const loader: LoaderFunction = async () => {
+  const data = await fetch("https://my-mock-api.com").then((response) =>
+    response.json()
+  );
+
+  if (!data || typeof data.message !== "string") {
+    throw json({ message: "Server error" }, { status: 500 });
+  }
+
+  return json<LoaderData>(data);
+};
+
+export default function App() {
+  const loaderData = useLoaderData<LoaderData>();
+
+  return (
+    <html lang="en">
+      <head>
+        <meta charSet="utf-8" />
+        <meta name="viewport" content="width=device-width,initial-scale=1" />
+        <Meta />
+        <Links />
+      </head>
+      <body>
+        <h1>{loaderData.message}</h1>
+        <ScrollRestoration />
+        <Scripts />
+        <LiveReload />
+      </body>
+    </html>
+  );
+}
diff --git a/examples/msw/mocks/handlers.js b/examples/msw/mocks/handlers.js
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+const { rest } = require("msw");
+
+const handlers = [
+  rest.get("https://my-mock-api.com", (_, res, ctx) => {
+    return res(ctx.status(200), ctx.json({ message: "from msw" }));
+  }),
+];
+
+module.exports = handlers;
diff --git a/examples/msw/mocks/index.js b/examples/msw/mocks/index.js
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+const { setupServer } = require("msw/node");
+const handlers = require("./handlers");
+
+const server = setupServer(...handlers);
+server.listen({ onUnhandledRequest: "warn" });
+console.info("MSW initialised");