├── public
    ├── robots.txt
    ├── favicon.ico
    ├── logo192.png
    ├── logo512.png
    ├── manifest.json
    └── index.html
├── src
    ├── setupTests.js
    ├── App.test.js
    ├── styles.css
    ├── graphql-operations.js
    ├── App.css
    ├── App.js
    ├── logo.svg
    ├── index.js
    └── serviceWorker.js
├── .gitignore
├── package.json
└── README.md


/public/robots.txt:
--------------------------------------------------------------------------------
1 | # https://www.robotstxt.org/robotstxt.html
2 | User-agent: *
3 | Disallow:
4 | 


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/public/favicon.ico:
--------------------------------------------------------------------------------
https://raw.githubusercontent.com/mongodb-university/realm-graphql-apollo-react/HEAD/public/favicon.ico


--------------------------------------------------------------------------------
/public/logo192.png:
--------------------------------------------------------------------------------
https://raw.githubusercontent.com/mongodb-university/realm-graphql-apollo-react/HEAD/public/logo192.png


--------------------------------------------------------------------------------
/public/logo512.png:
--------------------------------------------------------------------------------
https://raw.githubusercontent.com/mongodb-university/realm-graphql-apollo-react/HEAD/public/logo512.png


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/src/setupTests.js:
--------------------------------------------------------------------------------
1 | // jest-dom adds custom jest matchers for asserting on DOM nodes.
2 | // allows you to do things like:
3 | // expect(element).toHaveTextContent(/react/i)
4 | // learn more: https://github.com/testing-library/jest-dom
5 | import '@testing-library/jest-dom/extend-expect';
6 | 


--------------------------------------------------------------------------------
/src/App.test.js:
--------------------------------------------------------------------------------
 1 | import React from 'react';
 2 | import { render } from '@testing-library/react';
 3 | import App from './App';
 4 | 
 5 | test('renders learn react link', () => {
 6 |   const { getByText } = render(<App />);
 7 |   const linkElement = getByText(/learn react/i);
 8 |   expect(linkElement).toBeInTheDocument();
 9 | });
10 | 


--------------------------------------------------------------------------------
/.gitignore:
--------------------------------------------------------------------------------
 1 | # See https://help.github.com/articles/ignoring-files/ for more about ignoring files.
 2 | 
 3 | # dependencies
 4 | /node_modules
 5 | /.pnp
 6 | .pnp.js
 7 | 
 8 | # testing
 9 | /coverage
10 | 
11 | # production
12 | /build
13 | 
14 | # misc
15 | .DS_Store
16 | .env.local
17 | .env.development.local
18 | .env.test.local
19 | .env.production.local
20 | 
21 | npm-debug.log*
22 | yarn-debug.log*
23 | yarn-error.log*
24 | 


--------------------------------------------------------------------------------
/src/styles.css:
--------------------------------------------------------------------------------
 1 | .App {
 2 |   font-family: sans-serif;
 3 |   text-align: center;
 4 | }
 5 | 
 6 | .subheading {
 7 |   font-style: italic;
 8 |   font-weight: bold;
 9 | }
10 | 
11 | .fancy-input {
12 |   padding: 12px;
13 |   font-size: 1.25rem;
14 | }
15 | 
16 | .fancy-button {
17 |   padding: 12px;
18 |   font-size: 1.25rem;
19 | }
20 | 
21 | .title-input {
22 |   margin-top: 20px;
23 | }
24 | 
25 | .status {
26 |   padding: 20px;
27 | }
28 | 
29 | .important {
30 |   font-size: 24px;
31 |   color: red;
32 | }
33 | 


--------------------------------------------------------------------------------
/src/graphql-operations.js:
--------------------------------------------------------------------------------
 1 | import gql from "graphql-tag";
 2 | 
 3 | export const FIND_MOVIE = gql`
 4 |   query FindMovie($query: MovieQueryInput!) {
 5 |     movie(query: $query) {
 6 |       _id
 7 |       title
 8 |       year
 9 |       runtime
10 |       rated
11 |       poster
12 |     }
13 |   }
14 | `;
15 | 
16 | export const UPDATE_MOVIE = gql`
17 |   mutation UpdateMovie($query: MovieQueryInput!, $set: MovieUpdateInput!) {
18 |     updateOneMovie(query: $query, set: $set) {
19 |       _id
20 |       title
21 |     }
22 |   }
23 | `;
24 | 


--------------------------------------------------------------------------------
/public/manifest.json:
--------------------------------------------------------------------------------
 1 | {
 2 |   "short_name": "React App",
 3 |   "name": "Create React App Sample",
 4 |   "icons": [
 5 |     {
 6 |       "src": "favicon.ico",
 7 |       "sizes": "64x64 32x32 24x24 16x16",
 8 |       "type": "image/x-icon"
 9 |     },
10 |     {
11 |       "src": "logo192.png",
12 |       "type": "image/png",
13 |       "sizes": "192x192"
14 |     },
15 |     {
16 |       "src": "logo512.png",
17 |       "type": "image/png",
18 |       "sizes": "512x512"
19 |     }
20 |   ],
21 |   "start_url": ".",
22 |   "display": "standalone",
23 |   "theme_color": "#000000",
24 |   "background_color": "#ffffff"
25 | }
26 | 


--------------------------------------------------------------------------------
/src/App.css:
--------------------------------------------------------------------------------
 1 | .App {
 2 |   text-align: center;
 3 | }
 4 | 
 5 | .App-logo {
 6 |   height: 40vmin;
 7 |   pointer-events: none;
 8 | }
 9 | 
10 | @media (prefers-reduced-motion: no-preference) {
11 |   .App-logo {
12 |     animation: App-logo-spin infinite 20s linear;
13 |   }
14 | }
15 | 
16 | .App-header {
17 |   background-color: #282c34;
18 |   min-height: 100vh;
19 |   display: flex;
20 |   flex-direction: column;
21 |   align-items: center;
22 |   justify-content: center;
23 |   font-size: calc(10px + 2vmin);
24 |   color: white;
25 | }
26 | 
27 | .App-link {
28 |   color: #61dafb;
29 | }
30 | 
31 | @keyframes App-logo-spin {
32 |   from {
33 |     transform: rotate(0deg);
34 |   }
35 |   to {
36 |     transform: rotate(360deg);
37 |   }
38 | }
39 | 


--------------------------------------------------------------------------------
/package.json:
--------------------------------------------------------------------------------
 1 | {
 2 |   "name": "realm-graphql-apollo-react",
 3 |   "version": "0.1.0",
 4 |   "private": false,
 5 |   "dependencies": {
 6 |     "@apollo/client": "^3.0.2",
 7 |     "@testing-library/jest-dom": "^5.16.5",
 8 |     "@testing-library/react": "^13.4.0",
 9 |     "@testing-library/user-event": "^14.4.3",
10 |     "graphql": "^16.6.0",
11 |     "graphql-tag": "^2.10.4",
12 |     "react": "^18.2.0",
13 |     "react-dom": "^18.2.0",
14 |     "react-scripts": "^5.0.1",
15 |     "realm-web": "^1.2.0"
16 |   },
17 |   "scripts": {
18 |     "start": "react-scripts start",
19 |     "build": "react-scripts build",
20 |     "test": "react-scripts test",
21 |     "eject": "react-scripts eject"
22 |   },
23 |   "eslintConfig": {
24 |     "extends": "react-app"
25 |   },
26 |   "browserslist": {
27 |     "production": [
28 |       ">0.2%",
29 |       "not dead",
30 |       "not op_mini all"
31 |     ],
32 |     "development": [
33 |       "last 1 chrome version",
34 |       "last 1 firefox version",
35 |       "last 1 safari version"
36 |     ]
37 |   }
38 | }
39 | 


--------------------------------------------------------------------------------
/public/index.html:
--------------------------------------------------------------------------------
 1 | <!DOCTYPE html>
 2 | <html lang="en">
 3 |   <head>
 4 |     <meta charset="utf-8" />
 5 |     <link rel="icon" href="%PUBLIC_URL%/favicon.ico" />
 6 |     <meta name="viewport" content="width=device-width, initial-scale=1" />
 7 |     <meta name="theme-color" content="#000000" />
 8 |     <meta
 9 |       name="description"
10 |       content="Web site created using create-react-app"
11 |     />
12 |     <link rel="apple-touch-icon" href="%PUBLIC_URL%/logo192.png" />
13 |     <!--
14 |       manifest.json provides metadata used when your web app is installed on a
15 |       user's mobile device or desktop. See https://developers.google.com/web/fundamentals/web-app-manifest/
16 |     -->
17 |     <link rel="manifest" href="%PUBLIC_URL%/manifest.json" />
18 |     <!--
19 |       Notice the use of %PUBLIC_URL% in the tags above.
20 |       It will be replaced with the URL of the `public` folder during the build.
21 |       Only files inside the `public` folder can be referenced from the HTML.
22 | 
23 |       Unlike "/favicon.ico" or "favicon.ico", "%PUBLIC_URL%/favicon.ico" will
24 |       work correctly both with client-side routing and a non-root public URL.
25 |       Learn how to configure a non-root public URL by running `npm run build`.
26 |     -->
27 |     <title>React App</title>
28 |   </head>
29 |   <body>
30 |     <noscript>You need to enable JavaScript to run this app.</noscript>
31 |     <div id="root"></div>
32 |     <!--
33 |       This HTML file is a template.
34 |       If you open it directly in the browser, you will see an empty page.
35 | 
36 |       You can add webfonts, meta tags, or analytics to this file.
37 |       The build step will place the bundled scripts into the <body> tag.
38 | 
39 |       To begin the development, run `npm start` or `yarn start`.
40 |       To create a production bundle, use `npm run build` or `yarn build`.
41 |     -->
42 |   </body>
43 | </html>
44 | 


--------------------------------------------------------------------------------
/README.md:
--------------------------------------------------------------------------------
 1 | > [!Warning]
 2 | > Atlas App Services has reached its end-of-life status and is no longer actively supported by MongoDB.
 3 | 
 4 | <del>
 5 | 
 6 |    
 7 | # MongoDB Realm GraphQL - Apollo (React)
 8 | 
 9 | This code demonstrates how to connect to your MongoDB Realm app's [GraphQL
10 | API](https://docs.mongodb.com/realm/graphql) from a React application using [Apollo Client
11 | 3](https://www.apollographql.com/docs/react/). For a detailed walkthrough, check out [Use GraphQL
12 | with Apollo Client (React)](https://docs.mongodb.com/realm/web/graphql-apollo-react) in the MongoDB
13 | Realm documentation.
14 | 
15 | ## Set Up
16 | 
17 | 1. Clone the Repository
18 | 
19 |    ```shell
20 |    git clone https://github.com/mongodb-university/realm-graphql-apollo-react
21 |    cd realm-graphql-apollo-react
22 |    ```
23 | 
24 | 2. Install the dependencies
25 | 
26 |    Install the project dependencies with `npm`:
27 |    
28 |    ```shell
29 |    npm install
30 |    ```
31 | 
32 | 3. Load the Sample Data
33 | 
34 |    In MongoDB Atlas, [load the sample datasets into your
35 |    cluster](https://docs.atlas.mongodb.com/sample-data/).
36 | 
37 | 4. Create a MongoDB Realm App
38 | 
39 |    In the same project, [create a new MongoDB Realm
40 |    app](https://docs.mongodb.com/realm/procedures/create-realm-app/). Make sure that the app is
41 |    linked to the cluster that has the sample data.
42 | 
43 | 5. Generate a Schema
44 | 
45 |    Find the `sample_mflix.movies` collection on the Schema screen of the Realm UI and generate a
46 |    schema based on the sample data. When you save the schema, Realm automatically generates
47 |    corresponding GraphQL types.
48 | 
49 | 6. Define Rules
50 | 
51 |    Find the `sample_mflix.movies` collection on the Rules screen of the Realm UI and set the default
52 |    role to have full read and write permission.
53 | 
54 | 7. Enable Anonymous Authentication
55 | 
56 |    This sample app automatically logs in as an anonymous user, so make sure that you enable the
57 |    Anonymous provider.
58 | 
59 | 8. Add Your App ID
60 | 
61 |    [Find your App ID](https://docs.mongodb.com/realm/get-started/find-your-app-id/) and paste it
62 |    into ``src/index.js``.
63 | 
64 | 9.  Run the App
65 | 
66 |    ```shell
67 |    npm run start
68 |    ```
69 | </del>
70 | 


--------------------------------------------------------------------------------
/src/App.js:
--------------------------------------------------------------------------------
 1 | import "./styles.css";
 2 | import * as React from "react";
 3 | import { APP_ID } from "./index";
 4 | import { useQuery, useMutation } from "@apollo/client";
 5 | import { FIND_MOVIE, UPDATE_MOVIE } from "./graphql-operations";
 6 | 
 7 | export default function App(props) {
 8 |   const [searchText, setSearchText] = React.useState("The Matrix Reloaded");
 9 |   const { loading, data } = useQuery(FIND_MOVIE, {
10 |     variables: { query: { title: searchText } }
11 |   });
12 | 
13 |   const movie = data ? data.movie : null;
14 |   const [updateMovie, { loading: updating }] = useMutation(UPDATE_MOVIE);
15 |   const [newTitleText, setNewTitleText] = React.useState("Silly New Title");
16 | 
17 |   const updateMovieTitle = async () => {
18 |     if (!movie) return;
19 |     await updateMovie({
20 |       variables: {
21 |         query: { title: movie.title },
22 |         set: { title: newTitleText }
23 |       }
24 |     });
25 |     setSearchText(newTitleText);
26 |   };
27 | 
28 |   return (
29 |     <div className="App">
30 |       <h1>Find a Movie</h1>
31 |       <span className="subheading">
32 |         The app automatically searches as you type
33 |       </span>
34 |       <div className="title-input">
35 |         <input
36 |           className="fancy-input"
37 |           value={searchText}
38 |           onChange={e => setSearchText(e.target.value)}
39 |           type="text"
40 |         />
41 |       </div>
42 |       {APP_ID === "<Your App ID>" ? (
43 |         <div className="status important">
44 |           Replace APP_ID with your App ID in index.js
45 |         </div>
46 |       ) : (
47 |         !loading &&
48 |         !movie && <div className="status">No movie with that name!</div>
49 |       )}
50 |       {movie && (
51 |         <div>
52 |           {!updating && (
53 |             <div className="title-input">
54 |               <input
55 |                 type="text"
56 |                 className="fancy-input"
57 |                 value={newTitleText}
58 |                 onChange={e => setNewTitleText(e.target.value)}
59 |               />
60 |               <button
61 |                 className="fancy-button"
62 |                 onClick={() => updateMovieTitle()}
63 |               >
64 |                 Change the movie title
65 |               </button>
66 |             </div>
67 |           )}
68 |           <h2>{movie.title}</h2>
69 |           <div>Year: {movie.year}</div>
70 |           <div>Runtime: {movie.runtime} minutes</div>
71 |           <br />
72 |           <img alt={`Poster for ${movie.title}`} src={movie.poster} />
73 |         </div>
74 |       )}
75 |     </div>
76 |   );
77 | }
78 | 


--------------------------------------------------------------------------------
/src/logo.svg:
--------------------------------------------------------------------------------
1 | <svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 841.9 595.3">
2 |     <g fill="#61DAFB">
3 |         <path d="M666.3 296.5c0-32.5-40.7-63.3-103.1-82.4 14.4-63.6 8-114.2-20.2-130.4-6.5-3.8-14.1-5.6-22.4-5.6v22.3c4.6 0 8.3.9 11.4 2.6 13.6 7.8 19.5 37.5 14.9 75.7-1.1 9.4-2.9 19.3-5.1 29.4-19.6-4.8-41-8.5-63.5-10.9-13.5-18.5-27.5-35.3-41.6-50 32.6-30.3 63.2-46.9 84-46.9V78c-27.5 0-63.5 19.6-99.9 53.6-36.4-33.8-72.4-53.2-99.9-53.2v22.3c20.7 0 51.4 16.5 84 46.6-14 14.7-28 31.4-41.3 49.9-22.6 2.4-44 6.1-63.6 11-2.3-10-4-19.7-5.2-29-4.7-38.2 1.1-67.9 14.6-75.8 3-1.8 6.9-2.6 11.5-2.6V78.5c-8.4 0-16 1.8-22.6 5.6-28.1 16.2-34.4 66.7-19.9 130.1-62.2 19.2-102.7 49.9-102.7 82.3 0 32.5 40.7 63.3 103.1 82.4-14.4 63.6-8 114.2 20.2 130.4 6.5 3.8 14.1 5.6 22.5 5.6 27.5 0 63.5-19.6 99.9-53.6 36.4 33.8 72.4 53.2 99.9 53.2 8.4 0 16-1.8 22.6-5.6 28.1-16.2 34.4-66.7 19.9-130.1 62-19.1 102.5-49.9 102.5-82.3zm-130.2-66.7c-3.7 12.9-8.3 26.2-13.5 39.5-4.1-8-8.4-16-13.1-24-4.6-8-9.5-15.8-14.4-23.4 14.2 2.1 27.9 4.7 41 7.9zm-45.8 106.5c-7.8 13.5-15.8 26.3-24.1 38.2-14.9 1.3-30 2-45.2 2-15.1 0-30.2-.7-45-1.9-8.3-11.9-16.4-24.6-24.2-38-7.6-13.1-14.5-26.4-20.8-39.8 6.2-13.4 13.2-26.8 20.7-39.9 7.8-13.5 15.8-26.3 24.1-38.2 14.9-1.3 30-2 45.2-2 15.1 0 30.2.7 45 1.9 8.3 11.9 16.4 24.6 24.2 38 7.6 13.1 14.5 26.4 20.8 39.8-6.3 13.4-13.2 26.8-20.7 39.9zm32.3-13c5.4 13.4 10 26.8 13.8 39.8-13.1 3.2-26.9 5.9-41.2 8 4.9-7.7 9.8-15.6 14.4-23.7 4.6-8 8.9-16.1 13-24.1zM421.2 430c-9.3-9.6-18.6-20.3-27.8-32 9 .4 18.2.7 27.5.7 9.4 0 18.7-.2 27.8-.7-9 11.7-18.3 22.4-27.5 32zm-74.4-58.9c-14.2-2.1-27.9-4.7-41-7.9 3.7-12.9 8.3-26.2 13.5-39.5 4.1 8 8.4 16 13.1 24 4.7 8 9.5 15.8 14.4 23.4zM420.7 163c9.3 9.6 18.6 20.3 27.8 32-9-.4-18.2-.7-27.5-.7-9.4 0-18.7.2-27.8.7 9-11.7 18.3-22.4 27.5-32zm-74 58.9c-4.9 7.7-9.8 15.6-14.4 23.7-4.6 8-8.9 16-13 24-5.4-13.4-10-26.8-13.8-39.8 13.1-3.1 26.9-5.8 41.2-7.9zm-90.5 125.2c-35.4-15.1-58.3-34.9-58.3-50.6 0-15.7 22.9-35.6 58.3-50.6 8.6-3.7 18-7 27.7-10.1 5.7 19.6 13.2 40 22.5 60.9-9.2 20.8-16.6 41.1-22.2 60.6-9.9-3.1-19.3-6.5-28-10.2zM310 490c-13.6-7.8-19.5-37.5-14.9-75.7 1.1-9.4 2.9-19.3 5.1-29.4 19.6 4.8 41 8.5 63.5 10.9 13.5 18.5 27.5 35.3 41.6 50-32.6 30.3-63.2 46.9-84 46.9-4.5-.1-8.3-1-11.3-2.7zm237.2-76.2c4.7 38.2-1.1 67.9-14.6 75.8-3 1.8-6.9 2.6-11.5 2.6-20.7 0-51.4-16.5-84-46.6 14-14.7 28-31.4 41.3-49.9 22.6-2.4 44-6.1 63.6-11 2.3 10.1 4.1 19.8 5.2 29.1zm38.5-66.7c-8.6 3.7-18 7-27.7 10.1-5.7-19.6-13.2-40-22.5-60.9 9.2-20.8 16.6-41.1 22.2-60.6 9.9 3.1 19.3 6.5 28.1 10.2 35.4 15.1 58.3 34.9 58.3 50.6-.1 15.7-23 35.6-58.4 50.6zM320.8 78.4z"/>
4 |         <circle cx="420.9" cy="296.5" r="45.7"/>
5 |         <path d="M520.5 78.1z"/>
6 |     </g>
7 | </svg>
8 | 


--------------------------------------------------------------------------------
/src/index.js:
--------------------------------------------------------------------------------
 1 | // React
 2 | import React from "react";
 3 | import { createRoot } from "react-dom/client";
 4 | // Apollo
 5 | import {
 6 |   ApolloProvider,
 7 |   ApolloClient,
 8 |   HttpLink,
 9 |   InMemoryCache,
10 | } from "@apollo/client";
11 | // Realm
12 | import * as Realm from "realm-web";
13 | // Check out app.js for examples of how to run GraphQL operations
14 | import App from "./App";
15 | 
16 | // To set up your app:
17 | //
18 | // 1. Link a cluster that includes the MongoDB Atlas sample data sets
19 | // 2. Configure permissions for the ``sample_mflix.movies`` collection. For this
20 | //    demo, you can assign full read/write permissions to the default role.
21 | // 3. Generate a collection schema for the ``sample_mflix.movies`` collection.
22 | // 4. Enable anonymous authentication
23 | // 5. Deploy your changes
24 | //
25 | // Once your app is set up, replace the value of APP_ID with your App ID
26 | export const APP_ID = "<Your App ID>";
27 | 
28 | // Connect to your MongoDB Realm app
29 | const app = new Realm.App(APP_ID);
30 | 
31 | // Gets a valid Realm user access token to authenticate requests
32 | async function getValidAccessToken() {
33 |   // Guarantee that there's a logged in user with a valid access token
34 |   if (!app.currentUser) {
35 |     // If no user is logged in, log in an anonymous user. The logged in user will have a valid
36 |     // access token.
37 |     await app.logIn(Realm.Credentials.anonymous());
38 |   } else {
39 |     // An already logged in user's access token might be stale. To guarantee that the token is
40 |     // valid, we refresh the user's custom data which also refreshes their access token.
41 |     await app.currentUser.refreshCustomData();
42 |   }
43 |   
44 |   return app.currentUser.accessToken;
45 | }
46 | 
47 | // Configure the ApolloClient to connect to your app's GraphQL endpoint
48 | const client = new ApolloClient({
49 |   link: new HttpLink({
50 |     uri: `https://realm.mongodb.com/api/client/v2.0/app/${APP_ID}/graphql`,
51 |     // We define a custom fetch handler for the Apollo client that lets us authenticate GraphQL requests.
52 |     // The function intercepts every Apollo HTTP request and adds an Authorization header with a valid
53 |     // access token before sending the request.
54 |     fetch: async (uri, options) => {
55 |       const accessToken = await getValidAccessToken();
56 |       options.headers.Authorization = `Bearer ${accessToken}`;
57 |       return fetch(uri, options);
58 |     },
59 |   }),
60 |   cache: new InMemoryCache(),
61 | });
62 | 
63 | // Wrap your app with an ApolloProvider that provides the client
64 | createRoot(document.getElementById("root")).render(
65 |   <ApolloProvider client={client}>
66 |     <App />
67 |   </ApolloProvider>,
68 | );
69 | 


--------------------------------------------------------------------------------
/src/serviceWorker.js:
--------------------------------------------------------------------------------
  1 | // This optional code is used to register a service worker.
  2 | // register() is not called by default.
  3 | 
  4 | // This lets the app load faster on subsequent visits in production, and gives
  5 | // it offline capabilities. However, it also means that developers (and users)
  6 | // will only see deployed updates on subsequent visits to a page, after all the
  7 | // existing tabs open on the page have been closed, since previously cached
  8 | // resources are updated in the background.
  9 | 
 10 | // To learn more about the benefits of this model and instructions on how to
 11 | // opt-in, read https://bit.ly/CRA-PWA
 12 | 
 13 | const isLocalhost = Boolean(
 14 |   window.location.hostname === 'localhost' ||
 15 |     // [::1] is the IPv6 localhost address.
 16 |     window.location.hostname === '[::1]' ||
 17 |     // 127.0.0.0/8 are considered localhost for IPv4.
 18 |     window.location.hostname.match(
 19 |       /^127(?:\.(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)){3}$/
 20 |     )
 21 | );
 22 | 
 23 | export function register(config) {
 24 |   if (process.env.NODE_ENV === 'production' && 'serviceWorker' in navigator) {
 25 |     // The URL constructor is available in all browsers that support SW.
 26 |     const publicUrl = new URL(process.env.PUBLIC_URL, window.location.href);
 27 |     if (publicUrl.origin !== window.location.origin) {
 28 |       // Our service worker won't work if PUBLIC_URL is on a different origin
 29 |       // from what our page is served on. This might happen if a CDN is used to
 30 |       // serve assets; see https://github.com/facebook/create-react-app/issues/2374
 31 |       return;
 32 |     }
 33 | 
 34 |     window.addEventListener('load', () => {
 35 |       const swUrl = `${process.env.PUBLIC_URL}/service-worker.js`;
 36 | 
 37 |       if (isLocalhost) {
 38 |         // This is running on localhost. Let's check if a service worker still exists or not.
 39 |         checkValidServiceWorker(swUrl, config);
 40 | 
 41 |         // Add some additional logging to localhost, pointing developers to the
 42 |         // service worker/PWA documentation.
 43 |         navigator.serviceWorker.ready.then(() => {
 44 |           console.log(
 45 |             'This web app is being served cache-first by a service ' +
 46 |               'worker. To learn more, visit https://bit.ly/CRA-PWA'
 47 |           );
 48 |         });
 49 |       } else {
 50 |         // Is not localhost. Just register service worker
 51 |         registerValidSW(swUrl, config);
 52 |       }
 53 |     });
 54 |   }
 55 | }
 56 | 
 57 | function registerValidSW(swUrl, config) {
 58 |   navigator.serviceWorker
 59 |     .register(swUrl)
 60 |     .then(registration => {
 61 |       registration.onupdatefound = () => {
 62 |         const installingWorker = registration.installing;
 63 |         if (installingWorker == null) {
 64 |           return;
 65 |         }
 66 |         installingWorker.onstatechange = () => {
 67 |           if (installingWorker.state === 'installed') {
 68 |             if (navigator.serviceWorker.controller) {
 69 |               // At this point, the updated precached content has been fetched,
 70 |               // but the previous service worker will still serve the older
 71 |               // content until all client tabs are closed.
 72 |               console.log(
 73 |                 'New content is available and will be used when all ' +
 74 |                   'tabs for this page are closed. See https://bit.ly/CRA-PWA.'
 75 |               );
 76 | 
 77 |               // Execute callback
 78 |               if (config && config.onUpdate) {
 79 |                 config.onUpdate(registration);
 80 |               }
 81 |             } else {
 82 |               // At this point, everything has been precached.
 83 |               // It's the perfect time to display a
 84 |               // "Content is cached for offline use." message.
 85 |               console.log('Content is cached for offline use.');
 86 | 
 87 |               // Execute callback
 88 |               if (config && config.onSuccess) {
 89 |                 config.onSuccess(registration);
 90 |               }
 91 |             }
 92 |           }
 93 |         };
 94 |       };
 95 |     })
 96 |     .catch(error => {
 97 |       console.error('Error during service worker registration:', error);
 98 |     });
 99 | }
100 | 
101 | function checkValidServiceWorker(swUrl, config) {
102 |   // Check if the service worker can be found. If it can't reload the page.
103 |   fetch(swUrl, {
104 |     headers: { 'Service-Worker': 'script' },
105 |   })
106 |     .then(response => {
107 |       // Ensure service worker exists, and that we really are getting a JS file.
108 |       const contentType = response.headers.get('content-type');
109 |       if (
110 |         response.status === 404 ||
111 |         (contentType != null && contentType.indexOf('javascript') === -1)
112 |       ) {
113 |         // No service worker found. Probably a different app. Reload the page.
114 |         navigator.serviceWorker.ready.then(registration => {
115 |           registration.unregister().then(() => {
116 |             window.location.reload();
117 |           });
118 |         });
119 |       } else {
120 |         // Service worker found. Proceed as normal.
121 |         registerValidSW(swUrl, config);
122 |       }
123 |     })
124 |     .catch(() => {
125 |       console.log(
126 |         'No internet connection found. App is running in offline mode.'
127 |       );
128 |     });
129 | }
130 | 
131 | export function unregister() {
132 |   if ('serviceWorker' in navigator) {
133 |     navigator.serviceWorker.ready
134 |       .then(registration => {
135 |         registration.unregister();
136 |       })
137 |       .catch(error => {
138 |         console.error(error.message);
139 |       });
140 |   }
141 | }
142 | 


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