├── src
    ├── app.JPG
    ├── index.css
    ├── App.test.js
    ├── index.js
    ├── Note
    │   ├── Note.css
    │   └── Note.jsx
    ├── NoteForm
    │   ├── NoteForm.css
    │   └── NoteForm.jsx
    ├── App.css
    ├── App.js
    ├── logo.svg
    └── registerServiceWorker.js
├── public
    ├── favicon.ico
    ├── manifest.json
    └── index.html
├── package.json
├── .gitignore
├── README.md
└── LICENSE


/src/app.JPG:
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https://raw.githubusercontent.com/wesdoyle/react-firebase-notes-app/HEAD/src/app.JPG


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/src/index.css:
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1 | @import url('https://fonts.googleapis.com/css?family=Lato|Permanent+Marker');


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/public/favicon.ico:
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https://raw.githubusercontent.com/wesdoyle/react-firebase-notes-app/HEAD/public/favicon.ico


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/src/App.test.js:
--------------------------------------------------------------------------------
1 | import React from 'react';
2 | import ReactDOM from 'react-dom';
3 | import App from './App';
4 | 
5 | it('renders without crashing', () => {
6 |   const div = document.createElement('div');
7 |   ReactDOM.render(<App />, div);
8 | });
9 | 


--------------------------------------------------------------------------------
/src/index.js:
--------------------------------------------------------------------------------
1 | import React from 'react';
2 | import ReactDOM from 'react-dom';
3 | import './index.css';
4 | import App from './App';
5 | import registerServiceWorker from './registerServiceWorker';
6 | 
7 | ReactDOM.render(<App />, document.getElementById('root'));
8 | registerServiceWorker();
9 | 


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/public/manifest.json:
--------------------------------------------------------------------------------
 1 | {
 2 |   "short_name": "React App",
 3 |   "name": "Create React App Sample",
 4 |   "icons": [
 5 |     {
 6 |       "src": "favicon.ico",
 7 |       "sizes": "192x192",
 8 |       "type": "image/png"
 9 |     }
10 |   ],
11 |   "start_url": "./index.html",
12 |   "display": "standalone",
13 |   "theme_color": "#000000",
14 |   "background_color": "#ffffff"
15 | }
16 | 


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/package.json:
--------------------------------------------------------------------------------
 1 | {
 2 |   "name": "reactnotes",
 3 |   "version": "0.1.0",
 4 |   "private": true,
 5 |   "dependencies": {
 6 |     "firebase": "^4.1.3",
 7 |     "react": "^15.6.1",
 8 |     "react-dom": "^15.6.1",
 9 |     "react-scripts": "1.0.10"
10 |   },
11 |   "scripts": {
12 |     "start": "react-scripts start",
13 |     "build": "react-scripts build",
14 |     "test": "react-scripts test --env=jsdom",
15 |     "eject": "react-scripts eject"
16 |   }
17 | }
18 | 


--------------------------------------------------------------------------------
/.gitignore:
--------------------------------------------------------------------------------
 1 | # See https://help.github.com/ignore-files/ for more about ignoring files.
 2 | 
 3 | # dependencies
 4 | /node_modules
 5 | 
 6 | # testing
 7 | /coverage
 8 | 
 9 | # production
10 | /build
11 | 
12 | # misc
13 | .DS_Store
14 | .env.local
15 | .env.development.local
16 | .env.test.local
17 | .env.production.local
18 | 
19 | npm-debug.log*
20 | yarn-debug.log*
21 | yarn-error.log*
22 | 
23 | /src/Static/img*.jpeg
24 | *.png
25 | 
26 | /src/Config/config.js
27 | 


--------------------------------------------------------------------------------
/src/Note/Note.css:
--------------------------------------------------------------------------------
 1 | .note {
 2 |   padding:10px 10px 38px 34px;
 3 |   height: auto; 
 4 |   margin: auto;
 5 |   margin-bottom: 8px;
 6 |   width: 60%;
 7 |   font-family: 'Lato', sans-serif;
 8 |   font-size: 1.4em;
 9 |   color: #222;
10 |   background-color: #eed; 
11 |   border-radius: 3px;
12 |   box-shadow: 43x 3px 2px #333;
13 |   opacity: 1;
14 | }
15 | 
16 | @keyframes fadeIn { from { opacity:0; } to { opacity:0.8; } }
17 | @keyframes fadeOut { from { opactiy:0.8; } to { opacity:0; } }
18 | 
19 | .fade-in {
20 |     opacity:0;
21 |     animation:fadeIn ease-in 1;
22 |     animation-fill-mode:forwards;
23 |     animation-duration: 0.1s;
24 | }
25 | 
26 | .noteContent{
27 |   float:left;
28 |   padding-right: 70px;
29 |   padding-bottom: 10px;
30 |   display: block;
31 | }
32 | 
33 | .closebtn {
34 |     color: #AA9;
35 |     font-weight: bold;
36 |     float: right;
37 |     cursor: pointer;
38 |     font-size: 1.3em;
39 | }
40 | 
41 | .closebtn:hover {
42 |     color: #AC2500;
43 | }


--------------------------------------------------------------------------------
/src/Note/Note.jsx:
--------------------------------------------------------------------------------
 1 | import React, { Component } from 'react';
 2 | import './Note.css';
 3 | import PropTypes from 'prop-types';
 4 | 
 5 | class Note extends Component{
 6 | 
 7 |     constructor(props){
 8 |         super(props);
 9 |         this.noteContent = props.noteContent; 
10 |         this.noteId = props.noteId; 
11 |         this.handleRemoveNote = this.handleRemoveNote.bind(this);
12 |     }
13 | 
14 |     handleRemoveNote(id){
15 |         this.props.removeNote(id);
16 |     }
17 | 
18 |     render(){
19 |         return(
20 |             <div className="note fade-in">
21 |                 <span className="closebtn" 
22 |                       onClick={() => this.handleRemoveNote(this.noteId)}>
23 |                       &times;
24 |                 </span>
25 |                 <p className="noteContent">{ this.noteContent }</p>
26 |             </div>
27 |         )
28 |     }
29 | }
30 | 
31 | Note.propTypes = {
32 |     noteContent: PropTypes.string
33 | }
34 | 
35 | export default Note;
36 | 


--------------------------------------------------------------------------------
/src/NoteForm/NoteForm.css:
--------------------------------------------------------------------------------
 1 | .formWrapper{
 2 |     margin: auto;
 3 | }
 4 | 
 5 | .noteButton{
 6 |     border: none;
 7 |     margin: 0px;
 8 |     border-top-right-radius: 4px;
 9 |     border-bottom-right-radius: 4px;
10 |     padding: 8px 24px;
11 |     font-size: 1.3em;
12 |     font-family: 'Droid Sans', sans-serif;
13 |     background-color: #019875;
14 |     color: #fff;
15 |     transition: 0.2s ease-out;
16 | }
17 | 
18 | .noteButton:hover{
19 |     background-color: #02BA85;
20 |     color: #fff;
21 |     transition: 0.2s ease-out;
22 | }
23 | 
24 | .noteInput{
25 |     width: 800px;
26 |     min-width: 800px;
27 |     font-size: 1.3em;
28 |     padding-left: 20px;
29 |     border-top-left-radius: 4px;
30 |     border-bottom-left-radius: 4px;
31 |     font-family: 'Droid Sans', sans-serif;
32 |     background-color: rgba(34,49,63,0.8);
33 |     color: #fff;
34 |     transition: 0.2s ease-out;
35 | }
36 | 
37 | .noteInput:focus{
38 |     background-color: #E4F1FE;
39 |     color: #111;
40 |     transition: 0.2s ease-in;
41 | }


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/README.md:
--------------------------------------------------------------------------------
 1 | # react-firebase-notes-app
 2 | ## Summary
 3 | A simple CRUD application to explore React and Firebase interaction. Implements a simple flexbox layout, and provides the ability for a user to add and remove notes from a Firebase database. I created a video tutorial for building the initial version of this app here: [Link to YouTube video](https://youtu.be/-RtJroTMDf4).
 4 | 
 5 | ## Setup
 6 | You'll need to get your connection strings from Firebase. Place a file called `config.js` in `src/Config/` that contains your Firebase config as a simple javascript object, exported as `DB_CONFIG`. For example,
 7 | 
 8 | ```
 9 | export const DB_CONFIG ={
10 |   apiKey: your_api_key,
11 |   authDomain: your_auth_domain,
12 |   // etc..
13 | }
14 | ```
15 | 
16 | ## Starting the app
17 | `npm start`
18 | 
19 | ## Sample Screenshot
20 | 
21 | ![example screenshot](https://github.com/wesdoyle/react-firebase-notes-app/blob/master/src/app.JPG)
22 | 
23 | 
24 | 
25 | This project was bootstrapped with [Create React App](https://github.com/facebookincubator/create-react-app).
26 | 


--------------------------------------------------------------------------------
/LICENSE:
--------------------------------------------------------------------------------
 1 | MIT License
 2 | 
 3 | Copyright (c) 2017 Wes Doyle
 4 | 
 5 | Permission is hereby granted, free of charge, to any person obtaining a copy
 6 | of this software and associated documentation files (the "Software"), to deal
 7 | in the Software without restriction, including without limitation the rights
 8 | to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 9 | copies of the Software, and to permit persons to whom the Software is
10 | furnished to do so, subject to the following conditions:
11 | 
12 | The above copyright notice and this permission notice shall be included in all
13 | copies or substantial portions of the Software.
14 | 
15 | THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16 | IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17 | FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
18 | AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19 | LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
20 | OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
21 | SOFTWARE.
22 | 


--------------------------------------------------------------------------------
/src/App.css:
--------------------------------------------------------------------------------
 1 | html{
 2 |   height: 100%;
 3 | }
 4 | 
 5 | body {
 6 |   width: 100%;
 7 |   min-height:100%;
 8 |   background: 
 9 |     linear-gradient(-45deg, rgba(0,0,0,0.3), rgba(0, 40, 105, 0.8)),
10 |     url('./Static/img/2.jpeg');
11 |   background-attachment: fixed;
12 |   background-size: cover; 
13 | }
14 | 
15 | * {
16 |   height: 100%;
17 |   box-sizing: border-box;
18 |   margin: 0;
19 |   padding: 0;
20 |   border: 0;
21 | }
22 | 
23 | .notesWrapper {
24 |   display: flex;
25 |   flex: 1 1 auto;
26 |   flex-direction: column;
27 |   height: 100%;
28 | }
29 | 
30 | .notesHeader {
31 |   display: flex;
32 |   flex: 1 1 5%;
33 |   min-height: 2.5em;
34 |   max-height: 2em;
35 |   font-size: 3.2em;
36 |   color: #F4B350;
37 |   font-family: 'Permanent Marker', cursive;
38 |   text-align: center;
39 |   align-content: center;
40 |   padding:20px 0px 20px 0px;
41 |   margin-bottom: 6px;
42 |   background-color: rgba(0,0,0,0.5);
43 |   text-shadow: 3px 3px 10px #000;
44 |   display: block;
45 | }
46 | 
47 | .notesBody {
48 |   padding-top: 24px;
49 |   display: flex;
50 |   flex: 1 1 85%;
51 |   flex-wrap: wrap;
52 |   align-items: flex-start;
53 |   align-content: flex-start;
54 |   overflow: auto;
55 | }
56 | 
57 | .notesFooter {
58 |   display: flex;
59 |   flex: 1 1 5%;
60 |   background-color: rgba(0,0,0,0.5);
61 | }


--------------------------------------------------------------------------------
/src/NoteForm/NoteForm.jsx:
--------------------------------------------------------------------------------
 1 | import React, { Component } from 'react';
 2 | import './NoteForm.css';
 3 | 
 4 | class NoteForm extends Component{
 5 |     constructor(props){
 6 |         super(props);
 7 |         this.state = {
 8 |             newNoteContent: '',
 9 |         };
10 | 
11 |         this.handleUserInput = this.handleUserInput.bind(this);
12 |         this.writeNote = this.writeNote.bind(this);
13 |     }
14 | 
15 |     // When the user input changes, set the newNoteContent
16 |     // to the value of what's in the input box.
17 |     handleUserInput(e){
18 |         this.setState({
19 |             newNoteContent: e.target.value, // the value of the text input
20 |         })
21 |     }
22 | 
23 |     writeNote(){
24 |         // call a method that sets the noteContent for a note to
25 |         // the value of the input
26 |         this.props.addNote(this.state.newNoteContent);
27 | 
28 |         // Set newNoteContent back to an empty string.
29 |         this.setState({
30 |             newNoteContent: '',
31 |         })
32 |     }
33 | 
34 |     render(){
35 |         return(
36 |             <div className="formWrapper">
37 |                 <input className="noteInput"
38 |                 placeholder="Write a new note..."
39 |                 value={this.state.newNoteContent} 
40 |                 onChange={this.handleUserInput} />
41 |                 <button className="noteButton"
42 |                 onClick={this.writeNote}>Add Note</button>
43 |             </div>
44 |         )
45 |     }
46 | }
47 | 
48 | export default NoteForm;


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/public/index.html:
--------------------------------------------------------------------------------
 1 | <!doctype html>
 2 | <html lang="en">
 3 |   <head>
 4 |     <meta charset="utf-8">
 5 |     <meta name="viewport" content="width=device-width, initial-scale=1, shrink-to-fit=no">
 6 |     <meta name="theme-color" content="#000000">
 7 |     <!--
 8 |       manifest.json provides metadata used when your web app is added to the
 9 |       homescreen on Android. See https://developers.google.com/web/fundamentals/engage-and-retain/web-app-manifest/
10 |     -->
11 |     <link rel="manifest" href="%PUBLIC_URL%/manifest.json">
12 |     <link rel="shortcut icon" href="%PUBLIC_URL%/favicon.ico">
13 |     <!--
14 |       Notice the use of %PUBLIC_URL% in the tags above.
15 |       It will be replaced with the URL of the `public` folder during the build.
16 |       Only files inside the `public` folder can be referenced from the HTML.
17 | 
18 |       Unlike "/favicon.ico" or "favicon.ico", "%PUBLIC_URL%/favicon.ico" will
19 |       work correctly both with client-side routing and a non-root public URL.
20 |       Learn how to configure a non-root public URL by running `npm run build`.
21 |     -->
22 |     <title>React App</title>
23 |   </head>
24 |   <body>
25 |     <noscript>
26 |       You need to enable JavaScript to run this app.
27 |     </noscript>
28 |     <div id="root"></div>
29 |     <!--
30 |       This HTML file is a template.
31 |       If you open it directly in the browser, you will see an empty page.
32 | 
33 |       You can add webfonts, meta tags, or analytics to this file.
34 |       The build step will place the bundled scripts into the <body> tag.
35 | 
36 |       To begin the development, run `npm start` or `yarn start`.
37 |       To create a production bundle, use `npm run build` or `yarn build`.
38 |     -->
39 |   </body>
40 | </html>
41 | 


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/src/App.js:
--------------------------------------------------------------------------------
 1 | import React, { Component } from 'react';
 2 | import Note from './Note/Note';
 3 | import NoteForm from './NoteForm/NoteForm';
 4 | import { DB_CONFIG } from './Config/config';
 5 | import firebase from 'firebase/app';
 6 | import 'firebase/database';
 7 | import './App.css';
 8 | 
 9 | class App extends Component {
10 | 
11 |   constructor(props){
12 |     super(props);
13 |     this.addNote = this.addNote.bind(this);
14 |     this.removeNote = this.removeNote.bind(this);
15 | 
16 |     this.app = firebase.initializeApp(DB_CONFIG);
17 |     this.database = this.app.database().ref().child('notes');
18 | 
19 |     // We're going to setup the React state of our component
20 |     this.state = {
21 |       notes: [],
22 |     }
23 |   }
24 | 
25 |   componentWillMount(){
26 |     const previousNotes = this.state.notes;
27 | 
28 |     // DataSnapshot
29 |     this.database.on('child_added', snap => {
30 |       previousNotes.push({
31 |         id: snap.key,
32 |         noteContent: snap.val().noteContent,
33 |       })
34 | 
35 |       this.setState({
36 |         notes: previousNotes
37 |       })
38 |     })
39 | 
40 |     this.database.on('child_removed', snap => {
41 |       for(var i=0; i < previousNotes.length; i++){
42 |         if(previousNotes[i].id === snap.key){
43 |           previousNotes.splice(i, 1);
44 |         }
45 |       }
46 | 
47 |       this.setState({
48 |         notes: previousNotes
49 |       })
50 |     })
51 |   }
52 | 
53 |   addNote(note){
54 |     this.database.push().set({ noteContent: note});
55 |   }
56 | 
57 |   removeNote(noteId){
58 |     console.log("from the parent: " + noteId);
59 |     this.database.child(noteId).remove();
60 |   }
61 | 
62 |   render() {
63 |     return (
64 |       <div className="notesWrapper">
65 |         <div className="notesHeader">
66 |           <div className="heading">React & Firebase To-Do List</div>
67 |         </div>
68 |         <div className="notesBody">
69 |           {
70 |             this.state.notes.map((note) => {
71 |               return (
72 |                 <Note noteContent={note.noteContent} 
73 |                 noteId={note.id} 
74 |                 key={note.id} 
75 |                 removeNote ={this.removeNote}/>
76 |               )
77 |             })
78 |           }
79 |         </div>
80 |         <div className="notesFooter">
81 |           <NoteForm addNote={this.addNote} />
82 |         </div>
83 |       </div>
84 |     );
85 |   }
86 | }
87 | 
88 | export default App;
89 | 


--------------------------------------------------------------------------------
/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/registerServiceWorker.js:
--------------------------------------------------------------------------------
  1 | // In production, we register a service worker to serve assets from local cache.
  2 | 
  3 | // This lets the app load faster on subsequent visits in production, and gives
  4 | // it offline capabilities. However, it also means that developers (and users)
  5 | // will only see deployed updates on the "N+1" visit to a page, since previously
  6 | // cached resources are updated in the background.
  7 | 
  8 | // To learn more about the benefits of this model, read https://goo.gl/KwvDNy.
  9 | // This link also includes instructions on opting out of this behavior.
 10 | 
 11 | const isLocalhost = Boolean(
 12 |   window.location.hostname === 'localhost' ||
 13 |     // [::1] is the IPv6 localhost address.
 14 |     window.location.hostname === '[::1]' ||
 15 |     // 127.0.0.1/8 is considered localhost for IPv4.
 16 |     window.location.hostname.match(
 17 |       /^127(?:\.(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)){3}$/
 18 |     )
 19 | );
 20 | 
 21 | export default function register() {
 22 |   if (process.env.NODE_ENV === 'production' && 'serviceWorker' in navigator) {
 23 |     // The URL constructor is available in all browsers that support SW.
 24 |     const publicUrl = new URL(process.env.PUBLIC_URL, window.location);
 25 |     if (publicUrl.origin !== window.location.origin) {
 26 |       // Our service worker won't work if PUBLIC_URL is on a different origin
 27 |       // from what our page is served on. This might happen if a CDN is used to
 28 |       // serve assets; see https://github.com/facebookincubator/create-react-app/issues/2374
 29 |       return;
 30 |     }
 31 | 
 32 |     window.addEventListener('load', () => {
 33 |       const swUrl = `${process.env.PUBLIC_URL}/service-worker.js`;
 34 | 
 35 |       if (!isLocalhost) {
 36 |         // Is not local host. Just register service worker
 37 |         registerValidSW(swUrl);
 38 |       } else {
 39 |         // This is running on localhost. Lets check if a service worker still exists or not.
 40 |         checkValidServiceWorker(swUrl);
 41 |       }
 42 |     });
 43 |   }
 44 | }
 45 | 
 46 | function registerValidSW(swUrl) {
 47 |   navigator.serviceWorker
 48 |     .register(swUrl)
 49 |     .then(registration => {
 50 |       registration.onupdatefound = () => {
 51 |         const installingWorker = registration.installing;
 52 |         installingWorker.onstatechange = () => {
 53 |           if (installingWorker.state === 'installed') {
 54 |             if (navigator.serviceWorker.controller) {
 55 |               // At this point, the old content will have been purged and
 56 |               // the fresh content will have been added to the cache.
 57 |               // It's the perfect time to display a "New content is
 58 |               // available; please refresh." message in your web app.
 59 |               console.log('New content is available; please refresh.');
 60 |             } else {
 61 |               // At this point, everything has been precached.
 62 |               // It's the perfect time to display a
 63 |               // "Content is cached for offline use." message.
 64 |               console.log('Content is cached for offline use.');
 65 |             }
 66 |           }
 67 |         };
 68 |       };
 69 |     })
 70 |     .catch(error => {
 71 |       console.error('Error during service worker registration:', error);
 72 |     });
 73 | }
 74 | 
 75 | function checkValidServiceWorker(swUrl) {
 76 |   // Check if the service worker can be found. If it can't reload the page.
 77 |   fetch(swUrl)
 78 |     .then(response => {
 79 |       // Ensure service worker exists, and that we really are getting a JS file.
 80 |       if (
 81 |         response.status === 404 ||
 82 |         response.headers.get('content-type').indexOf('javascript') === -1
 83 |       ) {
 84 |         // No service worker found. Probably a different app. Reload the page.
 85 |         navigator.serviceWorker.ready.then(registration => {
 86 |           registration.unregister().then(() => {
 87 |             window.location.reload();
 88 |           });
 89 |         });
 90 |       } else {
 91 |         // Service worker found. Proceed as normal.
 92 |         registerValidSW(swUrl);
 93 |       }
 94 |     })
 95 |     .catch(() => {
 96 |       console.log(
 97 |         'No internet connection found. App is running in offline mode.'
 98 |       );
 99 |     });
100 | }
101 | 
102 | export function unregister() {
103 |   if ('serviceWorker' in navigator) {
104 |     navigator.serviceWorker.ready.then(registration => {
105 |       registration.unregister();
106 |     });
107 |   }
108 | }
109 | 


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