├── .travis.yml
├── index.js
├── .gitignore
├── babel.config.js
├── hardware-concurrency
    ├── index.js
    └── hardware-concurrency.test.js
├── package.json
├── save-data
    ├── index.js
    └── save-data.test.js
├── CONTRIBUTING.md
├── media-capabilities
    ├── index.js
    └── media-capabilities.test.js
├── memory
    ├── index.js
    └── memory.test.js
├── network
    ├── index.js
    └── network.test.js
├── LICENSE
└── README.md


/.travis.yml:
--------------------------------------------------------------------------------
 1 | language: node_js
 2 | node_js:
 3 |   - node
 4 | branches:
 5 |   only:
 6 |     - master
 7 | cache:
 8 |   npm: true
 9 |   directories:
10 |     - node_modules
11 | notifications:
12 |   email: false
13 | install:
14 |   - npm ci
15 | script: npm run test
16 | 


--------------------------------------------------------------------------------
/index.js:
--------------------------------------------------------------------------------
1 | export { useNetworkStatus } from './network';
2 | export { useSaveData } from './save-data';
3 | export { useMemoryStatus } from './memory';
4 | export { useHardwareConcurrency } from './hardware-concurrency';
5 | export { useMediaCapabilitiesDecodingInfo } from './media-capabilities';
6 | 


--------------------------------------------------------------------------------
/.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 | /dist
14 | 
15 | # misc
16 | .DS_Store
17 | .env.local
18 | .env.development.local
19 | .env.test.local
20 | .env.production.local
21 | 
22 | npm-debug.log*
23 | yarn-debug.log*
24 | yarn-error.log*
25 | 


--------------------------------------------------------------------------------
/babel.config.js:
--------------------------------------------------------------------------------
 1 | /*
 2 |  * Copyright 2019 Google LLC
 3 |  *
 4 |  * Licensed under the Apache License, Version 2.0 (the 'License');
 5 |  * you may not use this file except in compliance with the License.
 6 |  * You may obtain a copy of the License at
 7 |  *
 8 |  *     https://www.apache.org/licenses/LICENSE-2.0
 9 |  *
10 |  * Unless required by applicable law or agreed to in writing, software
11 |  * distributed under the License is distributed on an 'AS IS' BASIS,
12 |  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 |  * See the License for the specific language governing permissions and
14 |  * limitations under the License.
15 |  */
16 | 
17 | module.exports = {
18 |   presets: [
19 |     "@babel/preset-env"
20 |   ]
21 | };
22 | 


--------------------------------------------------------------------------------
/hardware-concurrency/index.js:
--------------------------------------------------------------------------------
 1 | /*
 2 |  * Copyright 2019 Google LLC
 3 |  *
 4 |  * Licensed under the Apache License, Version 2.0 (the "License");
 5 |  * you may not use this file except in compliance with the License.
 6 |  * You may obtain a copy of the License at
 7 |  *
 8 |  *     https://www.apache.org/licenses/LICENSE-2.0
 9 |  *
10 |  * Unless required by applicable law or agreed to in writing, software
11 |  * distributed under the License is distributed on an "AS IS" BASIS,
12 |  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 |  * See the License for the specific language governing permissions and
14 |  * limitations under the License.
15 |  */
16 | 
17 | let initialHardwareConcurrency;
18 | if (typeof navigator !== 'undefined' && 'hardwareConcurrency' in navigator) {
19 |   initialHardwareConcurrency = {
20 |     unsupported: false,
21 |     numberOfLogicalProcessors: navigator.hardwareConcurrency
22 |   };
23 | } else {
24 |   initialHardwareConcurrency = { unsupported: true };
25 | }
26 | const useHardwareConcurrency = () => {
27 |   return { ...initialHardwareConcurrency };
28 | };
29 | 
30 | export { useHardwareConcurrency };
31 | 


--------------------------------------------------------------------------------
/package.json:
--------------------------------------------------------------------------------
 1 | {
 2 |   "name": "react-adaptive-hooks",
 3 |   "version": "0.1.0",
 4 |   "description": "Give users a great experience best suited to their device and network constraints",
 5 |   "repository": "https://github.com/GoogleChromeLabs/react-adaptive-hooks",
 6 |   "author": "Google Chrome",
 7 |   "license": "Apache-2.0",
 8 |   "private": false,
 9 |   "main": "dist/index.js",
10 |   "module": "dist/index.module.js",
11 |   "unpkg": "dist/index.umd.js",
12 |   "source": "index.js",
13 |   "scripts": {
14 |     "build": "microbundle",
15 |     "dev": "microbundle watch",
16 |     "prepare": "npm run build",
17 |     "test": "jest",
18 |     "test:coverage": "jest --coverage"
19 |   },
20 |   "peerDependencies": {
21 |     "react": "^16.8.0 || ^17.0.0"
22 |   },
23 |   "devDependencies": {
24 |     "@babel/preset-env": "^7.5.5",
25 |     "@testing-library/react-hooks": "^1.1.0",
26 |     "babel-polyfill": "^6.26.0",
27 |     "jest": "^24.8.0",
28 |     "microbundle": "0.11.0",
29 |     "react": "17.0.1",
30 |     "react-test-renderer": "17.0.1"
31 |   },
32 |   "keywords": [
33 |     "react-hooks",
34 |     "hooks",
35 |     "react",
36 |     "performance"
37 |   ]
38 | }
39 | 


--------------------------------------------------------------------------------
/save-data/index.js:
--------------------------------------------------------------------------------
 1 | /*
 2 |  * Copyright 2019 Google LLC
 3 |  *
 4 |  * Licensed under the Apache License, Version 2.0 (the "License");
 5 |  * you may not use this file except in compliance with the License.
 6 |  * You may obtain a copy of the License at
 7 |  *
 8 |  *     https://www.apache.org/licenses/LICENSE-2.0
 9 |  *
10 |  * Unless required by applicable law or agreed to in writing, software
11 |  * distributed under the License is distributed on an "AS IS" BASIS,
12 |  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 |  * See the License for the specific language governing permissions and
14 |  * limitations under the License.
15 |  */
16 | 
17 | let unsupported;
18 | 
19 | const useSaveData = (initialSaveData = null) => {
20 |   if (typeof navigator !== 'undefined' && 'connection' in navigator && 'saveData' in navigator.connection) {
21 |     unsupported = false;
22 |   } else {
23 |     unsupported = true;
24 |   }
25 | 
26 |   return {
27 |     unsupported,
28 |     saveData: unsupported
29 |       ? initialSaveData
30 |       : navigator.connection.saveData === true
31 |   };
32 | };
33 | 
34 | export { useSaveData };
35 | 


--------------------------------------------------------------------------------
/CONTRIBUTING.md:
--------------------------------------------------------------------------------
 1 | # How to Contribute
 2 | 
 3 | We'd love to accept your patches and contributions to this project. There are
 4 | just a few small guidelines you need to follow.
 5 | 
 6 | ## Contributor License Agreement
 7 | 
 8 | Contributions to this project must be accompanied by a Contributor License
 9 | Agreement. You (or your employer) retain the copyright to your contribution;
10 | this simply gives us permission to use and redistribute your contributions as
11 | part of the project. Head over to <https://cla.developers.google.com/> to see
12 | your current agreements on file or to sign a new one.
13 | 
14 | You generally only need to submit a CLA once, so if you've already submitted one
15 | (even if it was for a different project), you probably don't need to do it
16 | again.
17 | 
18 | ## Code reviews
19 | 
20 | All submissions, including submissions by project members, require review. We
21 | use GitHub pull requests for this purpose. Consult
22 | [GitHub Help](https://help.github.com/articles/about-pull-requests/) for more
23 | information on using pull requests.
24 | 
25 | ## Community Guidelines
26 | 
27 | This project follows [Google's Open Source Community
28 | Guidelines](https://opensource.google.com/conduct/).
29 | 


--------------------------------------------------------------------------------
/media-capabilities/index.js:
--------------------------------------------------------------------------------
 1 | /*
 2 |  * Copyright 2019 Google LLC
 3 |  *
 4 |  * Licensed under the Apache License, Version 2.0 (the "License");
 5 |  * you may not use this file except in compliance with the License.
 6 |  * You may obtain a copy of the License at
 7 |  *
 8 |  *     https://www.apache.org/licenses/LICENSE-2.0
 9 |  *
10 |  * Unless required by applicable law or agreed to in writing, software
11 |  * distributed under the License is distributed on an "AS IS" BASIS,
12 |  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 |  * See the License for the specific language governing permissions and
14 |  * limitations under the License.
15 |  */
16 | 
17 | import { useState, useEffect } from 'react';
18 | 
19 | const useMediaCapabilitiesDecodingInfo = (mediaDecodingConfig, initialMediaCapabilitiesInfo = {}) => {
20 |   const supported = typeof navigator !== 'undefined' && 'mediaCapabilities' in navigator;
21 |   const [mediaCapabilitiesInfo, setMediaCapabilitiesInfo] = useState(initialMediaCapabilitiesInfo);
22 | 
23 |   useEffect(() => {
24 |     supported &&
25 |     navigator
26 |       .mediaCapabilities
27 |       .decodingInfo(mediaDecodingConfig)
28 |       .then(setMediaCapabilitiesInfo)
29 |       .catch(error => console.error(error));
30 |   }, [mediaDecodingConfig]);
31 | 
32 |   return { supported, mediaCapabilitiesInfo };
33 | };
34 | 
35 | export { useMediaCapabilitiesDecodingInfo };
36 | 


--------------------------------------------------------------------------------
/memory/index.js:
--------------------------------------------------------------------------------
 1 | /*
 2 |  * Copyright 2019 Google LLC
 3 |  *
 4 |  * Licensed under the Apache License, Version 2.0 (the 'License');
 5 |  * you may not use this file except in compliance with the License.
 6 |  * You may obtain a copy of the License at
 7 |  *
 8 |  *     https://www.apache.org/licenses/LICENSE-2.0
 9 |  *
10 |  * Unless required by applicable law or agreed to in writing, software
11 |  * distributed under the License is distributed on an 'AS IS' BASIS,
12 |  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 |  * See the License for the specific language governing permissions and
14 |  * limitations under the License.
15 |  */
16 | 
17 | let unsupported;
18 | if (typeof navigator !== 'undefined' && 'deviceMemory' in navigator) {
19 |   unsupported = false;
20 | } else {
21 |   unsupported = true;
22 | }
23 | let memoryStatus;
24 | if (!unsupported) {
25 |   const performanceMemory = 'memory' in performance ? performance.memory : null;
26 |   memoryStatus = {
27 |     unsupported,
28 |     deviceMemory: navigator.deviceMemory,
29 |     totalJSHeapSize: performanceMemory
30 |       ? performanceMemory.totalJSHeapSize
31 |       : null,
32 |     usedJSHeapSize: performanceMemory ? performanceMemory.usedJSHeapSize : null,
33 |     jsHeapSizeLimit: performanceMemory
34 |       ? performanceMemory.jsHeapSizeLimit
35 |       : null
36 |   };
37 | } else {
38 |   memoryStatus = { unsupported };
39 | }
40 | 
41 | const useMemoryStatus = initialMemoryStatus => {
42 |   return unsupported && initialMemoryStatus
43 |     ? { ...memoryStatus, ...initialMemoryStatus }
44 |     : { ...memoryStatus };
45 | };
46 | 
47 | export { useMemoryStatus };
48 | 


--------------------------------------------------------------------------------
/network/index.js:
--------------------------------------------------------------------------------
 1 | /*
 2 |  * Copyright 2019 Google LLC
 3 |  *
 4 |  * Licensed under the Apache License, Version 2.0 (the 'License');
 5 |  * you may not use this file except in compliance with the License.
 6 |  * You may obtain a copy of the License at
 7 |  *
 8 |  *     https://www.apache.org/licenses/LICENSE-2.0
 9 |  *
10 |  * Unless required by applicable law or agreed to in writing, software
11 |  * distributed under the License is distributed on an 'AS IS' BASIS,
12 |  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 |  * See the License for the specific language governing permissions and
14 |  * limitations under the License.
15 |  */
16 | 
17 | import { useState, useEffect } from 'react';
18 | 
19 | let unsupported;
20 | 
21 | const useNetworkStatus = initialEffectiveConnectionType => {
22 |   if (typeof navigator !== 'undefined' && 'connection' in navigator && 'effectiveType' in navigator.connection) {
23 |     unsupported = false;
24 |   } else {
25 |     unsupported = true;
26 |   }
27 | 
28 |   const initialNetworkStatus = {
29 |     unsupported,
30 |     effectiveConnectionType: unsupported
31 |       ? initialEffectiveConnectionType
32 |       : navigator.connection.effectiveType
33 |   };
34 | 
35 |   const [networkStatus, setNetworkStatus] = useState(initialNetworkStatus);
36 | 
37 |   useEffect(() => {
38 |     if (!unsupported) {
39 |       const navigatorConnection = navigator.connection;
40 |       const updateECTStatus = () => {
41 |         setNetworkStatus({
42 |           effectiveConnectionType: navigatorConnection.effectiveType
43 |         });
44 |       };
45 |       navigatorConnection.addEventListener('change', updateECTStatus);
46 |       return () => {
47 |         navigatorConnection.removeEventListener('change', updateECTStatus);
48 |       };
49 |     }
50 |   }, []);
51 | 
52 |   return { ...networkStatus, setNetworkStatus };
53 | };
54 | 
55 | export { useNetworkStatus };
56 | 


--------------------------------------------------------------------------------
/hardware-concurrency/hardware-concurrency.test.js:
--------------------------------------------------------------------------------
 1 | /*
 2 |  * Copyright 2019 Google LLC
 3 |  *
 4 |  * Licensed under the Apache License, Version 2.0 (the 'License');
 5 |  * you may not use this file except in compliance with the License.
 6 |  * You may obtain a copy of the License at
 7 |  *
 8 |  *     https://www.apache.org/licenses/LICENSE-2.0
 9 |  *
10 |  * Unless required by applicable law or agreed to in writing, software
11 |  * distributed under the License is distributed on an 'AS IS' BASIS,
12 |  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 |  * See the License for the specific language governing permissions and
14 |  * limitations under the License.
15 |  */
16 | 
17 | import { renderHook } from '@testing-library/react-hooks';
18 | 
19 | afterEach(function() {
20 |   // Reload hook for every test
21 |   jest.resetModules();
22 | });
23 | 
24 | describe('useHardwareConcurrency', () => {
25 |   const navigator = window.navigator;
26 | 
27 |   afterEach(() => {
28 |     if (!window.navigator) window.navigator = navigator;
29 |   });
30 | 
31 |   test(`should return "true" for unsupported case`, () => {
32 |     Object.defineProperty(window, 'navigator', {
33 |       value: undefined,
34 |       configurable: true,
35 |       writable: true
36 |     });
37 | 
38 |     const { useHardwareConcurrency } = require('./');
39 |     const { result } = renderHook(() => useHardwareConcurrency());
40 | 
41 |     expect(result.current.unsupported).toBe(true);
42 |   });
43 | 
44 |   test(`should return window.navigator.hardwareConcurrency`, () => {
45 |     const { useHardwareConcurrency } = require('./');
46 |     const { result } = renderHook(() => useHardwareConcurrency());
47 | 
48 |     expect(result.current.numberOfLogicalProcessors).toBe(
49 |       window.navigator.hardwareConcurrency
50 |     );
51 |     expect(result.current.unsupported).toBe(false);
52 |   });
53 | 
54 |   test('should return 4 for device of hardwareConcurrency = 4', () => {
55 |     Object.defineProperty(window.navigator, 'hardwareConcurrency', {
56 |       value: 4,
57 |       configurable: true,
58 |       writable: true
59 |     });
60 |     const { useHardwareConcurrency } = require('./');
61 |     const { result } = renderHook(() => useHardwareConcurrency());
62 | 
63 |     expect(result.current.numberOfLogicalProcessors).toEqual(4);
64 |     expect(result.current.unsupported).toBe(false);
65 |   });
66 | 
67 |   test('should return 2 for device of hardwareConcurrency = 2', () => {
68 |     Object.defineProperty(window.navigator, 'hardwareConcurrency', {
69 |       value: 2,
70 |       configurable: true,
71 |       writable: true
72 |     });
73 |     const { useHardwareConcurrency } = require('./');
74 |     const { result } = renderHook(() => useHardwareConcurrency());
75 | 
76 |     expect(result.current.numberOfLogicalProcessors).toEqual(2);
77 |     expect(result.current.unsupported).toBe(false);
78 |   });
79 | });
80 | 


--------------------------------------------------------------------------------
/save-data/save-data.test.js:
--------------------------------------------------------------------------------
 1 | /*
 2 |  * Copyright 2019 Google LLC
 3 |  *
 4 |  * Licensed under the Apache License, Version 2.0 (the 'License');
 5 |  * you may not use this file except in compliance with the License.
 6 |  * You may obtain a copy of the License at
 7 |  *
 8 |  *     https://www.apache.org/licenses/LICENSE-2.0
 9 |  *
10 |  * Unless required by applicable law or agreed to in writing, software
11 |  * distributed under the License is distributed on an 'AS IS' BASIS,
12 |  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 |  * See the License for the specific language governing permissions and
14 |  * limitations under the License.
15 |  */
16 | 
17 | import { renderHook, act } from '@testing-library/react-hooks';
18 | 
19 | afterEach(function() {
20 |   // Reload hook for every test
21 |   jest.resetModules();
22 | });
23 | 
24 | describe('useSaveData', () => {
25 |   test(`should return "true" for unsupported case`, () => {
26 |     const { useSaveData } = require('./');
27 |     const { result } = renderHook(() => useSaveData());
28 | 
29 |     expect(result.current.unsupported).toBe(true);
30 |     expect(result.current.saveData).toEqual(null);
31 |   });
32 | 
33 |   test('should return initialSaveData for unsupported case', () => {
34 |     const initialSaveData = true;
35 |     const { useSaveData } = require('./');
36 |     const { result } = renderHook(() => useSaveData(initialSaveData));
37 | 
38 |     expect(result.current.unsupported).toBe(true);
39 |     expect(result.current.saveData).toBe(initialSaveData);
40 |   });
41 | 
42 |   test(`should return "true" for enabled save data`, () => {
43 |     global.navigator.connection = {
44 |       saveData: true
45 |     };
46 |     const { useSaveData } = require('./');
47 |     const { result } = renderHook(() => useSaveData());
48 | 
49 |     expect(result.current.unsupported).toBe(false);
50 |     expect(result.current.saveData).toEqual(navigator.connection.saveData);
51 |   });
52 | 
53 |   test(`should return "false" for disabled save data`, () => {
54 |     global.navigator.connection = {
55 |       saveData: false
56 |     };
57 |     const { useSaveData } = require('./');
58 |     const { result } = renderHook(() => useSaveData());
59 | 
60 |     expect(result.current.unsupported).toBe(false);
61 |     expect(result.current.saveData).toEqual(navigator.connection.saveData);
62 |   });
63 | 
64 |   test('should not return initialSaveData for supported case', () => {
65 |     const initialSaveData = false;
66 |     global.navigator.connection = {
67 |       saveData: true
68 |     };
69 |     const { useSaveData } = require('./');
70 |     const { result } = renderHook(() => useSaveData(initialSaveData));
71 | 
72 |     expect(result.current.unsupported).toBe(false);
73 |     expect(result.current.saveData).toEqual(navigator.connection.saveData);
74 |   });
75 | });
76 | 


--------------------------------------------------------------------------------
/memory/memory.test.js:
--------------------------------------------------------------------------------
  1 | /*
  2 |  * Copyright 2019 Google LLC
  3 |  *
  4 |  * Licensed under the Apache License, Version 2.0 (the 'License');
  5 |  * you may not use this file except in compliance with the License.
  6 |  * You may obtain a copy of the License at
  7 |  *
  8 |  *     https://www.apache.org/licenses/LICENSE-2.0
  9 |  *
 10 |  * Unless required by applicable law or agreed to in writing, software
 11 |  * distributed under the License is distributed on an 'AS IS' BASIS,
 12 |  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 13 |  * See the License for the specific language governing permissions and
 14 |  * limitations under the License.
 15 |  */
 16 | 
 17 | import { renderHook } from '@testing-library/react-hooks';
 18 | 
 19 | afterEach(function() {
 20 |   // Reload hook for every test
 21 |   jest.resetModules();
 22 | });
 23 | 
 24 | const getMemoryStatus = currentResult => ({
 25 |   unsupported: false,
 26 |   deviceMemory: currentResult.deviceMemory,
 27 |   totalJSHeapSize: currentResult.totalJSHeapSize,
 28 |   usedJSHeapSize: currentResult.usedJSHeapSize,
 29 |   jsHeapSizeLimit: currentResult.jsHeapSizeLimit
 30 | });
 31 | 
 32 | describe('useMemoryStatus', () => {
 33 |   test(`should return "true" for unsupported case`, () => {
 34 |     const { useMemoryStatus } = require('./');
 35 |     const { result } = renderHook(() => useMemoryStatus());
 36 | 
 37 |     expect(result.current.unsupported).toBe(true);
 38 |   });
 39 | 
 40 |   test('should return initialMemoryStatus for unsupported case', () => {
 41 |     const mockInitialMemoryStatus = {
 42 |       deviceMemory: 4
 43 |     };
 44 |     const { deviceMemory } = mockInitialMemoryStatus;
 45 | 
 46 |     const { useMemoryStatus } = require('./');
 47 |     const { result } = renderHook(() =>
 48 |       useMemoryStatus(mockInitialMemoryStatus)
 49 |     );
 50 | 
 51 |     expect(result.current.unsupported).toBe(true);
 52 |     expect(result.current.deviceMemory).toEqual(deviceMemory);
 53 |   });
 54 | 
 55 |   test('should return mockMemory status', () => {
 56 |     const mockMemoryStatus = {
 57 |       deviceMemory: 4,
 58 |       totalJSHeapSize: 60,
 59 |       usedJSHeapSize: 40,
 60 |       jsHeapSizeLimit: 50
 61 |     };
 62 | 
 63 |     global.navigator.deviceMemory = mockMemoryStatus.deviceMemory;
 64 | 
 65 |     global.window.performance.memory = {
 66 |       totalJSHeapSize: mockMemoryStatus.totalJSHeapSize,
 67 |       usedJSHeapSize: mockMemoryStatus.usedJSHeapSize,
 68 |       jsHeapSizeLimit: mockMemoryStatus.jsHeapSizeLimit
 69 |     };
 70 | 
 71 |     const { useMemoryStatus } = require('./');
 72 |     const { result } = renderHook(() => useMemoryStatus());
 73 | 
 74 |     expect(getMemoryStatus(result.current)).toEqual({
 75 |       ...mockMemoryStatus,
 76 |       unsupported: false
 77 |     });
 78 |   });
 79 | 
 80 |   test('should return mockMemory status without performance memory data', () => {
 81 |     const mockMemoryStatus = {
 82 |       deviceMemory: 4
 83 |     };
 84 | 
 85 |     global.navigator.deviceMemory = mockMemoryStatus.deviceMemory;
 86 |     delete global.window.performance.memory;
 87 | 
 88 |     const { useMemoryStatus } = require('./');
 89 |     const { result } = renderHook(() => useMemoryStatus());
 90 | 
 91 |     expect(result.current.deviceMemory).toEqual(mockMemoryStatus.deviceMemory);
 92 |     expect(result.current.unsupported).toEqual(false);
 93 |   });
 94 | 
 95 |   test('should not return initialMemoryStatus for supported case', () => {
 96 |     const mockMemoryStatus = {
 97 |       deviceMemory: 4,
 98 |       totalJSHeapSize: 60,
 99 |       usedJSHeapSize: 40,
100 |       jsHeapSizeLimit: 50
101 |     };
102 |     const mockInitialMemoryStatus = {
103 |       deviceMemory: 4
104 |     };
105 | 
106 |     global.navigator.deviceMemory = mockMemoryStatus.deviceMemory;
107 | 
108 |     global.window.performance.memory = {
109 |       totalJSHeapSize: mockMemoryStatus.totalJSHeapSize,
110 |       usedJSHeapSize: mockMemoryStatus.usedJSHeapSize,
111 |       jsHeapSizeLimit: mockMemoryStatus.jsHeapSizeLimit
112 |     };
113 | 
114 |     const { useMemoryStatus } = require('./');
115 |     const { result } = renderHook(() =>
116 |       useMemoryStatus(mockInitialMemoryStatus)
117 |     );
118 | 
119 |     expect(getMemoryStatus(result.current)).toEqual({
120 |       ...mockMemoryStatus,
121 |       unsupported: false
122 |     });
123 |   });
124 | });
125 | 


--------------------------------------------------------------------------------
/media-capabilities/media-capabilities.test.js:
--------------------------------------------------------------------------------
  1 | /*
  2 |  * Copyright 2019 Google LLC
  3 |  *
  4 |  * Licensed under the Apache License, Version 2.0 (the 'License');
  5 |  * you may not use this file except in compliance with the License.
  6 |  * You may obtain a copy of the License at
  7 |  *
  8 |  *     https://www.apache.org/licenses/LICENSE-2.0
  9 |  *
 10 |  * Unless required by applicable law or agreed to in writing, software
 11 |  * distributed under the License is distributed on an 'AS IS' BASIS,
 12 |  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 13 |  * See the License for the specific language governing permissions and
 14 |  * limitations under the License.
 15 |  */
 16 | 
 17 | import 'babel-polyfill';
 18 | import { renderHook } from '@testing-library/react-hooks';
 19 | 
 20 | const mediaDecodingConfig = {
 21 |   type: 'file',
 22 |   audio: {
 23 |     contentType: 'audio/mp3',
 24 |     channels: 2,
 25 |     bitrate: 132700,
 26 |     samplerate: 5200
 27 |   }
 28 | };
 29 | 
 30 | const mediaCapabilitiesMapper = {
 31 |   'audio/mp3': {
 32 |     powerEfficient: true,
 33 |     smooth: true,
 34 |     supported: true
 35 |   }
 36 | };
 37 | 
 38 | describe('useMediaCapabilitiesDecodingInfo', () => {
 39 |   test('should return supported flag on unsupported platforms', () => {
 40 |     const { useMediaCapabilitiesDecodingInfo } = require('./');
 41 |     const { result } = renderHook(() => useMediaCapabilitiesDecodingInfo(mediaDecodingConfig));
 42 | 
 43 |     expect(result.current.supported).toEqual(false);
 44 |   });
 45 | 
 46 |   test('should return supported flag on unsupported platforms and no config given', () => {
 47 |     const { useMediaCapabilitiesDecodingInfo } = require('./');
 48 |     const { result } = renderHook(() => useMediaCapabilitiesDecodingInfo());
 49 |     
 50 |     expect(result.current.supported).toEqual(false);
 51 |   });
 52 | 
 53 |   test('should return initialMediaCapabilitiesInfo for unsupported', () => {
 54 |     const initialMediaCapabilitiesInfo = {
 55 |       supported: true,
 56 |       smooth: false,
 57 |       powerEfficient: true
 58 |     };
 59 | 
 60 |     const { useMediaCapabilitiesDecodingInfo } = require('./');
 61 |     const { result } = renderHook(() => useMediaCapabilitiesDecodingInfo(mediaDecodingConfig, initialMediaCapabilitiesInfo));
 62 | 
 63 |     expect(result.current.mediaCapabilitiesInfo.supported).toBe(true);
 64 |     expect(result.current.mediaCapabilitiesInfo.smooth).toEqual(false);
 65 |     expect(result.current.mediaCapabilitiesInfo.powerEfficient).toEqual(true);
 66 |   });
 67 | 
 68 |   test('should return supported flag when no config given', async () => {
 69 |     const originalError = console.error;
 70 |     console.error = jest.fn();
 71 | 
 72 |     const mockDecodingInfo = jest.fn().mockImplementation(() => Promise.resolve({
 73 |       supported: true
 74 |     }));
 75 | 
 76 |     global.navigator.mediaCapabilities = {
 77 |       decodingInfo: mockDecodingInfo
 78 |     };
 79 | 
 80 |     const { useMediaCapabilitiesDecodingInfo } = require('./');
 81 | 
 82 |     try {
 83 |       const { result, waitForNextUpdate } = renderHook(() => useMediaCapabilitiesDecodingInfo());
 84 |       await waitForNextUpdate();
 85 | 
 86 |       expect(result.current.supported).toEqual(true);
 87 |     } finally {
 88 |       console.error = originalError;
 89 |     }
 90 |   });
 91 | 
 92 |   test('should return mediaCapabilitiesInfo for given media configuration', async () => {
 93 |     const originalError = console.error;
 94 |     console.error = jest.fn();
 95 | 
 96 |     const mockDecodingInfo = jest.fn().mockImplementation(() => Promise.resolve({
 97 |       ...mediaCapabilitiesMapper[mediaDecodingConfig.audio.contentType]
 98 |     }));
 99 | 
100 |     global.navigator.mediaCapabilities = {
101 |       decodingInfo: mockDecodingInfo
102 |     };
103 | 
104 |     const { useMediaCapabilitiesDecodingInfo } = require('./');
105 | 
106 |     try {
107 |       const { result, waitForNextUpdate } = renderHook(() => useMediaCapabilitiesDecodingInfo(mediaDecodingConfig));
108 |       await waitForNextUpdate();
109 | 
110 |       expect(result.current.mediaCapabilitiesInfo.powerEfficient).toEqual(true);
111 |       expect(result.current.mediaCapabilitiesInfo.smooth).toEqual(true);
112 |       expect(result.current.mediaCapabilitiesInfo.supported).toEqual(true);
113 |     } finally {
114 |       console.error = originalError;
115 |     }
116 |   });
117 | });
118 | 


--------------------------------------------------------------------------------
/network/network.test.js:
--------------------------------------------------------------------------------
  1 | /*
  2 |  * Copyright 2019 Google LLC
  3 |  *
  4 |  * Licensed under the Apache License, Version 2.0 (the 'License');
  5 |  * you may not use this file except in compliance with the License.
  6 |  * You may obtain a copy of the License at
  7 |  *
  8 |  *     https://www.apache.org/licenses/LICENSE-2.0
  9 |  *
 10 |  * Unless required by applicable law or agreed to in writing, software
 11 |  * distributed under the License is distributed on an 'AS IS' BASIS,
 12 |  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 13 |  * See the License for the specific language governing permissions and
 14 |  * limitations under the License.
 15 |  */
 16 | 
 17 | import { renderHook, act } from '@testing-library/react-hooks';
 18 | 
 19 | import { useNetworkStatus } from './';
 20 | 
 21 | describe('useNetworkStatus', () => {
 22 |   const map = {};
 23 | 
 24 |   const ectStatusListeners = {
 25 |     addEventListener: jest.fn().mockImplementation((event, callback) => {
 26 |       map[event] = callback;
 27 |     }),
 28 |     removeEventListener: jest.fn()
 29 |   };
 30 | 
 31 |   afterEach(() => {
 32 |     Object.values(ectStatusListeners).forEach(listener => listener.mockClear());
 33 |   });
 34 | 
 35 |   /**
 36 |    * Tests that addEventListener or removeEventListener was called during the
 37 |    * lifecycle of the useEffect hook within useNetworkStatus
 38 |    */
 39 |   const testEctStatusEventListenerMethod = method => {
 40 |     expect(method).toBeCalledTimes(1);
 41 |     expect(method.mock.calls[0][0]).toEqual('change');
 42 |     expect(method.mock.calls[0][1].constructor).toEqual(Function);
 43 |   };
 44 | 
 45 |   test(`should return "true" for unsupported case`, () => {
 46 |     const { result } = renderHook(() => useNetworkStatus());
 47 | 
 48 |     expect(result.current.unsupported).toBe(true);
 49 |   });
 50 | 
 51 |   test('should return initialEffectiveConnectionType for unsupported case', () => {
 52 |     const initialEffectiveConnectionType = '4g';
 53 | 
 54 |     const { result } = renderHook(() =>
 55 |       useNetworkStatus(initialEffectiveConnectionType)
 56 |     );
 57 | 
 58 |     expect(result.current.unsupported).toBe(true);
 59 |     expect(result.current.effectiveConnectionType).toBe(
 60 |       initialEffectiveConnectionType
 61 |     );
 62 |   });
 63 | 
 64 |   test('should return 4g of effectiveConnectionType', () => {
 65 |     global.navigator.connection = {
 66 |       ...ectStatusListeners,
 67 |       effectiveType: '4g'
 68 |     };
 69 | 
 70 |     const { result } = renderHook(() => useNetworkStatus());
 71 | 
 72 |     testEctStatusEventListenerMethod(ectStatusListeners.addEventListener);
 73 |     expect(result.current.unsupported).toBe(false);
 74 |     expect(result.current.effectiveConnectionType).toEqual('4g');
 75 |   });
 76 | 
 77 |   test('should not return initialEffectiveConnectionType for supported case', () => {
 78 |     const initialEffectiveConnectionType = '2g';
 79 |     global.navigator.connection = {
 80 |       ...ectStatusListeners,
 81 |       effectiveType: '4g'
 82 |     };
 83 | 
 84 |     const { result } = renderHook(() =>
 85 |       useNetworkStatus(initialEffectiveConnectionType)
 86 |     );
 87 | 
 88 |     testEctStatusEventListenerMethod(ectStatusListeners.addEventListener);
 89 |     expect(result.current.unsupported).toBe(false);
 90 |     expect(result.current.effectiveConnectionType).toEqual('4g');
 91 |   });
 92 | 
 93 |   test('should update the effectiveConnectionType state', () => {
 94 |     const { result } = renderHook(() => useNetworkStatus());
 95 | 
 96 |     act(() =>
 97 |       result.current.setNetworkStatus({ effectiveConnectionType: '2g' })
 98 |     );
 99 | 
100 |     expect(result.current.effectiveConnectionType).toEqual('2g');
101 |   });
102 | 
103 |   test('should update the effectiveConnectionType state when navigator.connection change event', () => {
104 |     global.navigator.connection = {
105 |       ...ectStatusListeners,
106 |       effectiveType: '2g'
107 |     };
108 | 
109 |     const { result } = renderHook(() => useNetworkStatus());
110 |     global.navigator.connection.effectiveType = '4g';
111 |     act(() => map.change());
112 | 
113 |     expect(result.current.effectiveConnectionType).toEqual('4g');
114 |   });
115 | 
116 |   test('should remove the listener for the navigator.connection change event on unmount', () => {
117 |     global.navigator.connection = {
118 |       ...ectStatusListeners,
119 |       effectiveType: '2g'
120 |     };
121 | 
122 |     const { unmount } = renderHook(() => useNetworkStatus());
123 | 
124 |     testEctStatusEventListenerMethod(ectStatusListeners.addEventListener);
125 |     unmount();
126 |     testEctStatusEventListenerMethod(ectStatusListeners.removeEventListener);
127 |   });
128 | });
129 | 


--------------------------------------------------------------------------------
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/README.md:
--------------------------------------------------------------------------------
  1 | # React Adaptive Loading Hooks &amp; Utilities &middot; ![](https://img.shields.io/github/license/GoogleChromeLabs/react-adaptive-hooks.svg) [![Build Status](https://travis-ci.org/GoogleChromeLabs/react-adaptive-hooks.svg?branch=master)](https://travis-ci.org/GoogleChromeLabs/react-adaptive-hooks) ![npm bundle size](https://img.shields.io/bundlephobia/minzip/react-adaptive-hooks)
  2 | 
  3 | > Deliver experiences best suited to a user's device and network constraints (experimental)
  4 | 
  5 | This is a suite of [React Hooks](https://reactjs.org/docs/hooks-overview.html) and utilities for adaptive loading based on a user's:
  6 | 
  7 | * [Network via effective connection type](https://developer.mozilla.org/en-US/docs/Web/API/NetworkInformation/effectiveType)
  8 | * [Data Saver preferences](https://developer.mozilla.org/en-US/docs/Web/API/NetworkInformation/saveData)
  9 | * [Device memory](https://developer.mozilla.org/en-US/docs/Web/API/Navigator/deviceMemory)
 10 | * [Logical CPU cores](https://developer.mozilla.org/en-US/docs/Web/API/NavigatorConcurrentHardware/hardwareConcurrency)
 11 | * [Media Capabilities API](https://developer.mozilla.org/en-US/docs/Web/API/Media_Capabilities_API)
 12 | 
 13 | It can be used to add patterns for adaptive resource loading, data-fetching, code-splitting and capability toggling.
 14 | 
 15 | ## Objective
 16 | 
 17 | Make it easier to target low-end devices while progressively adding high-end-only features on top. Using these hooks and utilities can help you give users a great experience best suited to their device and network constraints.
 18 | 
 19 | ## Installation
 20 | 
 21 | `npm i react-adaptive-hooks --save` or `yarn add react-adaptive-hooks`
 22 | 
 23 | ## Usage
 24 | 
 25 | You can import the hooks you wish to use as follows:
 26 | 
 27 | ```js
 28 | import { useNetworkStatus } from 'react-adaptive-hooks/network';
 29 | import { useSaveData } from 'react-adaptive-hooks/save-data';
 30 | import { useHardwareConcurrency } from 'react-adaptive-hooks/hardware-concurrency';
 31 | import { useMemoryStatus } from 'react-adaptive-hooks/memory';
 32 | import { useMediaCapabilitiesDecodingInfo } from 'react-adaptive-hooks/media-capabilities';
 33 | ```
 34 | 
 35 | and then use them in your components. Examples for each hook and utility can be found below:
 36 | 
 37 | ### Network
 38 | 
 39 | `useNetworkStatus` React hook for adapting based on network status (effective connection type)
 40 | 
 41 | ```js
 42 | import React from 'react';
 43 | 
 44 | import { useNetworkStatus } from 'react-adaptive-hooks/network';
 45 | 
 46 | const MyComponent = () => {
 47 |   const { effectiveConnectionType } = useNetworkStatus();
 48 | 
 49 |   let media;
 50 |   switch(effectiveConnectionType) {
 51 |     case 'slow-2g':
 52 |       media = <img src='...' alt='low resolution' />;
 53 |       break;
 54 |     case '2g':
 55 |       media = <img src='...' alt='medium resolution' />;
 56 |       break;
 57 |     case '3g':
 58 |       media = <img src='...' alt='high resolution' />;
 59 |       break;
 60 |     case '4g':
 61 |       media = <video muted controls>...</video>;
 62 |       break;
 63 |     default:
 64 |       media = <video muted controls>...</video>;
 65 |       break;
 66 |   }
 67 |   
 68 |   return <div>{media}</div>;
 69 | };
 70 | ```
 71 | 
 72 | `effectiveConnectionType` values can be `slow-2g`, `2g`, `3g`, or `4g`.
 73 | 
 74 | This hook accepts an optional `initialEffectiveConnectionType` string argument, which can be used to provide a `effectiveConnectionType` state value when the user's browser does not support the relevant [NetworkInformation API](https://wicg.github.io/netinfo/). Passing an initial value can also prove useful for server-side rendering, where the developer can pass an [ECT Client Hint](https://developers.google.com/web/fundamentals/performance/optimizing-content-efficiency/client-hints#ect) to detect the effective network connection type.
 75 | 
 76 | ```js
 77 | // Inside of a functional React component
 78 | const initialEffectiveConnectionType = '4g';
 79 | const { effectiveConnectionType } = useNetworkStatus(initialEffectiveConnectionType);
 80 | ```
 81 | 
 82 | ### Save Data
 83 | 
 84 | `useSaveData` utility for adapting based on the user's browser Data Saver preferences.
 85 | 
 86 | ```js
 87 | import React from 'react';
 88 | 
 89 | import { useSaveData } from 'react-adaptive-hooks/save-data';
 90 | 
 91 | const MyComponent = () => {
 92 |   const { saveData } = useSaveData();
 93 |   return (
 94 |     <div>
 95 |       { saveData ? <img src='...' /> : <video muted controls>...</video> }
 96 |     </div>
 97 |   );
 98 | };
 99 | ```
100 | 
101 | `saveData` values can be `true` or `false`.
102 | 
103 | This hook accepts an optional `initialSaveData` boolean argument, which can be used to provide a `saveData` state value when the user's browser does not support the relevant [NetworkInformation API](https://wicg.github.io/netinfo/). Passing an initial value can also prove useful for server-side rendering, where the developer can pass a server [Save-Data Client Hint](https://developers.google.com/web/fundamentals/performance/optimizing-content-efficiency/client-hints#save-data) that has been converted to a boolean to detect the user's data saving preference.
104 | 
105 | ```js
106 | // Inside of a functional React component
107 | const initialSaveData = true;
108 | const { saveData } = useSaveData(initialSaveData);
109 | ```
110 | 
111 | ### CPU Cores / Hardware Concurrency
112 | 
113 | `useHardwareConcurrency` utility for adapting to the number of logical CPU processor cores on the user's device.
114 | 
115 | ```js
116 | import React from 'react';
117 | 
118 | import { useHardwareConcurrency } from 'react-adaptive-hooks/hardware-concurrency';
119 | 
120 | const MyComponent = () => {
121 |   const { numberOfLogicalProcessors } = useHardwareConcurrency();
122 |   return (
123 |     <div>
124 |       { numberOfLogicalProcessors <= 4 ? <img src='...' /> : <video muted controls>...</video> }
125 |     </div>
126 |   );
127 | };
128 | ```
129 | 
130 | `numberOfLogicalProcessors` values can be the number of logical processors available to run threads on the user's device. 
131 | 
132 | ### Memory
133 | 
134 | `useMemoryStatus` utility for adapting based on the user's device memory (RAM)
135 | 
136 | ```js
137 | import React from 'react';
138 | 
139 | import { useMemoryStatus } from 'react-adaptive-hooks/memory';
140 | 
141 | const MyComponent = () => {
142 |   const { deviceMemory } = useMemoryStatus();
143 |   return (
144 |     <div>
145 |       { deviceMemory < 4 ? <img src='...' /> : <video muted controls>...</video> }
146 |     </div>
147 |   );
148 | };
149 | ```
150 | 
151 | `deviceMemory` values can be the approximate amount of device memory in gigabytes.
152 | 
153 | This hook accepts an optional `initialMemoryStatus` object argument, which can be used to provide a `deviceMemory` state value when the user's browser does not support the relevant [DeviceMemory API](https://github.com/w3c/device-memory). Passing an initial value can also prove useful for server-side rendering, where the developer can pass a server [Device-Memory Client Hint](https://developers.google.com/web/fundamentals/performance/optimizing-content-efficiency/client-hints#save-data) to detect the memory capacity of the user's device.
154 | 
155 | ```js
156 | // Inside of a functional React component
157 | const initialMemoryStatus = { deviceMemory: 4 };
158 | const { deviceMemory } = useMemoryStatus(initialMemoryStatus);
159 | ```
160 | 
161 | ### Media Capabilities
162 | 
163 | `useMediaCapabilitiesDecodingInfo` utility for adapting based on the user's device media capabilities.
164 | 
165 | **Use case:** this hook can be used to check if we can play a certain content type. For example, Safari does not support WebM so we want to fallback to MP4 but if Safari at some point does support WebM it will automatically load WebM videos.
166 | 
167 | ```js
168 | import React from 'react';
169 | 
170 | import { useMediaCapabilitiesDecodingInfo } from 'react-adaptive-hooks/media-capabilities';
171 | 
172 | const webmMediaDecodingConfig = {
173 |   type: 'file', // 'record', 'transmission', or 'media-source'
174 |   video: {
175 |     contentType: 'video/webm;codecs=vp8', // valid content type
176 |     width: 800, // width of the video
177 |     height: 600, // height of the video
178 |     bitrate: 10000, // number of bits used to encode 1s of video
179 |     framerate: 30 // number of frames making up that 1s.
180 |   }
181 | };
182 | 
183 | const initialMediaCapabilitiesInfo = { powerEfficient: true };
184 | 
185 | const MyComponent = ({ videoSources }) => {
186 |   const { mediaCapabilitiesInfo } = useMediaCapabilitiesDecodingInfo(webmMediaDecodingConfig, initialMediaCapabilitiesInfo);
187 | 
188 |   return (
189 |     <div>
190 |       <video src={mediaCapabilitiesInfo.supported ? videoSources.webm : videoSources.mp4} controls>...</video>
191 |     </div>
192 |   );
193 | };
194 | ```
195 | 
196 | `mediaCapabilitiesInfo` value contains the three Boolean properties supported, smooth, and powerEfficient, which describe whether decoding the media described would be supported, smooth, and powerEfficient.
197 | 
198 | This utility accepts a [MediaDecodingConfiguration](https://developer.mozilla.org/en-US/docs/Web/API/MediaDecodingConfiguration) object argument and an optional `initialMediaCapabilitiesInfo` object argument, which can be used to provide a `mediaCapabilitiesInfo` state value when the user's browser does not support the relevant [Media Capabilities API](https://developer.mozilla.org/en-US/docs/Web/API/Media_Capabilities_API) or no media configuration was given.
199 | 
200 | ### Adaptive Code-loading & Code-splitting
201 | 
202 | #### Code-loading
203 | 
204 | Deliver a light, interactive core experience to users and progressively add high-end-only features on top, if a user's hardware can handle it. Below is an example using the Network Status hook:
205 | 
206 | ```js
207 | import React, { Suspense, lazy } from 'react';
208 | 
209 | import { useNetworkStatus } from 'react-adaptive-hooks/network';
210 | 
211 | const Full = lazy(() => import(/* webpackChunkName: "full" */ './Full.js'));
212 | const Light = lazy(() => import(/* webpackChunkName: "light" */ './Light.js'));
213 | 
214 | const MyComponent = () => {
215 |   const { effectiveConnectionType } = useNetworkStatus();
216 |   return (
217 |     <div>
218 |       <Suspense fallback={<div>Loading...</div>}>
219 |         { effectiveConnectionType === '4g' ? <Full /> : <Light /> }
220 |       </Suspense>
221 |     </div>
222 |   );
223 | };
224 | 
225 | export default MyComponent;
226 | ```
227 | 
228 | Light.js:
229 | ```js
230 | import React from 'react';
231 | 
232 | const Light = ({ imageUrl, ...rest }) => (
233 |   <img src={imageUrl} {...rest} />
234 | );
235 | 
236 | export default Light;
237 | ```
238 | 
239 | Full.js:
240 | ```js
241 | import React from 'react';
242 | import Magnifier from 'react-magnifier';
243 | 
244 | const Full = ({ imageUrl, ...rest }) => (
245 |   <Magnifier src={imageUrl} {...rest} />
246 | );
247 | 
248 | export default Full;
249 | ```
250 | 
251 | #### Code-splitting
252 | 
253 | We can extend `React.lazy()` by incorporating a check for a device or network signal. Below is an example of network-aware code-splitting. This allows us to conditionally load a light core experience or full-fat experience depending on the user's effective connection speed (via `navigator.connection.effectiveType`).
254 | 
255 | ```js
256 | import React, { Suspense } from 'react';
257 | 
258 | const Component = React.lazy(() => {
259 |   const effectiveType = navigator.connection ? navigator.connection.effectiveType : null
260 | 
261 |   let module;
262 |   switch (effectiveType) {
263 |     case '3g':
264 |       module = import(/* webpackChunkName: "light" */ './Light.js');
265 |       break;
266 |     case '4g':
267 |       module = import(/* webpackChunkName: "full" */ './Full.js');
268 |       break;
269 |     default:
270 |       module = import(/* webpackChunkName: "full" */ './Full.js');
271 |       break;
272 |   }
273 | 
274 |   return module;
275 | });
276 | 
277 | const App = () => {
278 |   return (
279 |     <div className='App'>
280 |       <Suspense fallback={<div>Loading...</div>}>
281 |         <Component />
282 |       </Suspense>
283 |     </div>
284 |   );
285 | };
286 | 
287 | export default App;
288 | ```
289 | 
290 | ## Server-side rendering support
291 | 
292 | The built version of this package uses ESM (native JS modules) by default, but is not supported on the server-side. When using this package in a web framework like Next.js with server-rendering, we recommend you
293 | 
294 | * Transpile the package by installing [next-transpile-modules](https://github.com/martpie/next-transpile-modules). ([example project](https://github.com/GoogleChromeLabs/adaptive-loading/tree/master/next-show-adaptive-loading)). This is because Next.js currently does not pass `node_modules` into webpack server-side.
295 | 
296 | * Use a UMD build as in the following code-snippet: ([example project](https://glitch.com/edit/#!/anton-karlovskiy-next-show-adaptive-loading?path=utils/hooks.js:19:91))
297 | ```
298 | import {
299 |   useNetworkStatus,
300 |   useSaveData,
301 |   useHardwareConcurrency,
302 |   useMemoryStatus,
303 |   useMediaCapabilitiesDecodingInfo
304 | } from 'react-adaptive-hooks/dist/index.umd.js';
305 | ```
306 | 
307 | ## Browser Support
308 | 
309 | * [Network Information API - effectiveType](https://developer.mozilla.org/en-US/docs/Web/API/NetworkInformation/effectiveType) is available in [Chrome 61+, Opera 48+, Edge 76+, Chrome for Android 76+, Firefox for Android 68+](https://caniuse.com/#search=effectiveType)
310 | 
311 | * [Save Data API](https://developer.mozilla.org/en-US/docs/Web/API/NetworkInformation/saveData) is available in [Chrome 65+, Opera 62+, Chrome for Android 76+, Opera for Android 46+](https://caniuse.com/#search=saveData)
312 | 
313 | * [Hardware Concurrency API](https://developer.mozilla.org/en-US/docs/Web/API/NavigatorConcurrentHardware/hardwareConcurrency) is available in [Chrome 37+, Safari 10.1+, Firefox 48+, Opera 24+, Edge 15+, Chrome for Android 76+, Safari on iOS 10.3+, Firefox for Android 68+, Opera for Android 46+](https://caniuse.com/#search=navigator.hardwareConcurrency)
314 | 
315 | * [Performance memory API](https://developer.mozilla.org/en-US/docs/Web/API/Performance) is a non-standard and only available in [Chrome 7+, Opera, Chrome for Android 18+, Opera for Android](https://developer.mozilla.org/en-US/docs/Web/API/Performance/memory)
316 | 
317 | * [Device Memory API](https://developer.mozilla.org/en-US/docs/Web/API/Navigator/deviceMemory) is available in [Chrome 63+, Opera 50+, Chrome for Android 76+, Opera for Android 46+](https://caniuse.com/#search=deviceMemory)
318 | 
319 | * [Media Capabilities API](https://developer.mozilla.org/en-US/docs/Web/API/Media_Capabilities_API) is available in [Chrome 63+, Firefox 63+, Opera 55+, Chrome for Android 78+, Firefox for Android 68+](https://caniuse.com/#search=media%20capabilities)
320 | 
321 | ## Demos
322 | 
323 | ### Network
324 | 
325 | * [Network-aware loading](https://github.com/GoogleChromeLabs/adaptive-loading/tree/master/cra-network-aware-loading) with create-react-app ([Live](https://adaptive-loading.web.app/cra-network-aware-loading/))
326 | * [Network-aware code-splitting](https://github.com/GoogleChromeLabs/adaptive-loading/tree/master/cra-network-aware-code-splitting) with create-react-app ([Live](https://adaptive-loading.web.app/cra-network-aware-code-splitting/))
327 | * [Network-aware data-fetching](https://github.com/GoogleChromeLabs/adaptive-loading/tree/master/cra-network-aware-data-fetching) with create-react-app ([Live](https://adaptive-loading.web.app/cra-network-aware-data-fetching/))
328 | 
329 | * [React Movie - network-aware loading](https://github.com/GoogleChromeLabs/adaptive-loading/tree/master/react-movie-network-aware-loading) ([Live](https://adaptive-loading.web.app/react-movie-network-aware-loading/))
330 | * [React Shrine - network-aware code-splitting](https://github.com/GoogleChromeLabs/adaptive-loading/tree/master/react-shrine-network-aware-code-splitting) ([Live](https://adaptive-loading.web.app/react-shrine-network-aware-code-splitting/))
331 | * [React eBay - network-aware code-splitting](https://github.com/GoogleChromeLabs/adaptive-loading/tree/master/react-ebay-network-aware-code-splitting) ([Live](https://adaptive-loading.web.app/react-ebay-network-aware-code-splitting/))
332 | * [React Lottie - network-aware loading](https://github.com/GoogleChromeLabs/adaptive-loading/tree/master/react-lottie-network-aware-loading) ([Live](https://adaptive-loading.web.app/react-lottie-network-aware-loading/))
333 | 
334 | ### Save Data
335 | 
336 | * [React Twitter - save-data loading based on Client Hint](https://github.com/GoogleChromeLabs/adaptive-loading/tree/master/react-twitter-save-data-loading(client-hint)) ([Live](https://adaptive-loading.web.app/react-twitter-save-data-loading(client-hint)/))
337 | * [React Twitter - save-data loading based on Hook](https://github.com/GoogleChromeLabs/adaptive-loading/tree/master/react-twitter-save-data-loading(hook)) ([Live](https://adaptive-loading.web.app/react-twitter-save-data-loading(hook)/))
338 | 
339 | ### CPU Cores / Hardware Concurrency
340 | 
341 | * [Hardware concurrency considerate code-splitting](https://github.com/GoogleChromeLabs/adaptive-loading/tree/master/cra-hardware-concurrency-considerate-code-splitting) with create-react-app ([Live](https://adaptive-loading.web.app/cra-hardware-concurrency-considerate-code-splitting/))
342 | * [Hardware concurrency considerate loading](https://github.com/GoogleChromeLabs/adaptive-loading/tree/master/cra-hardware-concurrency-considerate-loading) with create-react-app ([Live](https://adaptive-loading.web.app/cra-hardware-concurrency-considerate-loading/))
343 | 
344 | ### Memory
345 | 
346 | * [Memory considerate loading](https://github.com/GoogleChromeLabs/adaptive-loading/tree/master/cra-memory-considerate-loading) with create-react-app ([Live](https://adaptive-loading.web.app/cra-memory-considerate-loading/))
347 | * [Memory considerate loading (SketchFab version)](https://github.com/GoogleChromeLabs/adaptive-loading/tree/master/cra-memory-considerate-loading-sketchfab) with create-react-app ([Live](https://adaptive-loading.web.app/cra-memory-considerate-loading-sketchfab/))
348 | * [Memory-considerate animation-toggling](https://github.com/GoogleChromeLabs/adaptive-loading/tree/master/cna-memory-considerate-animation) with create-next-app ([Live](https://adaptive-loading.web.app/cna-memory-considerate-animation/))
349 | 
350 | * [React Dixie Mesh - memory considerate loading](https://github.com/GoogleChromeLabs/adaptive-loading/tree/master/react-dixie-memory-considerate-loading) ([Live](https://adaptive-loading.web.app/react-dixie-memory-considerate-loading/))
351 | 
352 | ### Hybrid
353 | 
354 | * [React Youtube - adaptive loading with mix of network, memory and hardware concurrency](https://github.com/GoogleChromeLabs/adaptive-loading/tree/master/react-youtube-adaptive-loading) ([Live](https://adaptive-loading.web.app/react-youtube-adaptive-loading/))
355 | * [Next Show - adaptive loading with mix of network, memory and Client Hints](https://github.com/GoogleChromeLabs/adaptive-loading/tree/master/next-show-adaptive-loading) ([demo](https://adaptive-loading.web.app/next-show-adaptive-loading/))
356 | 
357 | ## References
358 | 
359 | * [Adaptive serving based on network quality](https://web.dev/adaptive-serving-based-on-network-quality/)
360 | * [Adaptive Serving using JavaScript and the Network Information API](https://addyosmani.com/blog/adaptive-serving/)
361 | * [Serving Adaptive Components Using the Network Information API](https://dev.to/vorillaz/serving-adaptive-components-using-the-network-information-api-lbo)
362 | 
363 | ## License
364 | 
365 | Licensed under the Apache-2.0 license.
366 | 
367 | ## Team
368 | 
369 | This project is brought to you by [Addy Osmani](https://github.com/addyosmani) and [Anton Karlovskiy](https://github.com/anton-karlovskiy).
370 | 


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