├── .babelrc ├── .gitignore ├── .npmignore ├── .travis.yml ├── LICENSE ├── README.md ├── package.json ├── src └── index.js ├── tests ├── create-multi-context.spec.js └── static-with.spec.js ├── webpack.config.js └── yarn.lock /.babelrc: -------------------------------------------------------------------------------- 1 | { 2 | "presets": [ "@babel/preset-env", "@babel/preset-react" ], 3 | "plugins": [ 4 | "@babel/plugin-proposal-class-properties", 5 | "@babel/plugin-proposal-object-rest-spread" 6 | ] 7 | } 8 | -------------------------------------------------------------------------------- /.gitignore: -------------------------------------------------------------------------------- 1 | /.git 2 | /.vscode 3 | /node_modules 4 | /index.js 5 | /yarn-error.log 6 | -------------------------------------------------------------------------------- /.npmignore: -------------------------------------------------------------------------------- 1 | /.git 2 | /.vscode 3 | /node_modules 4 | /src 5 | /.babelrc 6 | /.gitignore 7 | /.npmignore 8 | /package-lock.json 9 | /webpack.config.js 10 | /yarn.lock 11 | /yarn-error.log 12 | -------------------------------------------------------------------------------- /.travis.yml: -------------------------------------------------------------------------------- 1 | language: node_js 2 | node_js: 8.9.1 3 | branches: 4 | only: master 5 | cache: yarn 6 | install: yarn 7 | script: 8 | - yarn build 9 | - yarn test 10 | deploy: 11 | api_key: 12 | secure: 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 13 | email: npmjs@charlesstover.com 14 | on: 15 | branch: master 16 | provider: npm 17 | skip_cleanup: true 18 | -------------------------------------------------------------------------------- /LICENSE: -------------------------------------------------------------------------------- 1 | MIT License 2 | 3 | Copyright (c) 2018 Charles Stover 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 | -------------------------------------------------------------------------------- /README.md: -------------------------------------------------------------------------------- 1 | # React Multi-Context [![Tweet](https://img.shields.io/twitter/url/http/shields.io.svg?style=social)](https://twitter.com/intent/tweet?text=Simplify%20React's%20Context%20API%20by%20managing%20multiple%20contexts%20with%20a%20single%20component.&url=https://github.com/CharlesStover/react-multi-context&via=CharlesStover&hashtags=react,reactjs,javascript,webdev,webdeveloper,webdevelopment) 2 | 3 | Manage multiple contexts with a single React component. 4 | 5 | [![version](https://img.shields.io/npm/v/react-multi-context.svg)](https://www.npmjs.com/package/react-multi-context) 6 | [![minified size](https://img.shields.io/bundlephobia/min/react-multi-context.svg)](https://www.npmjs.com/package/react-multi-context) 7 | [![minzipped size](https://img.shields.io/bundlephobia/minzip/react-multi-context.svg)](https://www.npmjs.com/package/react-multi-context) 8 | [![downloads](https://img.shields.io/npm/dt/react-multi-context.svg)](https://www.npmjs.com/package/react-multi-context) 9 | [![build](https://api.travis-ci.com/CharlesStover/react-multi-context.svg)](https://travis-ci.com/CharlesStover/react-multi-context/) 10 | 11 | ## Install 12 | 13 | * `npm install react-multi-context --save` or 14 | * `yarn add react-multi-context` 15 | 16 | ## Test 17 | 18 | * `npm run test` or 19 | * `yarn test` 20 | 21 | ## Use 22 | 23 | ```JS 24 | import createMultiContext from 'react-multi-context'; 25 | export const MyMultiContext = createMultiContext(); 26 | ``` 27 | 28 | Create the context by importing and executing `createMultiContext` wherever you want to create context. 29 | Then, import that multi-context instance as needed. 30 | 31 | Use the `set` prop to set a context's value. 32 | Changing the value on a key-value pair in a context will cause all getters for that key to re-render. 33 | 34 | Use the `get` prop to get a context's value. 35 | Using this prop will execute the `children` render prop by passing the corresponding values of the context as the parameters. 36 | 37 | ## Example 38 | 39 | ```JS 40 | // Parent.js 41 | import createMultiContext from 'react-multi-context'; 42 | 43 | // Context to provide to children. 44 | export const ParentContext = createMultiContext(); 45 | 46 | export default class Parent extends React.Component { 47 | render() { 48 | return ( 49 | 59 | 60 | 61 | ); 62 | } 63 | } 64 | ``` 65 | ```JS 66 | // Child.js 67 | // Get the context provided from the parent 68 | import { ParentContext } from './Parent'; 69 | 70 | export default class Child extends React.Component { 71 | render() { 72 | return ( 73 | 74 | {(project, user) => 75 | 76 | /* This is a demo of React Multi-Context v1.0 by Charles! */ 77 |

This is a demo of {project.name} v{project.version} by {user}!

78 | } 79 | 80 | ); 81 | } 82 | } 83 | ``` 84 | 85 | ## Example (Shorter) 86 | 87 | ```JS 88 | // Parent - writes A and B 89 | const Parent = () => 90 | 91 | 92 | 93 | 94 | ; 95 | ``` 96 | ```JS 97 | // Child1 - reads A 98 | // Note: Each value is its own context, which is what makes this MULTI-context. 99 | const Child1 = () => 100 | 101 | {(a) => `The value of A is ${a}!`} 102 | ; 103 | ``` 104 | ```JS 105 | // Child2 - reads A and B 106 | // Note: Reading multiple values will trigger a re-render if any one read value changes. 107 | const Child2 = () => 108 | 109 | {(a, b) => `The value of A+B is ${a + b}!`} 110 | ; 111 | ``` 112 | ```JS 113 | // Child3 - reads B and A 114 | // Note: The order of the get prop corresponds to the order of the function parameters. 115 | const Child3 = () => 116 | 117 | {(b, a) => `The value of A+B is ${a + b}!`} 118 | ; 119 | ``` 120 | 121 | ## Default Values 122 | 123 | You may pass an object of default values for the contexts as a parameter to `createMultiContext` or via the `default` prop. 124 | 125 | ```JS 126 | const MyMultiContext = createMultiContext({ a: 0, b: 0 }); 127 | ``` 128 | 129 | or 130 | 131 | ```JS 132 | 136 | 137 | {b => 'I predict that B equals zero: ' + b} 138 | 139 | 140 | ``` 141 | 142 | You do not need to do both. 143 | 144 | ## MultiContext.with 145 | 146 | `MultiContextInstance.with(...multiContextKeys)(Component)` will bind the `multiContextKeys` of `MultiContextInstance` to the props of `Component`. 147 | 148 | ```JS 149 | import React from 'react'; 150 | import { SomeMultiContext } from './some-component'; 151 | 152 | class MyComponent extends React.PureComponent { 153 | render() { 154 | return
; 155 | } 156 | } 157 | 158 | // Binds the MultiContext's `name` property to MyComponent's `name` prop. 159 | export default SomeMultiContext.with('name', 'age')(MyComponent); 160 | ``` 161 | 162 | ## Sponsor 💗 163 | 164 | If you are a fan of this project, you may 165 | [become a sponsor](https://github.com/sponsors/CharlesStover) 166 | via GitHub's Sponsors Program. 167 | -------------------------------------------------------------------------------- /package.json: -------------------------------------------------------------------------------- 1 | { 2 | "name": "react-multi-context", 3 | "version": "1.1.2", 4 | "author": "Charles Stover", 5 | "bugs": { 6 | "url": "https://github.com/CharlesStover/react-multi-context/issues" 7 | }, 8 | "description": "Manage multiple contexts with a single React component.", 9 | "devDependencies": { 10 | "@babel/core": "^7.0.0-beta.53", 11 | "@babel/plugin-proposal-class-properties": "^7.0.0-rc.0", 12 | "@babel/plugin-proposal-object-rest-spread": "^7.0.0-beta.53", 13 | "@babel/preset-env": "^7.0.0-beta.53", 14 | "@babel/preset-react": "^7.0.0-beta.54", 15 | "babel-core": "^7.0.0-bridge.0", 16 | "babel-jest": "^23.4.0", 17 | "babel-loader": "^8.0.0-beta.4", 18 | "enzyme": "^3.3.0", 19 | "enzyme-adapter-react-16": "^1.2.0", 20 | "jest": "^24.8.0", 21 | "react": "^16.0.0", 22 | "react-dom": "^16.4.1", 23 | "webpack": "^4.16.0", 24 | "webpack-cli": "^3.0.8" 25 | }, 26 | "homepage": "https://github.com/CharlesStover/react-multi-context#readme", 27 | "keywords": [ 28 | "react", 29 | "reactjs", 30 | "context" 31 | ], 32 | "license": "MIT", 33 | "main": "index.js", 34 | "peerDependencies": { 35 | "react": "^16.0.0" 36 | }, 37 | "repository": { 38 | "type": "git", 39 | "url": "git+https://github.com/CharlesStover/react-multi-context.git" 40 | }, 41 | "scripts": { 42 | "build": "webpack", 43 | "prepublishOnly": "npm run build", 44 | "test": "jest tests/.+.spec.js" 45 | } 46 | } 47 | -------------------------------------------------------------------------------- /src/index.js: -------------------------------------------------------------------------------- 1 | import React from 'react'; 2 | 3 | const providerSort = (a, b) => 4 | a[0] < b[0] ? 5 | -1 : 6 | 1; 7 | 8 | const createMultiContext = (defaults = Object.create(null)) => { 9 | const contexts = Object.create(null); 10 | for (const [ key, value ] of Object.entries(defaults)) { 11 | contexts[key] = React.createContext(value); 12 | } 13 | 14 | return class MultiContext extends React.PureComponent { 15 | 16 | static with(...contextKeys) { 17 | 18 | const reduceContextToProps = (props, contextValue, index) => { 19 | props[contextKeys[index]] = contextValue; 20 | return props; 21 | }; 22 | 23 | return (Component) => 24 | class WithMultiContext extends React.PureComponent { 25 | 26 | contextConsumer = (...contextValues) => { 27 | const props = contextValues.reduce( 28 | reduceContextToProps, 29 | Object.create(null) 30 | ); 31 | return ( 32 | 36 | ); 37 | } 38 | 39 | render() { 40 | return ( 41 | 45 | ); 46 | } 47 | }; 48 | } 49 | 50 | createContext(key) { 51 | if (!Object.prototype.hasOwnProperty.call(contexts, key)) { 52 | contexts[key] = 53 | typeof this.props.default === 'object' && 54 | this.props.default !== null && 55 | Object.prototype.hasOwnProperty.call(this.props.default, key) ? 56 | React.createContext(this.props.default[key]) : 57 | React.createContext(); 58 | } 59 | return contexts[key]; 60 | } 61 | 62 | // Recursively generate , with each consumer being a child of the last. 63 | getConsumer(children, index, values) { 64 | 65 | // If we have all the consumers, we can spread the values to the child render prop. 66 | if (this.props.get.length === index) { 67 | return children(...values); 68 | } 69 | 70 | // Check if this context exists. 71 | const contextKey = this.props.get[index]; 72 | if (!Object.prototype.hasOwnProperty.call(contexts, contextKey)) { 73 | throw new Error('Context `' + contextKey + '` does not exist.'); 74 | } 75 | 76 | // Create this context's consumer. 77 | const Context = contexts[contextKey]; 78 | return ( 79 | 82 | this.getConsumer( 83 | children, 84 | index + 1, 85 | values.concat([ value ]) 86 | ) 87 | } 88 | /> 89 | ); 90 | } 91 | 92 | getProvider(children, providers, index) { 93 | 94 | // If we have all the consumers, we can spread the values to the child render prop. 95 | if (providers.length === index) { 96 | return children; 97 | } 98 | 99 | // Create the context (if it doesn't exist). 100 | const Context = this.createContext(providers[index][0]); 101 | 102 | // Create this context's provider. 103 | return ( 104 | 108 | ); 109 | } 110 | 111 | get hasConsumers() { 112 | return ( 113 | Array.isArray(this.props.get) && 114 | this.props.get.length > 0 115 | ); 116 | } 117 | 118 | get hasProviders() { 119 | return ( 120 | typeof this.props.set === 'object' && 121 | this.props.set !== null 122 | ); 123 | } 124 | 125 | renderConsumers(children) { 126 | 127 | // If there are no consumers to get, just return the children. 128 | if (!this.hasConsumers) { 129 | return children; 130 | } 131 | 132 | // If there are consumers to get, get them one at a time. 133 | if (typeof children !== 'function') { 134 | throw new Error('Consuming context requires a function child.'); 135 | } 136 | 137 | return this.getConsumer(children, 0, []); 138 | } 139 | 140 | renderProviders(children) { 141 | 142 | // If there are no providers to set, just return the children. 143 | if (!this.hasProviders) { 144 | return children; 145 | } 146 | 147 | // If there are providers to set, 148 | const providers = Object.entries(this.props.set); 149 | if ( 150 | typeof this.props.default === 'object' && 151 | this.props.default !== null 152 | ) { 153 | const propDefaults = Object.entries(this.props.default); 154 | const propDefaultsLength = propDefaults.length; 155 | for (let x = 0; x < propDefaultsLength; x++) { 156 | 157 | // Don't duplicate a provider if it is already set. 158 | if (!Object.prototype.hasOwnProperty.call(this.props.set, propDefaults[x][0])) { 159 | providers.push(propDefaults[x]); 160 | } 161 | } 162 | } 163 | if (providers.length === 0) { 164 | return children; 165 | } 166 | 167 | // Sort them to insure same hierarchy and prevent unnecessary re-rendering (if hierarchy were to change). 168 | providers.sort(providerSort); 169 | 170 | // If there are consumers, return a function render prop that sets each provider one at a time. 171 | if (this.hasConsumers) { 172 | return (...values) => this.getProvider(children(...values), providers, 0); 173 | } 174 | 175 | // If there are no consumers, set each provider one at a time. 176 | return this.getProvider(children, providers, 0); 177 | } 178 | 179 | render() { 180 | return this.renderConsumers( 181 | this.renderProviders( 182 | this.props.children 183 | ) 184 | ); 185 | } 186 | }; 187 | }; 188 | 189 | export default createMultiContext; 190 | -------------------------------------------------------------------------------- /tests/create-multi-context.spec.js: -------------------------------------------------------------------------------- 1 | import Enzyme, { mount, shallow } from 'enzyme'; 2 | import Adapter from 'enzyme-adapter-react-16'; 3 | import React from 'react'; 4 | import createMultiContext from '../index'; 5 | 6 | Enzyme.configure({ adapter: new Adapter() }); 7 | 8 | describe('createMultiContext', () => { 9 | 10 | let MultiContext = null; 11 | beforeEach(() => { 12 | MultiContext = createMultiContext({ d: true }); 13 | }); 14 | 15 | it('should render without crashing', () => { 16 | shallow(); 17 | }); 18 | 19 | it.skip('should not render contexts without getters/setters', () => { 20 | const multiContext = shallow(); 21 | expect(multiContext.find('Context').length).toBe(0); 22 | }); 23 | 24 | 25 | 26 | // Set 27 | describe('set', () => { 28 | 29 | it('should accept an object', () => { 30 | expect(() => { 31 | shallow(); 32 | }).not.toThrowError(); 33 | }); 34 | }); 35 | 36 | 37 | 38 | // Get 39 | describe('get', () => { 40 | 41 | it('should accept an array and a render prop', () => { 42 | shallow(); 43 | expect(() => { 44 | shallow( 45 | null} 47 | get={[ 'a' ]} 48 | /> 49 | ); 50 | }).not.toThrowError(); 51 | }); 52 | 53 | it('should require a render prop', () => { 54 | shallow(); 55 | expect(() => { 56 | shallow( 57 | 61 | ); 62 | }).toThrowError(); 63 | expect(() => { 64 | shallow( 65 | 69 | ); 70 | }).toThrowError(); 71 | expect(() => { 72 | shallow( 73 | 77 | ); 78 | }).toThrowError(); 79 | }); 80 | 81 | it('should execute the render prop', () => { 82 | let value = null; 83 | mount( 84 | 85 | 86 | {a => { 87 | value = a; 88 | return null; 89 | }} 90 | 91 | 92 | ); 93 | expect(value).toBe(1); 94 | }); 95 | }); 96 | 97 | 98 | 99 | // Defaults 100 | describe('default', () => { 101 | it('should accept default parameter', () => { 102 | let value = null; 103 | mount( 104 | { 106 | value = d; 107 | return null; 108 | }} 109 | get={[ 'd' ]} 110 | /> 111 | ); 112 | expect(value).toBe(true); 113 | }); 114 | }); 115 | 116 | 117 | 118 | // Set + Get 119 | describe('set + get', () => { 120 | 121 | it('should not get what was just set', () => { 122 | let value = null; 123 | mount( 124 | { 126 | value = d; 127 | return null; 128 | }} 129 | get={[ 'd' ]} 130 | set={{ d: false }} 131 | /> 132 | ); 133 | expect(value).toBe(true); 134 | }); 135 | }); 136 | }); 137 | -------------------------------------------------------------------------------- /tests/static-with.spec.js: -------------------------------------------------------------------------------- 1 | import React from 'react'; 2 | import createMultiContext from '../index'; 3 | 4 | describe('static with', () => { 5 | 6 | let MultiContext = null; 7 | beforeEach(() => { 8 | MultiContext = createMultiContext(); 9 | }); 10 | 11 | it('should be a static method', () => { 12 | const hoc = MultiContext.with('name'); 13 | }); 14 | 15 | it('should return a Higher Order Component', () => { 16 | const hoc = MultiContext.with('name'); 17 | if (typeof hoc !== 'function') { 18 | throw new Error('Returned a ' + (typeof hoc) + ' (' + hoc + ')'); 19 | } 20 | }); 21 | }); 22 | -------------------------------------------------------------------------------- /webpack.config.js: -------------------------------------------------------------------------------- 1 | const path = require('path'); 2 | 3 | module.exports = { 4 | entry: './src/index.js', 5 | externals: { 6 | 'react': { 7 | amd: 'react', 8 | commonjs: 'react', 9 | commonjs2: 'react', 10 | root: 'React' 11 | } 12 | }, 13 | mode: 'production', 14 | module: { 15 | rules: [ 16 | { 17 | test: /\.js$/, 18 | use: { 19 | loader: 'babel-loader' 20 | } 21 | } 22 | ] 23 | }, 24 | output: { 25 | filename: 'index.js', 26 | library: 'react-multi-context', 27 | libraryTarget: 'umd', 28 | path: path.resolve(__dirname, '.'), 29 | umdNamedDefine: true 30 | }, 31 | resolve: { 32 | alias: { 33 | 'react': path.resolve(__dirname, './node_modules/react') 34 | } 35 | } 36 | }; 37 | --------------------------------------------------------------------------------