gitbook/packages/gitbook-core/src/lib/createContext.js

/* eslint-disable no-console */
const Redux = require('redux');
const ReduxThunk = require('redux-thunk').default;

const Plugin = require('../models/Plugin');
const Context = require('../models/Context');
const coreReducers = require('../reducers');
const composeReducer = require('./composeReducer');

const Components = require('../actions/components');
const I18n = require('../actions/i18n');
const History = require('../actions/history');

const isBrowser = (typeof window !== 'undefined');

/**
 * The core plugin defines the defualt behaviour of GitBook and provides
 * actions to other plugins.
 * @type {Plugin}
 */
const corePlugin = new Plugin({
    reduce: coreReducers,
    actions: {
        Components, I18n, History
    }
});

/**
 * Create a new context containing redux store from an initial state and a list of plugins.
 * Each plugin entry is the result of {createPlugin}.
 *
 * @param  {Array<Plugin>} plugins
 * @param  {Object} initialState
 * @return {Context} context
 */
function createContext(plugins, initialState) {
    plugins = [corePlugin].concat(plugins);

    // Compose the reducer from core with plugins
    const pluginReducers = plugins.map(plugin => plugin.reduce);
    const reducer = composeReducer(...pluginReducers);

    // Get actions from all plugins
    const actions = plugins.reduce((accu, plugin) => {
        return Object.assign(accu, plugin.actions);
    }, {});

    // Create thunk middleware which include actions
    const thunk = ReduxThunk.withExtraArgument(actions);

    // Create the redux store
    const store = Redux.createStore(
        (state, action) => {
            if (isBrowser) {
                console.log('[store]', action.type);
            }
            return reducer(state, action);
        },
        initialState,
        Redux.compose(Redux.applyMiddleware(thunk))
    );

    // Create the context
    const context = new Context({
        store,
        plugins,
        actions
    });

    // Initialize the plugins
    context.activate();

    return context;
}

module.exports = createContext;