Higher-order versions the functions Dan Abramov demos in the Egghead series Building React Applications with Idiomatic Redux

higher-order-storage.js

/**
 * Higher-order versions the functions Dan Abramov demos in the Egghead series:
 * Building React Applications with Idiomatic Redux
 * https://egghead.io/lessons/javascript-redux-persisting-the-state-to-the-local-storage
 * https://github.com/gaearon/todos/blob/03-persisting-state-to-local-storage/src/localStorage.js
 */

export const createLoadStateFor = (storage) => () => {
    try {
        const serializedState = storage.getItem('state');
        if (serializedState === null) {
            return undefined;
        }
        return JSON.parse(serializedState);
    } catch (err) {
        return undefined;
    }
};

export const createSaveStateFor = (storage) => (state) => {
    try {
        const serializedState = JSON.stringify(state);
        storage.setItem('state', serializedState);
    } catch (err) {
        // Ignore write errors.
    }
};

export const loadSessionState = createLoadStateFor(window.sessionStorage);
export const saveSessionState = createSaveStateFor(window.sessionStorage);

export const loadLocalState = createLoadStateFor(window.localStorage);
export const saveLocalState = createSaveStateFor(window.localStorage);