save-as-ebook/web-extension/background.js

chrome.runtime.onMessage.addListener(function(request, sender, sendResponse) {
    if (request.type === 'get') {
        chrome.storage.local.get('allPages', function (data) {
            if (!data || !data.allPages) {
                sendResponse({allPages: []});
            }
            sendResponse({allPages: data.allPages});
        })
    }
    if (request.type === 'set') {
        chrome.storage.local.set({'allPages': request.pages});
    }
    if (request.type === 'remove') {
        chrome.storage.local.remove('allPages');
        chrome.storage.local.remove('title');
    }
    if (request.type === 'get title') {
        chrome.storage.local.get('title', function (data) {
            if (!data || !data.title || data.title.trim().length === 0) {
                sendResponse({title: 'eBook'});
            } else {
                sendResponse({title: data.title});
            }
        })
    }
    if (request.type === 'set title') {
        chrome.storage.local.set({'title': request.title});
    }
    return true;
});