background.js

chrome.runtime.getPackageDirectoryEntry(function (root) {
    root.getFile("./data/list.json", {}, function (fileEntry) {
        fileEntry.file(function (file) {
            var reader = new FileReader();
            reader.onloadend = function (e) {
                let parsed = JSON.parse(this.result);
                chrome.webRequest.onBeforeRequest.addListener(
                    function (details) { return { cancel: true }; },
                    { urls: parsed.blockedSites },
                    ["blocking"]
                );
                chrome.browserAction.setBadgeText({ text: 'ON' });
                chrome.browserAction.setBadgeBackgroundColor({ color: '#4688F1' });
                chrome.browserAction.setTitle({ title: "Another Ad Block is Active." });
            };
            reader.readAsText(file);
        });
    });
})