Chrome Extensions: Background Script Catch Network and HTTP Errors

Question

I\'m developing a small Chrome extension for personal use on a very specific case (website automation) but I\'ve a problem. How can I catch a network error on a background s

Answer 1

With help of the the user @Xan, I managed to come up with this:

function extractStatus(line) {
    var match = line.match(/[^ ]* (\d{3}) (.*)/);
    if (match)
        return {code: match[1], message: match[2]};
    else
        return undefined;
}   

chrome.tabs.query({active: true, lastFocusedWindow: true }, function(tabsArray) {
    tab = tabsArray[0];
    scope = {urls: ["https://example.com/*"], tabId: tab.id};
    console.log("Listening for errors...");

    // ::net errors
    chrome.webRequest.onErrorOccurred.addListener(handleNetworkError, scope);

    // HTTP errors
    chrome.webRequest.onHeadersReceived.addListener(function(details) {

        var status = extractStatus(details.statusLine);
        if (!status)
            return;

        if (status.code.charAt(0) == '5' || status.code.charAt(0) == '4')
            handleNetworkError();           

    }, scope);
});