Can we download a webpage completely with chrome.downloads.download? (Google Chrome Extension)

Question

I want to save a wabpage completely from my Google Chrome extension. I added "downloads", "<all_urls>" permissions and confirmed that the following code save the Google page to google.html .

  chrome.downloads.download(
            { url: "http://www.google.com",
              filename: "google.html" },
            function (x) { console.log(x); })

However, this code only saves the html file. Stylesheets, scripts and images are not be saved. I want to save the webpage completely, as if I save the page with the dialog, selecting Format: Webpage, Complete .

I looked into the document but I couldn't find a way.

So my question is: how can I download a webpage completely from an extension using the api(s) of Google Chrome?

Answer 1

The downloads API downloads a single resource only. If you want to save a complete web page, then you can first open the web page, then export it as MHTML using chrome.pageCapture.saveAsMHTML , create a blob: -URL for the exported Blob using URL.createObjectURL and finally save this URL using the chrome.downloads.download API.

The pageCapture API requires a valid tabId. For instance:

// Create new tab, wait until it is loaded and save the page
chrome.tabs.create({
    url: 'http://example.com'
}, function(tab) {
    chrome.tabs.onUpdated.addListener(function func(tabId, changeInfo) {
        if (tabId == tab.id && changeInfo.status == 'complete') {
            chrome.tabs.onUpdated.removeListener(func);
            savePage(tabId);
        }
    });
});

function savePage(tabId) {
    chrome.pageCapture.saveAsMHTML({
        tabId: tabId
    }, function(blob) {
        var url = URL.createObjectURL(blob);
        // Optional: chrome.tabs.remove(tabId); // to close the tab
        chrome.downloads.download({
            url: url,
            filename: 'whatever.mhtml'
        });
    });
}

To try out, put the previous code in background.js ,
add the permissions to manifest.json (as shown below) and reload the extension. Then example.com will be opened, and the web page will be saved as a self-contained MHTML file.

{
    "name": "Save full web page",
    "version": "1",
    "manifest_version": 2,
    "background": {
        "scripts": ["background.js"]
    },
    "permissions": [
        "pageCapture",
        "downloads"
    ]
}

Answer 2

不，它不会为你下载所有文件：images，js，css等你应该使用像HTTRACK这样的工具。