Getting all cookies from WKWebView

aporat picture aporat · Oct 15, 2015 · Viewed 65.2k times · Source

while getting cookies from UIWebView seems straightforward by using NSHTTPCookieStorage.sharedHTTPCookieStorage(), it seems WKWebView stores the cookies somewhere else.

I did some research, and I was able to get some cookies from the grabbing it from NSHTTPURLResponse object. this, however, does not contain all the cookies used by WKWebView:

func webView(webView: WKWebView, decidePolicyForNavigationResponse navigationResponse: WKNavigationResponse, decisionHandler: (WKNavigationResponsePolicy) -> Void) {

  if let httpResponse = navigationResponse.response as? NSHTTPURLResponse {
    if let headers = httpResponse.allHeaderFields as? [String: String], url = httpResponse.URL {
      let cookies = NSHTTPCookie.cookiesWithResponseHeaderFields(headers, forURL: url)

      for cookie in cookies {
        logDebug(cookie.description)

        logDebug("found cookie " + cookie.name + " " + cookie.value)
      }
    }
  }
}

Strangely, there's also a class WKWebsiteDataStore in ios 9 that responsible for managing cookies in WKWebView, however, the class does not contain a public method to retrieve the cookies data:

let storage = WKWebsiteDataStore.defaultDataStore()

storage.fetchDataRecordsOfTypes([WKWebsiteDataTypeCookies], completionHandler: { (records) -> Void in
  for record in records {
    logDebug("cookie record is " + record.debugDescription)

    for dataType in record.dataTypes {
      logDebug("data type is " + dataType.debugDescription)

      // get cookie data??
    }
  }
})

Is there a workaround for getting the cookie data?

Answer

Stefan Arentz picture Stefan Arentz · Oct 18, 2015

Cookies used (created) by the WKWebView are actually correctly stored in the NSHTTPCookieStorage.sharedHTTPCookieStorage().

The problem is that the WKWebView does not write back the cookies immediately. I think it does this on its own schedule. For example when a WKWebView is closed or maybe periodically.

So eventually they do end up in there, but when is unpredictable.

You may be able to force a 'sync' to the shared NSHTTPCookieStorage by closing your WKWebView. Please let us know if this works.

Update: I just remembered that in Firefox for iOS we force the WKWebView to flush its internal data, including cookies, by replacing its WKProcessPool with a new one. There is no official API, but I am pretty sure that is the most reliable workaround right now.