browser: Allow more control of the referrer

weboob/browser/browsers.py

@@ -96,6 +96,11 @@ class Browser(object):
     Saved state variables.
     """
 
+    ALLOW_REFERRER = True
+    """
+    Controls the behavior of get_referrer.
+    """
+
     @classmethod
     def asset(cls, localfile):
         """
@@ -451,6 +456,11 @@ class Browser(object):
 
         Reference: https://en.wikipedia.org/wiki/HTTP_referer
 
+        The behavior can be controlled through the ALLOW_REFERRER attribute.
+        True always allows the referers
+        to be sent, False never, and None only if it is within
+        the same domain.
+
         :param oldurl: Current absolute URL
         :type oldurl: str or None
 
@@ -459,21 +469,21 @@ class Browser(object):
 
         :rtype: str or None
         """
+        if self.ALLOW_REFERRER is False:
+            return
         if oldurl is None:
-            return None
+            return
         old = urlparse(oldurl)
         new = urlparse(newurl)
         # Do not leak secure URLs to insecure URLs
         if old.scheme == 'https' and new.scheme != 'https':
-            return None
+            return
         # Reloading the page. Usually no referrer.
         if oldurl == newurl:
-            return None
-        # TODO maybe implement some *optional* privacy features:
-        # * do not leak referrer to other domains (often breaks websites)
-        # * send a fake referrer (root of the current domain)
-        # * never send the referrer
-        # Inspired by the RefControl Firefox addon.
+            return
+        # Domain-based privacy
+        if self.ALLOW_REFERRER is None and old.netloc != new.netloc:
+            return
         return oldurl
 
 

weboob/browser/profiles.py

@@ -80,6 +80,8 @@ class GoogleBot(Profile):
     """
     Try to mimic Googlebot.
     Keep in mind there are ways to authenticate real Googlebot IPs.
+
+    You will most likely want to set ALLOW_REFERRER to False.
     """
 
     def setup_session(self, session):