backporting mergin_hook to support hook's requests in wheezy

weboob/tools/browser2/sessions.py

@@ -27,8 +27,79 @@ except ImportError:
 
 from requests import Session
 from requests.adapters import DEFAULT_POOLSIZE, HTTPAdapter
+from requests.compat import cookielib, OrderedDict
+from requests.cookies import cookiejar_from_dict, RequestsCookieJar
+from requests.models import PreparedRequest
+from requests.sessions import merge_setting
+from requests.structures import CaseInsensitiveDict
+from requests.utils import get_netrc_auth
 
-class FuturesSession(Session):
+def merge_hooks(request_hooks, session_hooks, dict_class=OrderedDict):
+    """
+    Properly merges both requests and session hooks.
+
+    This is necessary because when request_hooks == {'response': []}, the
+    merge breaks Session hooks entirely.
+
+    Backport from request so we can use it in wheezy
+    """
+    if session_hooks is None or session_hooks.get('response') == []:
+        return request_hooks
+
+    if request_hooks is None or request_hooks.get('response') == []:
+        return session_hooks
+
+    ret = {}
+    for (k, v) in request_hooks.items():
+        if v is not None:
+            ret[k] = set(v).union(session_hooks.get(k, []))
+
+    return ret
+
+
+class WeboobSession(Session):
+
+    def prepare_request(self, request):
+        """Constructs a :class:`PreparedRequest <PreparedRequest>` for
+        transmission and returns it. The :class:`PreparedRequest` has settings
+        merged from the :class:`Request <Request>` instance and those of the
+        :class:`Session`.
+
+        :param request: :class:`Request` instance to prepare with this
+        session's settings.
+        """
+        cookies = request.cookies or {}
+
+        # Bootstrap CookieJar.
+        if not isinstance(cookies, cookielib.CookieJar):
+            cookies = cookiejar_from_dict(cookies)
+
+        # Merge with session cookies
+        merged_cookies = RequestsCookieJar()
+        merged_cookies.update(self.cookies)
+        merged_cookies.update(cookies)
+
+
+        # Set environment's basic authentication if not explicitly set.
+        auth = request.auth
+        if self.trust_env and not auth and not self.auth:
+            auth = get_netrc_auth(request.url)
+
+        p = PreparedRequest()
+        p.prepare(
+            method=request.method.upper(),
+            url=request.url,
+            files=request.files,
+            data=request.data,
+            headers=merge_setting(request.headers, self.headers, dict_class=CaseInsensitiveDict),
+            params=merge_setting(request.params, self.params),
+            auth=merge_setting(auth, self.auth),
+            cookies=merged_cookies,
+            hooks=merge_hooks(request.hooks, self.hooks),
+        )
+        return p
+
+class FuturesSession(WeboobSession):
 
     def __init__(self, executor=None, max_workers=2, *args, **kwargs):
         """Creates a FuturesSession