adding a no change return policy

1 files changed, 20 insertions, 11 deletions

diff --git a/pyaggr3g470r/views/views.py b/pyaggr3g470r/views/views.py
index 189fd53f..2aeaaa20 100644
--- a/pyaggr3g470r/views/views.py
+++ b/pyaggr3g470r/views/views.py
@@ -30,11 +30,11 @@ import os
 import string
 import random
 import hashlib
+import logging
 import datetime
-from collections import namedtuple
 from bootstrap import application as app, db
 from flask import render_template, request, flash, session, \
-                  url_for, redirect, g, current_app, make_response
+                  url_for, redirect, g, current_app, make_response, Response
 from flask.ext.login import LoginManager, login_user, logout_user, \
                             login_required, current_user, AnonymousUserMixin
 from flask.ext.principal import Principal, Identity, AnonymousIdentity, \
@@ -46,12 +46,13 @@ from sqlalchemy.exc import IntegrityError
 from werkzeug import generate_password_hash
 
 import conf
+from pyaggr3g470r.lib.utils import to_hash
 from pyaggr3g470r import utils, notifications, export
 from pyaggr3g470r.models import User, Feed, Article, Role
 from pyaggr3g470r.decorators import feed_access_required
-from pyaggr3g470r.forms import SignupForm, SigninForm, \
-                    ProfileForm, UserForm, RecoverPasswordForm, \
-                    AddFeedForm, InformationMessageForm
+from pyaggr3g470r.forms import SignupForm, SigninForm, InformationMessageForm,\
+                    ProfileForm, UserForm, RecoverPasswordForm \
+
 from pyaggr3g470r.controllers import UserController, FeedController, \
                                      ArticleController
 
@@ -62,6 +63,7 @@ admin_permission = Permission(RoleNeed('admin'))
 
 login_manager = LoginManager()
 login_manager.init_app(app)
+logger = logging.getLogger(__name__)
 
 #
 # Management of the user's session.
@@ -235,7 +237,6 @@ def render_home(filters=None, head_titles=None,
     arti_contr = ArticleController(g.user.id)
     feeds = {feed.id: feed.title for feed in feed_contr.read()}
 
-    unread = arti_contr.count_by_feed(readed=False)
     in_error = {feed.id: feed.error_count for feed in
                 feed_contr.read(error_count__gt=2)}
 
@@ -282,11 +283,19 @@ def render_home(filters=None, head_titles=None,
             and filter_ != 'all' and not articles:
         return redirect(gen_url(filter_='all'))
 
-    return render_template('home.html', page_to_render=page_to_render,
-                           gen_url=gen_url, feed_id=feed_id,
-                           filter_=filter_, limit=limit, feeds=feeds,
-                           unread=unread, articles=articles, in_error=in_error,
-                           head_titles=head_titles, sort_=sort_, **kwargs)
+    etag = to_hash("".join([str(filters[key]) for key in sorted(filters)])
+                   + "".join([str(art.id) for art in articles]))
+    if request.headers.get('if-none-match') == etag:
+        return Response(status=304, headers={'etag': etag,
+                        'Cache-Control': 'pragma: no-cache'})
+    response = make_response(render_template('home.html', gen_url=gen_url,
+                             feed_id=feed_id, page_to_render=page_to_render,
+                             filter_=filter_, limit=limit, feeds=feeds,
+                             unread=arti_contr.count_by_feed(readed=False),
+                             articles=articles, in_error=in_error,
+                             head_titles=head_titles, sort_=sort_, **kwargs))
+    response.headers['etag'] = etag
+    return response
 
 
 @app.route('/')