ported to python 3 with backward compatibility

Procfile

@@ -1 +1 @@
-web: python exampleapp.py
+web: gunicorn exampleapp:app

exampleapp.py

@@ -3,7 +3,12 @@
 import base64
 import os
 import os.path
-import urllib
+try:
+    from urllib.parse import urlencode
+    from urllib.parse import parse_qs
+except ImportError:
+    from urllib import urlencode
+    from urlparse import parse_qs
 import hmac
 import json
 import hashlib
@@ -16,7 +21,7 @@
 requests = requests.session()
 
 app_url = 'https://graph.facebook.com/{0}'.format(FB_APP_ID)
-FB_APP_NAME = json.loads(requests.get(app_url).content).get('name')
+FB_APP_NAME = json.loads(requests.get(app_url).text).get('name')
 FB_APP_SECRET = os.environ.get('FACEBOOK_SECRET')
 
 
@@ -31,32 +36,32 @@ def oauth_login_url(preserve_path=True, next_url=None):
 
 
 def simple_dict_serialisation(params):
-    return "&".join(map(lambda k: "%s=%s" % (k, params[k]), params.keys()))
+    return "&".join(["%s=%s" % (k, params[k]) for k in list(params.keys())])
 
 
 def base64_url_encode(data):
     return base64.urlsafe_b64encode(data).rstrip('=')
 
 
 def fbapi_get_string(path,
-    domain=u'graph', params=None, access_token=None,
-    encode_func=urllib.urlencode):
+    domain='graph', params=None, access_token=None,
+    encode_func=urlencode):
     """Make an API call"""
 
     if not params:
         params = {}
-    params[u'method'] = u'GET'
+    params['method'] = 'GET'
     if access_token:
-        params[u'access_token'] = access_token
+        params['access_token'] = access_token
 
-    for k, v in params.iteritems():
+    for k, v in params.items():
         if hasattr(v, 'encode'):
             params[k] = v.encode('utf-8')
 
-    url = u'https://' + domain + u'.facebook.com' + path
+    url = 'https://' + domain + '.facebook.com' + path
     params_encoded = encode_func(params)
     url = url + params_encoded
-    result = requests.get(url).content
+    result = requests.get(url).text
 
     return result
 
@@ -67,7 +72,7 @@ def fbapi_auth(code):
               'client_secret': app.config['FB_APP_SECRET'],
               'code': code}
 
-    result = fbapi_get_string(path=u"/oauth/access_token?", params=params,
+    result = fbapi_get_string(path="/oauth/access_token?", params=params,
                               encode_func=simple_dict_serialisation)
     pairs = result.split("&", 1)
     result_dict = {}
@@ -79,14 +84,14 @@ def fbapi_auth(code):
 
 def fbapi_get_application_access_token(id):
     token = fbapi_get_string(
-        path=u"/oauth/access_token",
-        params=dict(grant_type=u'client_credentials', client_id=id,
+        path="/oauth/access_token",
+        params=dict(grant_type='client_credentials', client_id=id,
                     client_secret=app.config['FB_APP_SECRET']),
-        domain=u'graph')
+        domain='graph')
 
     token = token.split('=')[-1]
     if not str(id) in token:
-        print 'Token mismatch: %s not in %s' % (id, token)
+        print('Token mismatch: %s not in %s' % (id, token))
     return token
 
 
@@ -99,13 +104,13 @@ def fql(fql, token, args=None):
     url = "https://api.facebook.com/method/fql.query"
 
     r = requests.get(url, params=args)
-    return json.loads(r.content)
+    return json.loads(r.text)
 
 
 def fb_call(call, args=None):
     url = "https://graph.facebook.com/{0}".format(call)
     r = requests.get(url, params=args)
-    return json.loads(r.content)
+    return json.loads(r.text)
 
 
 
@@ -132,14 +137,14 @@ def get_token():
 
         sig = encoded_data[0]
         data = json.loads(urlsafe_b64decode(str(encoded_data[1]) +
-            (64-len(encoded_data[1])%64)*"="))
+            (64-len(encoded_data[1])%64)*"=").decode("utf-8"))
 
         if not data['algorithm'].upper() == 'HMAC-SHA256':
             raise ValueError('unknown algorithm {0}'.format(data['algorithm']))
 
-        h = hmac.new(FB_APP_SECRET, digestmod=hashlib.sha256)
-        h.update(encoded_data[1])
-        expected_sig = urlsafe_b64encode(h.digest()).replace('=', '')
+        h = hmac.new(FB_APP_SECRET.encode('utf-8'), digestmod=hashlib.sha256)
+        h.update(encoded_data[1].encode("utf-8"))
+        expected_sig = urlsafe_b64encode(h.digest()).decode("utf-8").replace('=', '')
 
         if sig != expected_sig:
             raise ValueError('bad signature')
@@ -153,9 +158,8 @@ def get_token():
             'code': data['code']
         }
 
-        from urlparse import parse_qs
         r = requests.get('https://graph.facebook.com/oauth/access_token', params=params)
-        token = parse_qs(r.content).get('access_token')
+        token = parse_qs(r.text).get('access_token')
 
         return token
 
@@ -218,4 +222,4 @@ def close():
     if app.config.get('FB_APP_ID') and app.config.get('FB_APP_SECRET'):
         app.run(host='0.0.0.0', port=port)
     else:
-        print 'Cannot start application without Facebook App Id and Secret set'
+        print('Cannot start application without Facebook App Id and Secret set')

requirements.txt

@@ -1,6 +1,8 @@
-Flask==0.7.2
-Jinja2==2.6
-Werkzeug==0.7.1
-simplejson==2.2.1
-wsgiref==0.1.2
-requests==0.10.4
+Flask==0.10.1
+Jinja2==2.7.1
+MarkupSafe==0.18
+Werkzeug==0.9.4
+gunicorn==18.0
+itsdangerous==0.23
+requests==2.0.1
+simplejson==3.3.1

runtime.txt

@@ -0,0 +1 @@
+python-3.3.2