Last week I posted a kind of vague question as I was trying to join data from an external Rest API with a local SQLAlchemy schema. Unsurprisingly, I didn't get a lot of responses and after some experimentation with parsing the response json into a temporary table I've decided to move away from this approach and add a new resolver for the external API that can be called separately from the resolver for SQLAlchemy. This is what I have so far for the querying the external API:
class Red(graphene.ObjectType):
redName = graphene.String()
accessLevel = graphene.String()
numBytes = graphene.Int()
class Query(graphene.ObjectType):
red = graphene.Field(Red, redName = graphene.String(required=True))
def resolve_red(self, info, **kwargs):
dataset_Red = <custom library for querying API>.dataset(kwargs['redName'])
dataset_Red.get()
resp = dataset_Red.properties
return json.dumps(resp)
GraphiQL recognizes my new resolver and will run the query with no errors but it returns no data. For example, if this is my query:
query{red(redName:"<dataset_name>") {
accessLevel
numBytes
}
}
I get the following response:
{
"data": {
"red": {
"accessLevel": null,
"numBytes": null
}
}
}
What did I miss? I'm thinking there's an issue with class definition. Can someone show me what I did wrong?
I think you should return Red type from resolver resolve_red instead of json dumped string:
class Red(graphene.ObjectType):
redName = graphene.String()
accessLevel = graphene.String()
numBytes = graphene.Int()
class Query(graphene.ObjectType):
red = graphene.Field(Red, redName = graphene.String(required=True))
def resolve_red(self, info, **kwargs):
dataset_Red = <custom library for querying API>.dataset(kwargs['redName'])
dataset_Red.get()
resp = dataset_Red.properties
return Red(
redName=resp.get('redName'),
accessLevel=resp.get('accessLevel'),
NumBytes=resp.get('numBytes')
)
Or assuming fields in response are the same as Red attributes:
class Red(graphene.ObjectType):
redName = graphene.String()
accessLevel = graphene.String()
numBytes = graphene.Int()
class Query(graphene.ObjectType):
red = graphene.Field(Red, redName = graphene.String(required=True))
def resolve_red(self, info, **kwargs):
dataset_Red = <custom library for querying API>.dataset(kwargs['redName'])
dataset_Red.get()
resp = dataset_Red.properties
return Red(**resp)
Sound I found a solution that seems to work. The issue was the response type, I had to serialize and then deserialize it for flask (obvious right?).
I added this two functions:
def _json_object_hook(d):
return namedtuple('X', d.keys())(*d.values())
def json2obj(data):
return json.loads(data, object_hook=_json_object_hook)
And then changed my resolver to call json2obj on the response:
def resolve_red(self, info, **kwargs):
dataset_Red = <custom library for querying API>.dataset(kwargs['redName'])
dataset_Red.get()
resp = dataset_Red.properties
return json2obj(json.dumps(resp))
I found this solution in another stackoverflow post but now I can't find the original. If anyone else finds it, please add a link in the comments and I'll add it to this answer.
I have to create API endpoint that will take data from GET request body. It will find necessary data in already created database to perform calculation and then it should return calculation result as response.
So I found a way to do it but I'm not sure if it should look like this. It works but you know :)
urls.py
schema_view = get_schema_view(
openapi.Info(
title="API Test",
default_version='0.0.1',
description="Test",
),
public=True,
)
urlpatterns = [
path('docs/', schema_view.with_ui('redoc', cache_timeout=0), name='schema-redoc'),
path('equation/1/example', EquationView.as_view()),
#... more paths to other equations...
]
view.py
def get_emission_val(req_emiss_fac):
try:
return Emission.objects.get(emission_factor=req_emiss_fac)
except Emission.DoesNotExist:
raise Http404("Emission value does not exist in database")
equation_response = openapi.Response('response description', EquationResponseSerializer)
#swagger_auto_schema(
query_serializer=EquationRequestSerializer,
responses={
'404':'Emission factor does not exist in database',
'200': equation_response
},
)
class EquationView(APIView):
def get(self, request):
emission_val = get_emission_val(request.data['emission_factor'])
combusted_val = request.data['combusted_value']
emissions = combusted_val * emission_val.co2_emission
return Response({'emissions':emissions})
serializers.py
class EquationRequestSerializer(serializers.Serializer):
emission_factor = serializers.CharField()
combusted_value = serializers.FloatField()
class EquationResponseSerializer(serializers.Serializer):
emission = serializers.FloatField()
What do you think about this approach? I'm not sure if I have to do it in this way. I'm using swagger and additional serializers for gerenerating api docs
Example get request body:
{
"emission_factor":"Test",
"combusted_value":1.0
}
Example response:
{
"emissions": 1.5129
}
class ForgotidAPI(generics.GenericAPIView):
serializer_class = ForgotidSerualizer
def post(self, request, *args, **kwargs):
Email = request.data.getlist('email')
First_name = request.data.getlist('first_name')
test = User.objects.get(email=Email)
print('e-mail : ', Email);
print('your name' : , First_name);
print('test : ', test)
return Response(
{
"email": "test",
"first_name": "test",
}
)
I would like to compare the saved emails to the emails I sent and print the user accordingly.
Only the statement'test = User.objects.get (email = Email)' is not executed. How do you run it?
Okay, the problem is strange and it was solved by using filter() in place of get(). So:
test = User.objects.filter(email=Email)
#handsomecode Don't use capitalize letter as variable as you did for Email = request.data.getlist('email') it's a bad practice, define variables with lowercase letters.
I'm using WTForms (together with Flask, flask-wtf, sqlalchemy) to validate incoming JSON for REST APIs. I realize that WTForms is aimed more towards HTML form rendering and validation, but I chose it because it can autogenerate forms out of my sqlalchemy models (thanks to wtforms.ext.sqlalchemy).
Anyway, here is the problem. One of my models includes boolean field which translates to wtforms.BooleanField with DataRequired validator. The issue is that validation fails with 'This field is required' error message even if I pass correct data. My Form:
class MyForm(Form):
name = TextField('name', validators=[DataRequired()])
disabled = BooleanField('disabled', validators=[DataRequired()])
JSON data is like this:
'{"name": "John", "disabled": "false"}'
What I'm expecting:
{"disabled": "false"} -> validates successful, coerced Python data: {'disabled': False}
{"disabled": "true"} -> validates successful, coerced Python data: {'disabled': True}
{"disabled": ""} or '{"disabled": "foo"}' -> fails validation
Currently in first case validation is failed with {'disabled': [u'This field is required.']}
I know there is a note in docs that says DataRequired validator "require coerced data, not input data", but 1) the form is autogenerated by wtforms.ext.sqlalchemy and 2) how it is supposed to behave if I use InputRequired validator? Check (via form.validate()) that some data exists and then check that this data is "true" or "false"?
To summarize, my question is:
What is the correct way of validating wtforms.BooleanField?
Maybe there is some other framework that can validate incoming JSON against given sqlalchemy models?
Thanks.
There are a number of ways of going about this. You could write your own converter to make of use a radiofield with true/false choices, you could use a data filter, you could set a default value, but I think the behavior you want will be possible with this:
MyForm = model_form(MyModel, db_session=db, field_args = {
'disabled' : {
'false_values': ['false'],
'validators' : [InputRequired()] }
})
EDIT: If you wanted a stricter handler you could do the following:
class BooleanRequired(object):
field_flags = ('required', )
def __init__(self, message=None):
self.message = message
def __call__(self, form, field):
if field.data is None:
if self.message is None:
message = field.gettext('This field is required.')
else:
message = self.message
field.errors[:] = []
raise StopValidation(message)
class StrictBooleanField(BooleanField):
def process_formdata(self, valuelist):
self.data = None
if valuelist:
if valuelist[0] == 'false':
self.data = False
elif valuelist[0] == 'true':
self.data = True
class StrictModelConverter(ModelConverter):
#converts('Boolean')
def conv_Boolean(self, field_args, **extra):
return StrictBooleanField(**field_args)
MyForm = model_form(MyModel, db_session=db, converter=StrictModelConverter(),
field_args = { 'disabled' : { 'validators': [BooleanRequired()] }
})
I could reproduce my bug using servside OAuth2.0 only so it's not javascript and the issue is that I must reload to make login / logout take effect and I want it to work without javascript. I have an idea that making logout twice makes logout effective so I could use a custom request handler for /login and/or /logour or just /sessionchange that will do a self.redirect but it's not the clean solution. Maybe you can take a look at the code and see why I must logout twice ie I must reload and can I workaround this using a self.redirect ? Am I using cookies the right way, the new cookie, or do I get it mixed up? I'm doing this both for the website and for the FB app. I'll be glad if you can come with any suggestion. There's a background of 2 related questions from before I removed the Javascript. And BTW should I use class Facebook or facebook.py? I think I commented out where the old cookie is set and that this will be correct once OAuth 2.0 handles my authentication serverside. Can you comment or answer? Thank you in advance if you can review and comment.
How to make my welcome text appear?
How to make this page reload on login / logout?
Why my strange results rendering the user object?
login.html
{% load i18n %}
<?xml version="1.0" encoding="utf-8"?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head> <title>{% trans "Log in" %}</title>
<script type="text/javascript">
var _gaq = _gaq || [];
_gaq.push(['_setAccount', '{{analytics}}']);
_gaq.push(['_trackPageview']);
(function() {
var ga = document.createElement('script'); ga.type = 'text/javascript'; ga.async = true;
ga.src = ('https:' == document.location.protocol ? 'https://ssl' : 'http://www') + '.google-analytics.com/ga.js';
var s = document.getElementsByTagName('script')[0]; s.parentNode.insertBefore(ga, s);
})();
</script>
</head>
<body>
<div id="fb-root"></div>
<script>
window.fbAsyncInit = function() {
FB.init({
appId : '164355773607006', // App ID
channelURL : '//WWW.KOOLBUSINESS.COM/static/channel.html', // Channel File
status : true, // check login status
cookie : true, // enable cookies to allow the server to access the session
oauth : true, // enable OAuth 2.0
xfbml : true // parse XFBML
});
// Additional initialization code here
};
// Load the SDK Asynchronously
(function(d){
var js, id = 'facebook-jssdk'; if (d.getElementById(id)) {return;}
js = d.createElement('script'); js.id = id; js.async = true;
js.src = "//connect.facebook.net/en_US/all.js";
d.getElementsByTagName('head')[0].appendChild(js);
}(document));
</script>
<img src="/_/img/loginwithfacebook.png">
<img src="/_/img/loginwithgoogle.png"><br>{% if user %}Logout Google{% endif %}
{% if current_user %}Logout Facebook {% endif %}
{% if current_user %}Logout Facebook JS {% endif %}
</body>
</html>
class BaseHandler(webapp.RequestHandler):
facebook = None
user = None
csrf_protect = True
#property
def current_user(self):
if not hasattr(self, "_current_user"):
self._current_user = None
cookie = facebook.get_user_from_cookie(
self.request.cookies, facebookconf.FACEBOOK_APP_ID, facebookconf.FACEBOOK_APP_SECRET)
logging.debug("logging cookie"+str(cookie))
if cookie:
# Store a local instance of the user data so we don't need
# a round-trip to Facebook on every request
user = FBUser.get_by_key_name(cookie["uid"])
logging.debug("user "+str(user))
logging.debug("username "+str(user.name))
if not user:
graph = facebook.GraphAPI(cookie["access_token"])
profile = graph.get_object("me")
user = FBUser(key_name=str(profile["id"]),
id=str(profile["id"]),
name=profile["name"],
profile_url=profile["link"],
access_token=cookie["access_token"])
user.put()
elif user.access_token != cookie["access_token"]:
user.access_token = cookie["access_token"]
user.put()
self._current_user = user
return self._current_user
def initialize(self, request, response):
"""General initialization for every request"""
super(BaseHandler, self).initialize(request, response)
try:
self.init_facebook()
self.init_csrf()
self.response.headers[u'P3P'] = u'CP=HONK' # iframe cookies in IE
except Exception, ex:
self.log_exception(ex)
raise
def handle_exception(self, ex, debug_mode):
"""Invoked for unhandled exceptions by webapp"""
self.log_exception(ex)
self.render(u'error',
trace=traceback.format_exc(), debug_mode=debug_mode)
def log_exception(self, ex):
"""Internal logging handler to reduce some App Engine noise in errors"""
msg = ((str(ex) or ex.__class__.__name__) +
u': \n' + traceback.format_exc())
if isinstance(ex, urlfetch.DownloadError) or \
isinstance(ex, DeadlineExceededError) or \
isinstance(ex, CsrfException) or \
isinstance(ex, taskqueue.TransientError):
logging.warn(msg)
else:
logging.error(msg)
def set_cookie(self, name, value, expires=None):
if value is None:
value = 'deleted'
expires = datetime.timedelta(minutes=-50000)
jar = Cookie.SimpleCookie()
jar[name] = value
jar[name]['path'] = u'/'
if expires:
if isinstance(expires, datetime.timedelta):
expires = datetime.datetime.now() + expires
if isinstance(expires, datetime.datetime):
expires = expires.strftime('%a, %d %b %Y %H:%M:%S')
jar[name]['expires'] = expires
self.response.headers.add_header(*jar.output().split(u': ', 1))
def render(self, name, **data):
"""Render a template"""
if not data:
data = {}
data[u'js_conf'] = json.dumps({
u'appId': facebookconf.FACEBOOK_APP_ID,
u'canvasName': facebookconf.FACEBOOK_CANVAS_NAME,
u'userIdOnServer': self.user.id if self.user else None,
})
data[u'logged_in_user'] = self.user
data[u'message'] = self.get_message()
data[u'csrf_token'] = self.csrf_token
data[u'canvas_name'] = facebookconf.FACEBOOK_CANVAS_NAME
data[u'current_user']=self.current_user
data[u'user']=users.get_current_user()
data[u'facebook_app_id']=facebookconf.FACEBOOK_APP_ID
user = users.get_current_user()
data[u'logout_url']=users.create_logout_url(self.request.uri) if users.get_current_user() else 'https://www.facebook.com/dialog/oauth?client_id=164355773607006&redirect_uri='+self.request.uri
host=os.environ.get('HTTP_HOST', os.environ['SERVER_NAME'])
data[u'host']=host
if host.find('.br') > 0:
logo = 'Montao.com.br'
logo_url = '/_/img/montao_small.gif'
analytics = 'UA-637933-12'
domain = None
else:
logo = 'Koolbusiness.com'
logo_url = '/_/img/kool_business.png'
analytics = 'UA-3492973-18'
domain = 'koolbusiness'
data[u'domain']=domain
data[u'analytics']=analytics
data[u'logo']=logo
data[u'logo_url']=logo_url
data[u'admin']=users.is_current_user_admin()
if user:
data[u'greeting'] = ("Welcome, %s! (sign out)" %
(user.nickname(), users.create_logout_url("/")))
self.response.out.write(template.render(
os.path.join(
os.path.dirname(__file__), 'templates', name + '.html'),
data))
def init_facebook(self):
facebook = Facebook()
user = None
# initial facebook request comes in as a POST with a signed_request
if u'signed_request' in self.request.POST:
facebook.load_signed_request(self.request.get('signed_request'))
# we reset the method to GET because a request from facebook with a
# signed_request uses POST for security reasons, despite it
# actually being a GET. in webapp causes loss of request.POST data.
self.request.method = u'GET'
#self.set_cookie(
#'u', facebook.user_cookie, datetime.timedelta(minutes=1440))
elif 'u' in self.request.cookies:
facebook.load_signed_request(self.request.cookies.get('u'))
# try to load or create a user object
if facebook.user_id:
user = FBUser.get_by_key_name(facebook.user_id)
if user:
# update stored access_token
if facebook.access_token and \
facebook.access_token != user.access_token:
user.access_token = facebook.access_token
user.put()
# refresh data if we failed in doing so after a realtime ping
if user.dirty:
user.refresh_data()
# restore stored access_token if necessary
if not facebook.access_token:
facebook.access_token = user.access_token
if not user and facebook.access_token:
me = facebook.api(u'/me', {u'fields': _USER_FIELDS})
try:
friends = [user[u'id'] for user in me[u'friends'][u'data']]
user = FBUser(key_name=facebook.user_id,
id=facebook.user_id, friends=friends,
access_token=facebook.access_token, name=me[u'name'],
email=me.get(u'email'), picture=me[u'picture'])
user.put()
except KeyError, ex:
pass # ignore if can't get the minimum fields
self.facebook = facebook
self.user = user
def init_csrf(self):
"""Issue and handle CSRF token as necessary"""
self.csrf_token = self.request.cookies.get(u'c')
if not self.csrf_token:
self.csrf_token = str(uuid4())[:8]
self.set_cookie('c', self.csrf_token)
if self.request.method == u'POST' and self.csrf_protect and \
self.csrf_token != self.request.POST.get(u'_csrf_token'):
raise CsrfException(u'Missing or invalid CSRF token.')
def set_message(self, **obj):
"""Simple message support"""
self.set_cookie('m', base64.b64encode(json.dumps(obj)) if obj else None)
def get_message(self):
"""Get and clear the current message"""
message = self.request.cookies.get(u'm')
if message:
self.set_message() # clear the current cookie
return json.loads(base64.b64decode(message))
class Facebook(object):
"""Wraps the Facebook specific logic"""
def __init__(self, app_id=facebookconf.FACEBOOK_APP_ID,
app_secret=facebookconf.FACEBOOK_APP_SECRET):
self.app_id = app_id
self.app_secret = app_secret
self.user_id = None
self.access_token = None
self.signed_request = {}
def api(self, path, params=None, method=u'GET', domain=u'graph'):
"""Make API calls"""
if not params:
params = {}
params[u'method'] = method
if u'access_token' not in params and self.access_token:
params[u'access_token'] = self.access_token
result = json.loads(urlfetch.fetch(
url=u'https://' + domain + u'.facebook.com' + path,
payload=urllib.urlencode(params),
method=urlfetch.POST,
headers={
u'Content-Type': u'application/x-www-form-urlencoded'})
.content)
if isinstance(result, dict) and u'error' in result:
raise FacebookApiError(result)
return result
def load_signed_request(self, signed_request):
"""Load the user state from a signed_request value"""
try:
sig, payload = signed_request.split(u'.', 1)
sig = self.base64_url_decode(sig)
data = json.loads(self.base64_url_decode(payload))
expected_sig = hmac.new(
self.app_secret, msg=payload, digestmod=hashlib.sha256).digest()
# allow the signed_request to function for upto 1 day
if sig == expected_sig and \
data[u'issued_at'] > (time.time() - 86400):
self.signed_request = data
self.user_id = data.get(u'user_id')
self.access_token = data.get(u'oauth_token')
except ValueError, ex:
pass # ignore if can't split on dot
#property
def user_cookie(self):
"""Generate a signed_request value based on current state"""
if not self.user_id:
return
payload = self.base64_url_encode(json.dumps({
u'user_id': self.user_id,
u'issued_at': str(int(time.time())),
}))
sig = self.base64_url_encode(hmac.new(
self.app_secret, msg=payload, digestmod=hashlib.sha256).digest())
return sig + '.' + payload
#staticmethod
def base64_url_decode(data):
data = data.encode(u'ascii')
data += '=' * (4 - (len(data) % 4))
return base64.urlsafe_b64decode(data)
#staticmethod
def base64_url_encode(data):
return base64.urlsafe_b64encode(data).rstrip('=')
facebook.py
#!/usr/bin/env python
#
# Copyright 2010 Facebook
#
# Licensed under the Apache License, Version 2.0 (the "License"); you may
# not use this file except in compliance with the License. You may obtain
# a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
# License for the specific language governing permissions and limitations
# under the License.
"""Python client library for the Facebook Platform.
This client library is designed to support the Graph API and the official
Facebook JavaScript SDK, which is the canonical way to implement
Facebook authentication. Read more about the Graph API at
http://developers.facebook.com/docs/api. You can download the Facebook
JavaScript SDK at http://github.com/facebook/connect-js/.
If your application is using Google AppEngine's webapp framework, your
usage of this module might look like this:
user = facebook.get_user_from_cookie(self.request.cookies, key, secret)
if user:
graph = facebook.GraphAPI(user["access_token"])
profile = graph.get_object("me")
friends = graph.get_connections("me", "friends")
"""
from google.appengine.dist import use_library
use_library('django', '1.2')
import cgi
import hashlib
import time
import urllib
#from django.utils import translation, simplejson as json
# Find a JSON parser
try:
# For Google AppEngine
from django.utils import simplejson
_parse_json = lambda s: simplejson.loads(s)
except ImportError:
try:
import simplejson
_parse_json = lambda s: simplejson.loads(s)
except ImportError:
import json
_parse_json = lambda s: json.loads(s)
class GraphAPI(object):
"""A client for the Facebook Graph API.
See http://developers.facebook.com/docs/api for complete documentation
for the API.
The Graph API is made up of the objects in Facebook (e.g., people, pages,
events, photos) and the connections between them (e.g., friends,
photo tags, and event RSVPs). This client provides access to those
primitive types in a generic way. For example, given an OAuth access
token, this will fetch the profile of the active user and the list
of the user's friends:
graph = facebook.GraphAPI(access_token)
user = graph.get_object("me")
friends = graph.get_connections(user["id"], "friends")
You can see a list of all of the objects and connections supported
by the API at http://developers.facebook.com/docs/reference/api/.
You can obtain an access token via OAuth or by using the Facebook
JavaScript SDK. See http://developers.facebook.com/docs/authentication/
for details.
If you are using the JavaScript SDK, you can use the
get_user_from_cookie() method below to get the OAuth access token
for the active user from the cookie saved by the SDK.
"""
def __init__(self, access_token=None):
self.access_token = access_token
def get_object(self, id, **args):
"""Fetchs the given object from the graph."""
return self.request(id, args)
def get_objects(self, ids, **args):
"""Fetchs all of the given object from the graph.
We return a map from ID to object. If any of the IDs are invalid,
we raise an exception.
"""
args["ids"] = ",".join(ids)
return self.request("", args)
def get_connections(self, id, connection_name, **args):
"""Fetchs the connections for given object."""
return self.request(id + "/" + connection_name, args)
def put_object(self, parent_object, connection_name, **data):
"""Writes the given object to the graph, connected to the given parent.
For example,
graph.put_object("me", "feed", message="Hello, world")
writes "Hello, world" to the active user's wall. Likewise, this
will comment on a the first post of the active user's feed:
feed = graph.get_connections("me", "feed")
post = feed["data"][0]
graph.put_object(post["id"], "comments", message="First!")
See http://developers.facebook.com/docs/api#publishing for all of
the supported writeable objects.
Most write operations require extended permissions. For example,
publishing wall posts requires the "publish_stream" permission. See
http://developers.facebook.com/docs/authentication/ for details about
extended permissions.
"""
assert self.access_token, "Write operations require an access token"
return self.request(parent_object + "/" + connection_name, post_args=data)
def put_wall_post(self, message, attachment={}, profile_id="me"):
"""Writes a wall post to the given profile's wall.
We default to writing to the authenticated user's wall if no
profile_id is specified.
attachment adds a structured attachment to the status message being
posted to the Wall. It should be a dictionary of the form:
{"name": "Link name"
"link": "http://www.example.com/",
"caption": "{*actor*} posted a new review",
"description": "This is a longer description of the attachment",
"picture": "http://www.example.com/thumbnail.jpg"}
"""
return self.put_object(profile_id, "feed", message=message, **attachment)
def put_comment(self, object_id, message):
"""Writes the given comment on the given post."""
return self.put_object(object_id, "comments", message=message)
def put_like(self, object_id):
"""Likes the given post."""
return self.put_object(object_id, "likes")
def delete_object(self, id):
"""Deletes the object with the given ID from the graph."""
self.request(id, post_args={"method": "delete"})
def request(self, path, args=None, post_args=None):
"""Fetches the given path in the Graph API.
We translate args to a valid query string. If post_args is given,
we send a POST request to the given path with the given arguments.
"""
if not args: args = {}
if self.access_token:
if post_args is not None:
post_args["access_token"] = self.access_token
else:
args["access_token"] = self.access_token
post_data = None if post_args is None else urllib.urlencode(post_args)
file = urllib.urlopen("https://graph.facebook.com/" + path + "?" +
urllib.urlencode(args), post_data)
try:
response = _parse_json(file.read())
finally:
file.close()
if response.get("error"):
raise GraphAPIError(response["error"]["type"],
response["error"]["message"])
return response
class GraphAPIError(Exception):
def __init__(self, type, message):
Exception.__init__(self, message)
self.type = type
##### NEXT TWO FUNCTIONS PULLED FROM https://github.com/jgorset/facepy/blob/master/facepy/signed_request.py
import base64
import hmac
def urlsafe_b64decode(str):
"""Perform Base 64 decoding for strings with missing padding."""
l = len(str)
pl = l % 4
return base64.urlsafe_b64decode(str.ljust(l+pl, "="))
def parse_signed_request(signed_request, secret):
"""
Parse signed_request given by Facebook (usually via POST),
decrypt with app secret.
Arguments:
signed_request -- Facebook's signed request given through POST
secret -- Application's app_secret required to decrpyt signed_request
"""
if "." in signed_request:
esig, payload = signed_request.split(".")
else:
return {}
sig = urlsafe_b64decode(str(esig))
data = _parse_json(urlsafe_b64decode(str(payload)))
if not isinstance(data, dict):
raise SignedRequestError("Pyload is not a json string!")
return {}
if data["algorithm"].upper() == "HMAC-SHA256":
if hmac.new(secret, payload, hashlib.sha256).digest() == sig:
return data
else:
raise SignedRequestError("Not HMAC-SHA256 encrypted!")
return {}
def get_user_from_cookie(cookies, app_id, app_secret):
"""Parses the cookie set by the official Facebook JavaScript SDK.
cookies should be a dictionary-like object mapping cookie names to
cookie values.
If the user is logged in via Facebook, we return a dictionary with the
keys "uid" and "access_token". The former is the user's Facebook ID,
and the latter can be used to make authenticated requests to the Graph API.
If the user is not logged in, we return None.
Download the official Facebook JavaScript SDK at
http://github.com/facebook/connect-js/. Read more about Facebook
authentication at http://developers.facebook.com/docs/authentication/.
"""
cookie = cookies.get("fbsr_" + app_id, "")
if not cookie:
return None
response = parse_signed_request(cookie, app_secret)
if not response:
return None
args = dict(
code = response['code'],
client_id = app_id,
client_secret = app_secret,
redirect_uri = '',
)
file = urllib.urlopen("https://graph.facebook.com/oauth/access_token?" + urllib.urlencode(args))
try:
token_response = file.read()
finally:
file.close()
access_token = cgi.parse_qs(token_response)["access_token"][-1]
return dict(
uid = response["user_id"],
access_token = access_token,
)
Some log traces are
2011-10-18 18:25:07.912
logging cookie{'access_token': 'AAACVewZBArF4BACUDwnDap5OrQQ5dx0sHEKuPJkIJJ8GdXlYdni5K50xKw6s8BSIDZCpKBtVWF9maHMoJeF9ZCRRYM1zgZD', 'uid': u'32740016'}
D 2011-10-18 18:25:07.925
user <__main__.FBUser object at 0x39d606ae980b528>
D 2011-10-18 18:25:07.925
username Niklas R
Now looking at the code that does this it seems to me that I'm confusing the module facebook with the variable facebook where one is the class facebook from the example project and one is the new recommended module facebook.py:
class BaseHandler(webapp.RequestHandler):
facebook = None
user = None
csrf_protect = True
#property
def current_user(self):
if not hasattr(self, "_current_user"):
self._current_user = None
cookie = facebook.get_user_from_cookie(
self.request.cookies, facebookconf.FACEBOOK_APP_ID, facebookconf.FACEBOOK_APP_SECRET)
logging.debug("logging cookie"+str(cookie))
if cookie:
# Store a local instance of the user data so we don't need
# a round-trip to Facebook on every request
user = FBUser.get_by_key_name(cookie["uid"])
logging.debug("user "+str(user))
logging.debug("username "+str(user.name))
if not user:
graph = facebook.GraphAPI(cookie["access_token"])
profile = graph.get_object("me")
user = FBUser(key_name=str(profile["id"]),
id=str(profile["id"]),
name=profile["name"],
profile_url=profile["link"],
access_token=cookie["access_token"])
user.put()
elif user.access_token != cookie["access_token"]:
user.access_token = cookie["access_token"]
user.put()
self._current_user = user
return self._current_user
How to add Facebook as OAuth 2.0 provider: Here's how I make "Login with facebook" for my website with OAuth instead of javascript / cookie this is python only for OAuth 2.0 with Facebook and as far as I can tell it's working:
class FBUser(db.Model):
id = db.StringProperty(required=True)
created = db.DateTimeProperty(auto_now_add=True)
updated = db.DateTimeProperty(auto_now=True)
name = db.StringProperty(required=True)
profile_url = db.StringProperty()
access_token = db.StringProperty(required=True)
name = db.StringProperty(required=True)
picture = db.StringProperty()
email = db.StringProperty()
friends = db.StringListProperty()
class I18NPage(I18NHandler):
def get(self):
if self.request.get('code'):
args = dict(
code = self.request.get('code'),
client_id = facebookconf.FACEBOOK_APP_ID,
client_secret = facebookconf.FACEBOOK_APP_SECRET,
redirect_uri = 'http://www.koolbusiness.com/',
)
logging.debug("client_id"+str(args))
file = urllib.urlopen("https://graph.facebook.com/oauth/access_token?" + urllib.urlencode(args))
try:
logging.debug("reading file")
token_response = file.read()
logging.debug("read file"+str(token_response))
finally:
file.close()
access_token = cgi.parse_qs(token_response)["access_token"][-1]
graph = main.GraphAPI(access_token)
user = graph.get_object("me") #write the access_token to the datastore
fbuser = main.FBUser.get_by_key_name(user["id"])
logging.debug("fbuser "+str(fbuser))
if not fbuser:
fbuser = main.FBUser(key_name=str(user["id"]),
id=str(user["id"]),
name=user["name"],
profile_url=user["link"],
access_token=access_token)
fbuser.put()
elif fbuser.access_token != access_token:
fbuser.access_token = access_token
fbuser.put()
The login link is
<img src="/_/img/loginwithfacebook.png"> that redirects and allows me to pick up the access_token in the method above and logout is straightforward:
{% trans "Log out" %}