I use omniauth for Facebook Authentification in my app. All works great. Now I try to implement a callback to a dynamic page which is the ID of an article.
The URL follows the pattern myapp.com/ads/:id/
On this page I use the auth gateway to /auth/facebook
The callback should come back exactly to this page (e.g. /ads/4711/).
I tried to accomplish this in routes:
match "/auth/facebook/callback" => "/ads/:id/"
which is obv not valid.
Also tried to work out this solution OmniAuth dynamic callback url to authenticate particular objects instead of current_user with no success.
Any help is appreciated.
Found the solution via Devise + Omniauth - How to pass extra parameters along?
I can easily pass the ID as a param to the auth page and get it back via request.env['omniauth.params']
I have to run some code (subscription to an external mailing list) when a new user is created with OmniAuth (any strategy). The setup is pretty much identical to Ryan Bates' screencast:
http://railscasts.com/episodes/241-simple-omniauth?view=asciicast
So far I haven't found a suitable point to hook in the code in the middleware. And when control is returned to the Rails level, the data is passed as user = User.from_omniauth(env["omniauth.auth"]) and nothing indicates whether the user has just been created or not.
A workaround could be a flag on the user which defaults to false and is set to true in session#create. But there has to be a better way, hasn't there? :-)
Thanks for your hints!
You can use the :params option to build a URL, like this
omniauth_authorize_path(:user, :facebook, {var: 'value', var2: 'value2'}
and then in the callback you will get in back in the request.env['omniauth.params']
Some examples here - https://github.com/intridea/omniauth/issues/390
Also here- Passing random url params to OmniAuth
In my Rails FB app, when running in the canvas, if I go to "/users", instead of GETting the index page, it POSTs and creates a new user.
That only happens when I try to access the URL directly. When I use the "List of users" link on the app, it works as expected.
Why is that?
that's just how FB does it. They post data with each query as well.
Facebook sends everything as POST which brakes RESTful routes. There is a way to fix it though. If incoming POST request contains signed_request parameter you can assume it was converted from GET to POST by Facebook.
Rack::Facebook::MethodFix middleware fixes the problem automagically. You can use it with something like:
# Basic usage
use Rack::Facebook::MethodFix
# Also validate signed_request
use Rack::Facebook::MethodFix, :secret_id => "c561df165eacdd6e32672c9eaee10318"
# Do not apply request method fix to admin urls.
use Rack::Facebook::MethodFix, :exclude => proc { |env| env["PATH_INFO"].match(/^\/admin/) }
or if you are using Rails then
config.middleware.use Rack::Facebook::MethodFix
I need to pass some parameters to callback action. Judging from the source code, OmniAuth should add query string to callback URL but strangely it does not. When I open
/auth/facebook?from=partner
...and get redirected to Facebook, return_url is just
/auth/facebook/callback
...without any parameters.
After struggling with all the above answers, I figured out what to do regarding Facebook, which by default does not display the params in request.env["omniauth.auth"].
So -- If you are using a query string for the callback, similar to something like this:
"/auth/facebook?website_id=#{#website.id}"
The only way to get that website_id param is by using request.env["omniauth.params"]. NOTE: MAKE SURE YOU USE omniauth.params and not omniauth.auth -- this one tripped me up for a while.
Then, to test this out, you can inspect it within your controller action (notice the RAISE line...):
def create
raise request.env["omniauth.params"].to_yaml
# the rest of your create action code...
end
You should see your parameter there. Great. Now, go back to your controller and remove that RAISE line. Then, you can access the param as follows in your controller action:
params = request.env["omniauth.params"]
website_id = params["website_id"]
NOTE: in params["website_id"] you need to use quotes and NOT a symbol.
I guess the cookie thing works but why do all that when you can use the state variable as documented here: https://github.com/mkdynamic/omniauth-facebook
This is how I used it:
when creating the url you can just add state in the Query String and it will be available in the callback url as well.
user_omniauth_authorize_path(:facebook, :display => 'page', :state=>'123') %>
now the callback url will be
http://localhost:3000/users/auth/facebook/callback?state=123&code=ReallyLongCode#_=_
Now in the callback handler you can process the state
You can use the :params options, as in
omniauth_authorize_path(:user, :facebook, var: 'value', var2: 'value2' )
and later in the callback you can access request.env['omniauth.params'] to get the hash! :)
(copied from this answer)
What you want to do is dynamically set your callback to include the partner name in the url (not the url parameters), on a per authentication transaction basis, depending on which partner was involved. This means setting the callback url dynamically, for each authentication request. See this blog post to get started. The callback url automatically drops the url parameters, as you've noticed, so doing this with parameters won't work.
So, if instead of trying to pass the partner name/id in as a parameter (which is dropped), you structured your routes so that the partner_id and OmniAuth provider were part of the callback url, then you'd have something like:
/auth/:omniauth_provider/callback/:partner_id
...where a valid callback would be something like
/auth/facebook/callback/123456
...then you would know that a given callback came in from facebook, with partner id 123456
OmniAuth already has a built-in way to know where the user was, it's called "origin" as documented here:
https://github.com/intridea/omniauth/wiki/Saving-User-Location
You know, I think I might be trying to solve this the hard way.
Cookies might be the answer. I think you can solve this by having your login action store a cookie, and then redirecting to the proper /auth/:provider path for authentication, and when the callback is triggered (in SessionsController#create), you just read the cookie back to know where to redirect them to.
So, right now, your "login with facebook" link (or whatever you have you in your app) probably goes to /auth/facebook. Instead if you created a custom action like
POST /partner_auth
...and called it with the url...
POST example.com/partner_auth?from=partner&provider=facebook
Then you might have a controller like:
class PartnerAuth < ApplicationController
def create
cookies[:from] = params[:from] # creates a cookie storing the "from" value
redirect_to "auth/#{params[:provider]"
end
end
Then in the SessionsController#create action, you would have...
def create
...
destination = cookies[:from]
cookies[:from].delete
redirect_to destination # or whatever the appropriate thing is for your
# app to do with the "from" information
end
I tried to build a demo app to accomplish what I'd outlined in the other answer, but you're right - it was too complicated to try to dynamically inject a custom callback into the OmniAuth code. There is a configuration option to override the default callback, but it doesn't appear to be easy to set it dynamically.
So, it dawned on me that cookies would be way simpler, user-specific, and since you theoretically only need to store this from information for a very short time (between when the user tries to authenticate, and when the callback is triggered), it's no big deal to create a cookie, and then delete it when the callback gets hit.
Use the 'state' Variable. Facebook allows the user to set a STATE variable.
Here is how I did it, I appended the AUTH URL with ?state=providername
http://localhost/users/auth/facebook?state=providername
This param is returned to me at Callback as params['providername']
I devised the solution from the original Omniauth Path Method
user_omniauth_authorize_path(:facebook, :display => 'page', :state=>'123') %>
I have the ability in the app to load /users/auth/facebook to connect to facebook. I want to be able to know where the request came from. Whether it was from a user who is registering with facebook, or a existing user who simply wants to connect with facebook. Based on the type, the responses are very different.
How can I pass a param along to omniauth when authenticating. I tried doing:
/users/auth/facebook?connect_action=signup_connect_to_facebook
But that connect_action param didn't make it when it hit AuthenticationsController#Create
Ideas? Thansk
You have to use the :params options, as in
omniauth_authorize_path(:user, :facebook, var: 'value', var2: 'value2' )
and later in the callback you can access request.env['omniauth.params'] to get the hash! :)
If the request is made from different pages in your application, you can examine the request.env['omniauth.origin']. Omniauth saves this variable automatically.
Here is a more detailed explanation
As far as passing custom parameters, I have tried to do this unsuccessfully. The workaround is to store it in the session before going to the provider as explained here.
Hope this helps you.
For facebook use the 'state' parameter and pass what you want, but don't forget the encode.
/users/auth/facebook?state=parameter
You could send the parameter as a url form encoded json and then in the callback parse it.