django-paytm-oauth

django-paytm-oauth is a Django based application for consuming Oauth 2 implementation of Paytm.

##Flow

Paytm oauth is consumer side implementation of Oauth 2.0. The steps involved in the flow are explained are below.

• Authentication Request : User clicks on the Login with Paytm button which redirects to PAYTMOAUTH_PROVIDER_URL + PAYTMOAUTH_AUTHORIZATION_ENDPOINT and the following parameters are passed

  • response_type
  • client_id
  • scope
  • redirect_uri

• Authentication Grant : User enters his credentials and then the server authenticates the user. As a result of this authorization, an authorization token is passed. This is authorization grant which is passed to the application. The PAYTMOAUTH_REDIRECT_URL receives this response.

• Authorization Request : Now after the application has received user's authorization grant, it authorizes itself by passing its id(CLIENT_ID) and secret(CLIENT_SECRET). The url endpoint here will be PAYTMOAUTH_AUTHENTICATION_ENDPOINT. This is a server to server call where in authorization header is passed which contains the credentials of the client. Along with the header, following parameters are passed in the body of the post request

  • grant_type
  • code
  • client_id
  • scope

  Here grant_type is generally authorization_code and the value of code is the authorization token received from the previous step. This way the authorization server knows that the application is currently talking about which user. This is a server to server call where in no user is involved.

• Authorization Grant : The authorization server authorizes the request by the application. It authenticates whether the app is genuine or not by validating given client id and client secret. The server passes an access_token in the response. This response is received at PAYTMOAUTH_REDIRECT_URL.

• Protected Resource Access : This is again a server to server call where the application uses the access_token received in the previous step as a header. Here the url endpoint will be PAYTMOUATH_RESOURCE_ACCESS_ENDPOINT.

• Grant Protected Resource : The server replies in response to the previous step with the protected resource being requested.

##Installation

Through pip

pip install paytm-oauth

django-paytm-oauth is available as a git repository. It can be installed by

git clone https://github.com/paytm/django-paytm-oauth.git
cd django-paytm-oauth
python setup.py install

##Configuration

• After installing, you need to add paytmoauth in your INSTALLED_APPS like

    # settings.py
    INSTALLED_APPS = (
        ...
        'paytmoauth',
    )

• Include urls in your root urls urlpatterns like

    # urls.py
    urlpatterns = [
        ...
        url(r'^oauth/', include('paytmoauth.urls')),
    ]

This url should be white-listed. In the above case oauth/callback needs to be white-listed.

• Update your context_processors to include one provided by paytmoauth like

    TEMPLATES = [
        ...
        'OPTIONS': {
            'context_processors': [
                ...
                'paytmoauth.context_processors.login_url',
            ]
        }
    ]

Through this a context variable namely paytmoauth_login_url will be available in the templates.

• After login page will be redirected to LOGIN_REDIRECT_URL

##Settings

The following variables needs to be defined in the settings

• PAYTMOAUTH_PROVIDER_URL
• PAYTMOAUTH_AUTHORIZATION_ENDPOINT
• PAYTMOAUTH_AUTHENTICATION_ENDPOINT
• PAYTMOUATH_RESOURCE_ACCESS_ENDPOINT
• PAYTMOAUTH_CLIENT_ID
• PAYTMOAUTH_CLIENT_SECRET
• PAYTMOAUTH_SCOPE
• PAYTMOAUTH_REDIRECT_URL