Replicate Postman Oauth 2.0 using Python - python-3.x

Question

I have this Authorization request that works.
How can I replicate it in Python?
I am using an Azure AD to authenticate the access.

Answer 1

Since you are working with python, your case is a : Oauth2 login for SSR web applications with Microsoft
Goal
Get an access_token from interactive login using the oauth2 authorization code grant
Steps
Here I will list all the steps required to do it with any language
Create a web with session with at least these endpoints
/ : home page
/callback : server route or path able to receive query params like /callback?code=123456. This along with your base domain will be called redirect_uri. Sample : http://localhost:8080/callback or http://acme.com/callback
Create and configure an app in Azure Dev Console. Same process is in Google, Facebook, Linkedin, etc. As a result you should have a clientId, clientSecret and a redirect url
Create a simple web with classic session in which if user is not logged-in, redirect (302) to this url:
https://login.microsoftonline.com/common/oauth2/v2.0/authorize?client_id=foo&response_type=code&redirect_uri=foo&response_mode=query&scope=offline_access%20user.read%20mail.read
clientid and redirect_uri are important here and should be the same of previous step
After that, browser should redirect the user to the platform login
If user enters valid credentials and accepts the consent warning, Microsoft will perform another redirect (302) to the provided redirect_uri but with special value: The auth code
http://acme.com/callback?code=123456798
In the backend of /callback get the code and send it to this new endpoint
Add a client_id & client_secret parameters
Add a code parameter with the code sent by microsoft
Add a redirect_uri parameter with previously used and registered on azure. Sample http://acme.com/callback or http://localhost:8080/callback
Add a grant_type parameter with a value of authorization_code
Issue the HTTP POST request with content-type: application/x-www-form-urlencoded
You should get a response with the precious access_token:
{
token_type: 'Bearer',
scope: 'Mail.Read User.Read profile openid email',
expires_in: 5020,
ext_expires_in: 5020,
access_token: 'eyJ0oVlKhZHsvMhRydQ',
refresh_token: 's_Rcrqf6xMaWcPHJxRFwCQFkL_qUYqBLM71UN6'
}
You could do with this token, whatever you configured in azure. Sample: If you want to access to user calendar, profile, etc on behalf of the user, you should have registered this in the azure console. So the clientid is related to that and human user will be prompted with something like this
Libraries
There is some libraries provided by microsoft (c#, nodejs) which will save you a little work. Anyway the previous explanation are very detailed.
Advice
Read about oauth2 spec: https://oauth.net/2/
Read about oauth2 authorization code flow login before the implementation with python
https://www.digitalocean.com/community/tutorials/an-introduction-to-oauth-2
https://auth0.com/docs/get-started/authentication-and-authorization-flow/authorization-code-flow
https://github.com/msusdev/microsoft_identity_platform_dev/blob/main/presentations/auth_users_msalnet.md
Check this to understand how configure the azure web console: https://learn.microsoft.com/en-us/azure/active-directory/develop/quickstart-register-app
Check my gist https://gist.github.com/jrichardsz/5b8ba730978fce7a7c585007d3fd06b4