How to run module code on a specific page/path? So, I'm working on an implementation where users will be redirected to a specific path on a Drupal 7 site with query parameters appended to the URL in an Oauth2 scenario (e.g. www.mysite.com/mypath&amp;code&amp;scope) which the D7 should process and respond to. How does one specify within a custom module to run the code a particular path? Would this be achieved through a code block?
You can use OAuth2 Authentication. Some details about it, from its project page:

... allows users to log into your Drupal site authenticating against a remote identity provider (IDP) via OAuth2.
That is, if a user's credentials can be used to retrieve a valid access token, he/she will be logged into the site with those credentials and the token will be added to his/her session. If the user doesn't exist yet, it will be created.