auth_stackoverflow.pl -- Enable login with stackexchange

This module allows for configures _login with Stack exchange. To enable this module:

1. Follow these steps to register your application on Stack Apps. Get the following info:
   • The client ID
   • The client secret
   • The key
   • Register a redirect url. To test from localhost, this should be http://localhost:3050/oauth2/stackexchange/reply
2. COPY this file to config-enabled
3. EDIT the server attributes

 oauth2:server_attribute(?ServerID, ?Attribute, ?Value)[multifile]

Declare properties of an oauth2 identity provider. The values below are for StackExchange server.

EDIT:

• url: base URL of the stackexchange authentication server
• api_endpoint: Stack Apps API endpoint
• redirect_uri: our location
• client_id: Client Id from Stack Apps
• client_secret: Client Secret from Stack Apps
• key: Key from Stack Apps to access their API (/me)
• site: Stack exchange site for which to ask info

See also

- swish(lib/oauth2) for a description of the attributes.

 stackexchange_me(+AccessToken, -Info)[private]

Stack exchange does not support the oauth2 user_info endpoint. Instead, we must use the =/me= API. This is a little unlucky as we need to duplicate some infrastructure from the generic oauth2.pl module.

 read_reply2(+Code, +ContentType, +Stream, -Dict) is det[private]

Read the server reply as a dict. Normally, the reply is a JSON object, but stackexchange seems to send it as a www-form-encoded string.

 stackexchange_logout(+Request)[private]

Logout by removing the session data

 swish_config:user_info(+Request, ?Server, -Info:dict) is semidet[multifile]

True if Info represents describes the currently logged in user.

 map_user_info(+OAuthInfo, -UserInfo) is det[private]

u{user:User, group:Group, name:Name, email:Email}

 uri_extend(+Base:atom, +Rel:atom, +Query:list, -URI:atom) is det[private]

Create a URI from Base, A relative URI and a query.

 uri_extend_query(+URI0:atom, +Query:list, -URI:atom) is det[private]

Extend a URI with a query. If URI0 already has a query, keep all parameters that do not conflict.