doc: added mailing env vars to readme

README.md

@@ -49,13 +49,20 @@ This is the Admin UI for the Canonical Identity Platform.
   middleware is enabled default to `true`
 - `AUTHENTICATION_ENABLED`: flag defining if the OAuth authentication middleware
   is enabled, default to `false`
-- `OIDC_ISSUER`: URL of the OIDC provider 
+- `OIDC_ISSUER`: URL of the OIDC provider
 - `OAUTH2_CLIENT_ID`: OAuth2 client ID used for authentication purposes
 - `OAUTH2_CLIENT_SECRET`: OAuth2 client secret used for authentication purposes
 - `OAUTH2_REDIRECT_URI`: URI used by the Oauth2 provider for the redirecting callback
 - `OAUTH2_CODEGRANT_SCOPES`: OAuth2 scopes, defaults to `openid,offline_access`
 - `OAUTH2_AUTH_COOKIES_ENCRYPTION_KEY`: 32 bytes string used for encrypting cookies
 - `ACCESS_TOKEN_VERIFICATION_STRATEGY`: OAuth2 verification startegy, one of `jwks` or `userinfo``
+- `MAIL_HOST`: host of the mail server (required)
+- `MAIL_PORT`: port exposed by the mail server (required)
+- `MAIL_USERNAME`: username to use for the simple authentication on the mail server (if present, both username and
+  password are used)
+- `MAIL_PASSWORD`: password to use for the simple authentication on the mail server
+- `MAIL_FROM_ADDRESS`: email address sending the email (required)
+- `MAIL_SEND_TIMEOUT_SECONDS`: timeout used to send emails (defaults to 15 seconds)
 
 ## Development setup