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docs/content/config/environment.md

@@ -55,10 +55,13 @@ The Group ID assigned to the static vmail group for `/var/mail` (_Mail storage m
 Configures the provisioning source of user accounts (including aliases) for user queries and authentication by services managed by DMS (_Postfix and Dovecot_).
 
 !!! tip "OAuth2 Support"
+
     Presently DMS supports OAuth2 only as an supplementary authentication method. 
+
     - A third-party service must provide a valid token for the user which Dovecot validates with the authentication service provider. To enable this feature reference the [OAuth2 configuration example guide][docs::auth::oauth2-config-guide].
     - User accounts must be provisioned to receive mail via one of the supported `ACCOUNT_PROVISIONER` providers.
     - User provisioning via OAUTH2 is planned for the future, see [this tracking issue](https://github.com/docker-mailserver/docker-mailserver/issues/2713).
+
 [docs::auth::oauth2-config-guide]: ./advanced/auth-oauth2.md
 
 - **empty** => use FILE
@@ -620,7 +623,8 @@ Enable or disable `getmail`.
 
 ##### OAUTH2_INTROSPECTION_URL
 
-- => Specify the user info endpoint URL of the oauth2 provider. E.g. `https://oauth2.example.com/userinfo/`, where the trailing slash is MANDATORY (at least for Authentik)
+- => Specify the user info endpoint URL of the oauth2 provider (_eg: `https://oauth2.example.com/userinfo/`_)
+
 #### LDAP
 
 ##### LDAP_START_TLS

mailserver.env

@@ -427,6 +427,7 @@ GETMAIL_POLL=5
 ENABLE_OAUTH2=
 
 # Specify the user info endpoint URL of the oauth2 provider. The trailing slash is MANDATORY (at least for Authentik)
+# Example: https://oauth2.example.com/userinfo/
 OAUTH2_INTROSPECTION_URL=
 
 # -----------------------------------------------

target/dovecot/dovecot-oauth2.conf.ext

@@ -1 +1,2 @@
 introspection_url =
+introspection_mode = auth

test/config/oauth2/provider.py

@@ -1,3 +1,8 @@
+# OAuth2 mock service
+#
+# Dovecot will query this service with the token it was provided.
+# If the session for the token is valid, a response provides an attribute to perform a UserDB lookup on (default: email).
+
 import json
 import base64
 from http.server import BaseHTTPRequestHandler, HTTPServer
@@ -25,6 +30,7 @@ class HTTPRequestHandler(BaseHTTPRequestHandler):
             self.end_headers()
             return
         auth = auth.split()[1]
+        # Valid session, respond with JSON containing the expected `email` claim to match as Dovecot username:
         if auth == token:
             self.send_response(200)
             self.send_header('Content-Type', 'application/json')

test/tests/serial/mail_with_oauth2.bats

@@ -32,7 +32,7 @@ function setup_file() {
   # Add OAUTH2 configuration so that Dovecot can reach out to our mock provider (CONTAINER2)
   local ENV_OAUTH2_CONFIG=(
     --env ENABLE_OAUTH2=1
-    --env OAUTH2_INTROSPECTION_URL=http://oauth2.example.test/
+    --env OAUTH2_INTROSPECTION_URL=http://oauth2.example.test/userinfo/
   )
 
   export CONTAINER_NAME=${CONTAINER1_NAME}
@@ -45,7 +45,7 @@ function setup_file() {
 
   _init_with_defaults
   _common_container_setup 'CUSTOM_SETUP_ARGUMENTS'
-  _wait_for_smtp_port_in_container
+  _wait_for_tcp_port_in_container 143
 
   # Set default implicit container fallback for helpers:
   export CONTAINER_NAME=${CONTAINER1_NAME}
@@ -58,8 +58,9 @@ function teardown_file() {
 
 
 @test "oauth2: imap connect and authentication works" {
+  # An initial connection needs to be made first, otherwise the auth attempt fails
   _run_in_container_bash 'nc -vz 0.0.0.0 143'
-  _run_in_container_bash 'sleep 5'
+
   _run_in_container_bash 'nc -w 1 0.0.0.0 143 < /tmp/docker-mailserver-test/auth/imap-oauth2-auth.txt'
   assert_output --partial 'Examine completed'
 }