Add config doc generation command to lint.sh and add missing config schema. (#18522)

Follows: #17892, #18456

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Add config doc generation command to lint.sh 

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Add missing `user_types` config schema 

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---------

Signed-off-by: Olivier 'reivilibre <oliverw@matrix.org>

changelog.d/18522.doc

@@ -0,0 +1 @@
+Generate config documentation from JSON Schema file.

docs/usage/configuration/config_documentation.md

@@ -764,22 +764,23 @@ max_event_delay_duration: 24h
 ---
 ### `user_types`
 
-Configuration settings related to the user types feature.
+*(object)* Configuration settings related to the user types feature.
 
 This setting has the following sub-options:
-* `default_user_type`: The default user type to use for registering new users when no value has been specified.
-  Defaults to none.
-* `extra_user_types`: Array of additional user types to allow. These are treated as real users. Defaults to [].
+
+* `default_user_type` (string|null): The default user type to use for registering new users when no value has been specified. Defaults to none. Defaults to `null`.
+
+* `extra_user_types` (list): Array of additional user types to allow. These are treated as real users. Defaults to `[]`.
 
 Example configuration:
 ```yaml
 user_types:
-    default_user_type: "custom"
-    extra_user_types:
-      - "custom"
-      - "custom2"
+  default_user_type: custom
+  extra_user_types:
+  - custom
+  - custom2
 ```
-
+---
 ## Homeserver blocking
 
 Useful options for Synapse admins.

schema/synapse-config.schema.yaml

@@ -912,6 +912,24 @@ properties:
     default: null
     examples:
       - 24h
+  user_types:
+    type: object
+    description: >-
+      Configuration settings related to the user types feature.
+    properties:
+      default_user_type:
+        type: ["string", "null"]
+        description: "The default user type to use for registering new users when no value has been specified. Defaults to none."
+        default: null
+      extra_user_types:
+        type: array
+        description: "Array of additional user types to allow. These are treated as real users."
+        items:
+          type: string
+        default: []
+    examples:
+      - default_user_type: "custom"
+        extra_user_types: ["custom", "custom2"]
   admin_contact:
     type: ["string", "null"]
     description: How to reach the server admin, used in `ResourceLimitError`.

scripts-dev/lint.sh

@@ -139,3 +139,6 @@ cargo-fmt
 
 # Ensure type hints are correct.
 mypy
+
+# Generate configuration documentation from the JSON Schema
+./scripts-dev/gen_config_documentation.py schema/synapse-config.schema.yaml > docs/usage/configuration/config_documentation.md