Allow modules to set a display name on registration

changelog.d/11927.misc

@@ -0,0 +1 @@
+Use the proper type for the Content-Length header in the `UploadResource`.

changelog.d/12009.feature

@@ -0,0 +1 @@
+Enable modules to set a custom display name when registering a user.

changelog.d/12025.misc

@@ -0,0 +1 @@
+Update the `olddeps` CI job to use an old version of `markupsafe`.

docs/modules/password_auth_provider_callbacks.md

@@ -85,7 +85,7 @@ If the authentication is unsuccessful, the module must return `None`.
 If multiple modules implement this callback, they will be considered in order. If a
 callback returns `None`, Synapse falls through to the next one. The value of the first
 callback that does not return `None` will be used. If this happens, Synapse will not call
-any of the subsequent implementations of this callback. If every callback return `None`,
+any of the subsequent implementations of this callback. If every callback returns `None`,
 the authentication is denied.
 
 ### `on_logged_out`
@@ -162,10 +162,38 @@ return `None`.
 If multiple modules implement this callback, they will be considered in order. If a
 callback returns `None`, Synapse falls through to the next one. The value of the first
 callback that does not return `None` will be used. If this happens, Synapse will not call
-any of the subsequent implementations of this callback. If every callback return `None`,
+any of the subsequent implementations of this callback. If every callback returns `None`,
 the username provided by the user is used, if any (otherwise one is automatically
 generated).
 
+### `get_displayname_for_registration`
+
+_First introduced in Synapse v1.54.0_
+
+```python
+async def get_displayname_for_registration(
+    uia_results: Dict[str, Any],
+    params: Dict[str, Any],
+) -> Optional[str]
+```
+
+Called when registering a new user. The module can return a display name to set for the
+user being registered by returning it as a string, or `None` if it doesn't wish to force a
+display name for this user.
+
+This callback is called once [User-Interactive Authentication](https://spec.matrix.org/latest/client-server-api/#user-interactive-authentication-api)
+has been completed by the user. It is not called when registering a user via SSO. It is
+passed two dictionaries, which include the information that the user has provided during
+the registration process. These dictionaries are identical to the ones passed to
+[`get_username_for_registration`](#get_username_for_registration), so refer to the
+documentation of this callback for more information about them.
+
+If multiple modules implement this callback, they will be considered in order. If a
+callback returns `None`, Synapse falls through to the next one. The value of the first
+callback that does not return `None` will be used. If this happens, Synapse will not call
+any of the subsequent implementations of this callback. If every callback returns `None`,
+the username will be used (e.g. `alice` if the user being registered is `@alice:example.com`).
+
 ## `is_3pid_allowed`
 
 _First introduced in Synapse v1.53.0_
@@ -194,8 +222,7 @@ The example module below implements authentication checkers for two different lo
     - Is checked by the method: `self.check_my_login`
 - `m.login.password` (defined in [the spec](https://matrix.org/docs/spec/client_server/latest#password-based))
     - Expects a `password` field to be sent to `/login`
-    - Is checked by the method: `self.check_pass` 
-
+    - Is checked by the method: `self.check_pass`
 
 ```python
 from typing import Awaitable, Callable, Optional, Tuple

synapse/config/registration.py

@@ -43,9 +43,6 @@ def read_config(self, config, **kwargs):
             "registration_requires_token", False
         )
         self.registration_shared_secret = config.get("registration_shared_secret")
-        self.register_just_use_email_for_display_name = config.get(
-            "register_just_use_email_for_display_name", False
-        )
 
         self.bcrypt_rounds = config.get("bcrypt_rounds", 12)
 

synapse/handlers/auth.py

@@ -2064,6 +2064,10 @@ def run(*args: Tuple, **kwargs: Dict) -> Awaitable:
     [JsonDict, JsonDict],
     Awaitable[Optional[str]],
 ]
+GET_DISPLAYNAME_FOR_REGISTRATION_CALLBACK = Callable[
+    [JsonDict, JsonDict],
+    Awaitable[Optional[str]],
+]
 IS_3PID_ALLOWED_CALLBACK = Callable[[str, str, bool], Awaitable[bool]]
 
 
@@ -2080,6 +2084,9 @@ def __init__(self) -> None:
         self.get_username_for_registration_callbacks: List[
             GET_USERNAME_FOR_REGISTRATION_CALLBACK
         ] = []
+        self.get_displayname_for_registration_callbacks: List[
+            GET_DISPLAYNAME_FOR_REGISTRATION_CALLBACK
+        ] = []
         self.is_3pid_allowed_callbacks: List[IS_3PID_ALLOWED_CALLBACK] = []
 
         # Mapping from login type to login parameters
@@ -2099,6 +2106,9 @@ def register_password_auth_provider_callbacks(
         get_username_for_registration: Optional[
             GET_USERNAME_FOR_REGISTRATION_CALLBACK
         ] = None,
+        get_displayname_for_registration: Optional[
+            GET_DISPLAYNAME_FOR_REGISTRATION_CALLBACK
+        ] = None,
     ) -> None:
         # Register check_3pid_auth callback
         if check_3pid_auth is not None:
@@ -2148,6 +2158,11 @@ def register_password_auth_provider_callbacks(
                 get_username_for_registration,
             )
 
+        if get_displayname_for_registration is not None:
+            self.get_displayname_for_registration_callbacks.append(
+                get_displayname_for_registration,
+            )
+
         if is_3pid_allowed is not None:
             self.is_3pid_allowed_callbacks.append(is_3pid_allowed)
 
@@ -2350,6 +2365,49 @@ async def get_username_for_registration(
 
         return None
 
+    async def get_displayname_for_registration(
+        self,
+        uia_results: JsonDict,
+        params: JsonDict,
+    ) -> Optional[str]:
+        """Defines the display name to use when registering the user, using the
+        credentials and parameters provided during the UIA flow.
+
+        Stops at the first callback that returns a tuple containing at least one string.
+
+        Args:
+            uia_results: The credentials provided during the UIA flow.
+            params: The parameters provided by the registration request.
+
+        Returns:
+            A tuple which first element is the display name, and the second is an MXC URL
+            to the user's avatar.
+        """
+        for callback in self.get_displayname_for_registration_callbacks:
+            try:
+                res = await callback(uia_results, params)
+
+                if isinstance(res, str):
+                    return res
+                elif res is not None:
+                    # mypy complains that this line is unreachable because it assumes the
+                    # data returned by the module fits the expected type. We just want
+                    # to make sure this is the case.
+                    logger.warning(  # type: ignore[unreachable]
+                        "Ignoring non-string value returned by"
+                        " get_displayname_for_registration callback %s: %s",
+                        callback,
+                        res,
+                    )
+            except Exception as e:
+                logger.error(
+                    "Module raised an exception in get_displayname_for_registration: %s",
+                    e,
+                )
+                raise SynapseError(code=500, msg="Internal Server Error")
+
+        return None
+
     async def is_3pid_allowed(
         self,
         medium: str,

synapse/module_api/__init__.py

@@ -71,6 +71,7 @@
 from synapse.handlers.auth import (
     CHECK_3PID_AUTH_CALLBACK,
     CHECK_AUTH_CALLBACK,
+    GET_DISPLAYNAME_FOR_REGISTRATION_CALLBACK,
     GET_USERNAME_FOR_REGISTRATION_CALLBACK,
     IS_3PID_ALLOWED_CALLBACK,
     ON_LOGGED_OUT_CALLBACK,
@@ -317,6 +318,9 @@ def register_password_auth_provider_callbacks(
         get_username_for_registration: Optional[
             GET_USERNAME_FOR_REGISTRATION_CALLBACK
         ] = None,
+        get_displayname_for_registration: Optional[
+            GET_DISPLAYNAME_FOR_REGISTRATION_CALLBACK
+        ] = None,
     ) -> None:
         """Registers callbacks for password auth provider capabilities.
 
@@ -328,6 +332,7 @@ def register_password_auth_provider_callbacks(
             is_3pid_allowed=is_3pid_allowed,
             auth_checkers=auth_checkers,
             get_username_for_registration=get_username_for_registration,
+            get_displayname_for_registration=get_displayname_for_registration,
         )
 
     def register_background_update_controller_callbacks(

synapse/rest/client/register.py

@@ -695,26 +695,18 @@ async def on_POST(self, request: SynapseRequest) -> Tuple[int, JsonDict]:
                 session_id
             )
 
-            # TODO: This won't be needed anymore once https://github.com/matrix-org/matrix-dinsic/issues/793
-            #  is resolved.
-            desired_display_name = body.get("display_name")
-            if auth_result:
-                if LoginType.EMAIL_IDENTITY in auth_result:
-                    address = auth_result[LoginType.EMAIL_IDENTITY]["address"]
-                    if (
-                        self.hs.config.registration.register_just_use_email_for_display_name
-                    ):
-                        desired_display_name = address
-                    else:
-                        # Custom mapping between email address and display name
-                        desired_display_name = _map_email_to_displayname(address)
+            display_name = await (
+                self.password_auth_provider.get_displayname_for_registration(
+                    auth_result, params
+                )
+            )
 
             registered_user_id = await self.registration_handler.register_user(
                 localpart=desired_username,
                 password_hash=password_hash,
                 guest_access_token=guest_access_token,
-                default_display_name=desired_display_name,
                 threepid=threepid,
+                default_display_name=display_name,
                 address=client_addr,
                 user_agent_ips=entries,
             )
@@ -876,60 +868,6 @@ async def _do_guest_registration(
         return 200, result
 
 
-def cap(name: str) -> str:
-    """Capitalise parts of a name containing different words, including those
-    separated by hyphens.
-    For example, 'John-Doe'
-
-    Args:
-        The name to parse
-    """
-    if not name:
-        return name
-
-    # Split the name by whitespace then hyphens, capitalizing each part then
-    # joining it back together.
-    capatilized_name = " ".join(
-        "-".join(part.capitalize() for part in space_part.split("-"))
-        for space_part in name.split()
-    )
-    return capatilized_name
-
-
-def _map_email_to_displayname(address: str) -> str:
-    """Custom mapping from an email address to a user displayname
-
-    Args:
-        address: The email address to process
-    Returns:
-        The new displayname
-    """
-    # Split the part before and after the @ in the email.
-    # Replace all . with spaces in the first part
-    parts = address.replace(".", " ").split("@")
-
-    # Figure out which org this email address belongs to
-    org_parts = parts[1].split(" ")
-
-    # If this is a ...matrix.org email, mark them as an Admin
-    if org_parts[-2] == "matrix" and org_parts[-1] == "org":
-        org = "Tchap Admin"
-
-    # Is this is a ...gouv.fr address, set the org to whatever is before
-    # gouv.fr. If there isn't anything (a @gouv.fr email) simply mark their
-    # org as "gouv"
-    elif org_parts[-2] == "gouv" and org_parts[-1] == "fr":
-        org = org_parts[-3] if len(org_parts) > 2 else org_parts[-2]
-
-    # Otherwise, mark their org as the email's second-level domain name
-    else:
-        org = org_parts[-2]
-
-    desired_display_name = cap(parts[0]) + " [" + cap(org) + "]"
-
-    return desired_display_name
-
-
 def _calculate_registration_flows(
     config: HomeServerConfig, auth_handler: AuthHandler
 ) -> List[List[str]]:

synapse/rest/media/v1/upload_resource.py

@@ -49,10 +49,14 @@ async def _async_render_OPTIONS(self, request: SynapseRequest) -> None:
 
     async def _async_render_POST(self, request: SynapseRequest) -> None:
         requester = await self.auth.get_user_by_req(request)
-        content_length = request.getHeader("Content-Length")
-        if content_length is None:
+        raw_content_length = request.getHeader("Content-Length")
+        if raw_content_length is None:
             raise SynapseError(msg="Request must specify a Content-Length", code=400)
-        if int(content_length) > self.max_upload_size:
+        try:
+            content_length = int(raw_content_length)
+        except ValueError:
+            raise SynapseError(msg="Content-Length value is invalid", code=400)
+        if content_length > self.max_upload_size:
             raise SynapseError(
                 msg="Upload request body is too large",
                 code=413,
@@ -66,7 +70,8 @@ async def _async_render_POST(self, request: SynapseRequest) -> None:
                 upload_name: Optional[str] = upload_name_bytes.decode("utf8")
             except UnicodeDecodeError:
                 raise SynapseError(
-                    msg="Invalid UTF-8 filename parameter: %r" % (upload_name), code=400
+                    msg="Invalid UTF-8 filename parameter: %r" % (upload_name_bytes,),
+                    code=400,
                 )
 
         # If the name is falsey (e.g. an empty byte string) ensure it is None.