Remove old register_mxid_from_3pid setting

Author: babolivier

docs/sample_config.yaml

@@ -1318,13 +1318,6 @@ oembed:
 #
 #disable_msisdn_registration: true
 
-# Derive the user's matrix ID from a type of 3PID used when registering.
-# This overrides any matrix ID the user proposes when calling /register
-# The 3PID type should be present in registrations_require_3pid to avoid
-# users failing to register if they don't specify the right kind of 3pid.
-#
-#register_mxid_from_3pid: email
-
 # Uncomment to set the display name of new users to their email address,
 # rather than using the default heuristic.
 #

synapse/config/registration.py

@@ -44,7 +44,6 @@ def read_config(self, config, **kwargs):
             "registration_requires_token", False
         )
         self.registration_shared_secret = config.get("registration_shared_secret")
-        self.register_mxid_from_3pid = config.get("register_mxid_from_3pid")
         self.register_just_use_email_for_display_name = config.get(
             "register_just_use_email_for_display_name", False
         )
@@ -232,13 +231,6 @@ def generate_config_section(self, generate_secrets=False, **kwargs):
         #
         #disable_msisdn_registration: true
 
-        # Derive the user's matrix ID from a type of 3PID used when registering.
-        # This overrides any matrix ID the user proposes when calling /register
-        # The 3PID type should be present in registrations_require_3pid to avoid
-        # users failing to register if they don't specify the right kind of 3pid.
-        #
-        #register_mxid_from_3pid: email
-
         # Uncomment to set the display name of new users to their email address,
         # rather than using the default heuristic.
         #

synapse/rest/client/register.py

@@ -635,73 +635,6 @@ async def on_POST(self, request: SynapseRequest) -> Tuple[int, JsonDict]:
                             400, "%s is already in use" % medium, Codes.THREEPID_IN_USE
                         )
 
-        if self.hs.config.registration.register_mxid_from_3pid:
-            # override the desired_username based on the 3PID if any.
-            # reset it first to avoid folks picking their own username.
-            desired_username = None
-
-            # we should have an auth_result at this point if we're going to progress
-            # to register the user (i.e. we haven't picked up a registered_user_id
-            # from our session store), in which case get ready and gen the
-            # desired_username
-            if auth_result:
-                if (
-                    self.hs.config.registration.register_mxid_from_3pid == "email"
-                    and LoginType.EMAIL_IDENTITY in auth_result
-                ):
-                    address = auth_result[LoginType.EMAIL_IDENTITY]["address"]
-                    desired_username = synapse.types.strip_invalid_mxid_characters(
-                        address.replace("@", "-").lower()
-                    )
-
-                    # find a unique mxid for the account, suffixing numbers
-                    # if needed
-                    while True:
-                        try:
-                            await self.registration_handler.check_username(
-                                desired_username,
-                                guest_access_token=guest_access_token,
-                                assigned_user_id=registered_user_id,
-                            )
-                            # if we got this far we passed the check.
-                            break
-                        except SynapseError as e:
-                            if e.errcode == Codes.USER_IN_USE:
-                                m = re.match(r"^(.*?)(\d+)$", desired_username)
-                                if m:
-                                    desired_username = m.group(1) + str(
-                                        int(m.group(2)) + 1
-                                    )
-                                else:
-                                    desired_username += "1"
-                            else:
-                                # something else went wrong.
-                                break
-
-                    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)
-                elif (
-                    self.hs.config.registration.register_mxid_from_3pid == "msisdn"
-                    and LoginType.MSISDN in auth_result
-                ):
-                    desired_username = auth_result[LoginType.MSISDN]["address"]
-                else:
-                    raise SynapseError(
-                        400, "Cannot derive mxid from 3pid; no recognised 3pid"
-                    )
-
-        if desired_username is not None:
-            await self.registration_handler.check_username(
-                desired_username,
-                guest_access_token=guest_access_token,
-                assigned_user_id=registered_user_id,
-            )
-
         if registered_user_id is not None:
             logger.info(
                 "Already registered user ID %r for this session", registered_user_id