Merge branch 'develop' of github.com:matrix-org/synapse into babolivier/rewrite_is_url

31 files changed, 267 insertions, 64 deletions

diff --git a/CHANGES.md b/CHANGES.md
index 78498c10b5..6618378c06 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -1,8 +1,20 @@
-Synapse 1.55.0rc1 (2022-03-15)
-==============================
+Synapse 1.55.0 (2022-03-22)
+===========================
 
 This release removes a workaround introduced in Synapse 1.50.0 for Mjolnir compatibility. **This breaks compatibility with Mjolnir 1.3.1 and earlier. ([\#11700](https://github.com/matrix-org/synapse/issues/11700))**; Mjolnir users should upgrade Mjolnir before upgrading Synapse to this version.
 
+This release also moves the location of the `synctl` script; see the [upgrade notes](https://github.com/matrix-org/synapse/blob/develop/docs/upgrade.md#synctl-script-has-been-moved) for more details.
+
+
+Internal Changes
+----------------
+
+- Tweak copy for default Single Sign-On account details template to better adhere to mobile app store guidelines. ([\#12265](https://github.com/matrix-org/synapse/issues/12265), [\#12260](https://github.com/matrix-org/synapse/issues/12260))
+
+
+Synapse 1.55.0rc1 (2022-03-15)
+==============================
+
 Features
 --------
 
@@ -38,6 +50,7 @@ Deprecations and Removals
 -------------------------
 
 - **Remove workaround introduced in Synapse 1.50.0 for Mjolnir compatibility. Breaks compatibility with Mjolnir 1.3.1 and earlier. ([\#11700](https://github.com/matrix-org/synapse/issues/11700))**
+- **`synctl` has been moved into into `synapse._scripts` and is exposed as an entry point; see [upgrade notes](https://github.com/matrix-org/synapse/blob/develop/docs/upgrade.md#synctl-script-has-been-moved). ([\#12140](https://github.com/matrix-org/synapse/issues/12140))
 - Remove backwards compatibilty with pagination tokens from the `/relations` and `/aggregations` endpoints generated from Synapse < v1.52.0. ([\#12138](https://github.com/matrix-org/synapse/issues/12138))
 - The groups/communities feature in Synapse has been deprecated. ([\#12200](https://github.com/matrix-org/synapse/issues/12200))
 
@@ -56,7 +69,6 @@ Internal Changes
 - Fix CI not attaching source distributions and wheels to the GitHub releases. ([\#12131](https://github.com/matrix-org/synapse/issues/12131))
 - Remove unused mocks from `test_typing`. ([\#12136](https://github.com/matrix-org/synapse/issues/12136))
 - Give `scripts-dev` scripts suffixes for neater CI config. ([\#12137](https://github.com/matrix-org/synapse/issues/12137))
-- Move `synctl` into `synapse._scripts` and expose as an entry point. ([\#12140](https://github.com/matrix-org/synapse/issues/12140))
 - Move the snapcraft configuration file to `contrib`. ([\#12142](https://github.com/matrix-org/synapse/issues/12142))
 - Enable [MSC3030](https://github.com/matrix-org/matrix-doc/pull/3030) Complement tests in CI. ([\#12144](https://github.com/matrix-org/synapse/issues/12144))
 - Enable [MSC2716](https://github.com/matrix-org/matrix-doc/pull/2716) Complement tests in CI. ([\#12145](https://github.com/matrix-org/synapse/issues/12145))
diff --git a/changelog.d/12036.misc b/changelog.d/12036.misc
new file mode 100644
index 0000000000..d2996730cc
--- /dev/null
+++ b/changelog.d/12036.misc
@@ -0,0 +1 @@
+Rename `shared_rooms` to `mutual_rooms` (MSC2666), as per proposal changes.
\ No newline at end of file
diff --git a/changelog.d/12038.misc b/changelog.d/12038.misc
new file mode 100644
index 0000000000..e2a65726b6
--- /dev/null
+++ b/changelog.d/12038.misc
@@ -0,0 +1 @@
+Remove check on `update_user_directory` for shared rooms handler (MSC2666), and update/expand documentation.
\ No newline at end of file
diff --git a/changelog.d/12250.feature b/changelog.d/12250.feature
new file mode 100644
index 0000000000..29a2724457
--- /dev/null
+++ b/changelog.d/12250.feature
@@ -0,0 +1 @@
+Allow registering admin users using the module API. Contributed by Famedly.
diff --git a/changelog.d/12260.misc b/changelog.d/12260.misc
deleted file mode 100644
index deacf034de..0000000000
--- a/changelog.d/12260.misc
+++ /dev/null
@@ -1 +0,0 @@
-Reword 'Choose your user name' as 'Choose your account name' in the SSO registration template, in order to comply with SIWA guidelines.
\ No newline at end of file
diff --git a/changelog.d/12262.misc b/changelog.d/12262.misc
new file mode 100644
index 0000000000..574ac4752c
--- /dev/null
+++ b/changelog.d/12262.misc
@@ -0,0 +1 @@
+Refuse to start if DB has non-`C` locale, unless config flag `allow_unsafe_db_locale` is set to true.
\ No newline at end of file
diff --git a/changelog.d/12266.misc b/changelog.d/12266.misc
new file mode 100644
index 0000000000..59e2718370
--- /dev/null
+++ b/changelog.d/12266.misc
@@ -0,0 +1 @@
+Optionally include account validity expiration information to experimental [MSC3720](https://github.com/matrix-org/matrix-doc/pull/3720) account status responses.
diff --git a/changelog.d/12269.misc b/changelog.d/12269.misc
new file mode 100644
index 0000000000..ed79cbb528
--- /dev/null
+++ b/changelog.d/12269.misc
@@ -0,0 +1 @@
+Use type stubs for `psycopg2`.
diff --git a/debian/changelog b/debian/changelog
index 09ef24ebb0..7eed6c5b4a 100644
--- a/debian/changelog
+++ b/debian/changelog
@@ -1,3 +1,9 @@
+matrix-synapse-py3 (1.55.0) stable; urgency=medium
+
+  * New synapse release 1.55.0.
+
+ -- Synapse Packaging team <packages@matrix.org>  Tue, 22 Mar 2022 13:59:26 +0000
+
 matrix-synapse-py3 (1.55.0~rc1) stable; urgency=medium
 
   * New synapse release 1.55.0~rc1.
diff --git a/docs/postgres.md b/docs/postgres.md
index de4e2ba4b7..cbc32e1836 100644
--- a/docs/postgres.md
+++ b/docs/postgres.md
@@ -234,12 +234,13 @@ host    all         all             ::1/128     ident
 ### Fixing incorrect `COLLATE` or `CTYPE`
 
 Synapse will refuse to set up a new database if it has the wrong values of
-`COLLATE` and `CTYPE` set, and will log warnings on existing databases. Using
-different locales can cause issues if the locale library is updated from
+`COLLATE` and `CTYPE` set. Synapse will also refuse to start an existing database with incorrect values
+of `COLLATE` and `CTYPE` unless the config flag `allow_unsafe_locale`, found in the 
+`database` section of the config, is set to true. Using different locales can cause issues if the locale library is updated from
 underneath the database, or if a different version of the locale is used on any
 replicas.
 
-The safest way to fix the issue is to dump the database and recreate it with
+If you have a databse with an unsafe locale, the safest way to fix the issue is to dump the database and recreate it with
 the correct locale parameter (as shown above). It is also possible to change the
 parameters on a live database and run a `REINDEX` on the entire database,
 however extreme care must be taken to avoid database corruption.
diff --git a/docs/sample_config.yaml b/docs/sample_config.yaml
index 9336c557b2..53dfd0f3ff 100644
--- a/docs/sample_config.yaml
+++ b/docs/sample_config.yaml
@@ -800,6 +800,12 @@ caches:
 # 'txn_limit' gives the maximum number of transactions to run per connection
 # before reconnecting. Defaults to 0, which means no limit.
 #
+# 'allow_unsafe_locale' is an option specific to Postgres. Under the default behavior, Synapse will refuse to
+# start if the postgres db is set to a non-C locale. You can override this behavior (which is *not* recommended)
+# by setting 'allow_unsafe_locale' to true. Note that doing so may corrupt your database. You can find more information
+# here: https://matrix-org.github.io/synapse/latest/postgres.html#fixing-incorrect-collate-or-ctype and here:
+# https://wiki.postgresql.org/wiki/Locale_data_changes
+#
 # 'args' gives options which are passed through to the database engine,
 # except for options starting 'cp_', which are used to configure the Twisted
 # connection pool. For a reference to valid arguments, see:
diff --git a/docs/workers.md b/docs/workers.md
index 9eb4194e4d..8ac95e39bb 100644
--- a/docs/workers.md
+++ b/docs/workers.md
@@ -528,10 +528,19 @@ the following regular expressions:
 
     ^/_matrix/client/(r0|v3|unstable)/user_directory/search$
 
-When using this worker you must also set `update_user_directory: False` in the
+When using this worker you must also set `update_user_directory: false` in the
 shared configuration file to stop the main synapse running background
 jobs related to updating the user directory.
 
+Above endpoint is not *required* to be routed to this worker. By default,
+`update_user_directory` is set to `true`, which means the main process
+will handle updates. All workers configured with `client` can handle the above
+endpoint as long as either this worker or the main process are configured to
+handle it, and are online.
+
+If `update_user_directory` is set to `false`, and this worker is not running,
+the above endpoint may give outdated results.
+
 ### `synapse.app.frontend_proxy`
 
 Proxies some frequently-requested client endpoints to add caching and remove
diff --git a/setup.py b/setup.py
index 439ed75d72..63da71ad7b 100755
--- a/setup.py
+++ b/setup.py
@@ -108,6 +108,7 @@ CONDITIONAL_REQUIREMENTS["mypy"] = [
     "types-jsonschema>=3.2.0",
     "types-opentracing>=2.4.2",
     "types-Pillow>=8.3.4",
+    "types-psycopg2>=2.9.9",
     "types-pyOpenSSL>=20.0.7",
     "types-PyYAML>=5.4.10",
     "types-requests>=2.26.0",
diff --git a/synapse/__init__.py b/synapse/__init__.py
index 870707f476..f0f224d0bb 100644
--- a/synapse/__init__.py
+++ b/synapse/__init__.py
@@ -68,7 +68,7 @@ try:
 except ImportError:
     pass
 
-__version__ = "1.55.0rc1"
+__version__ = "1.55.0"
 
 if bool(os.environ.get("SYNAPSE_TEST_PATCH_LOG_CONTEXTS", False)):
     # We import here so that we don't have to install a bunch of deps when
diff --git a/synapse/config/database.py b/synapse/config/database.py
index 06ccf15cd9..d7f2219f53 100644
--- a/synapse/config/database.py
+++ b/synapse/config/database.py
@@ -37,6 +37,12 @@ DEFAULT_CONFIG = """\
 # 'txn_limit' gives the maximum number of transactions to run per connection
 # before reconnecting. Defaults to 0, which means no limit.
 #
+# 'allow_unsafe_locale' is an option specific to Postgres. Under the default behavior, Synapse will refuse to
+# start if the postgres db is set to a non-C locale. You can override this behavior (which is *not* recommended)
+# by setting 'allow_unsafe_locale' to true. Note that doing so may corrupt your database. You can find more information
+# here: https://matrix-org.github.io/synapse/latest/postgres.html#fixing-incorrect-collate-or-ctype and here:
+# https://wiki.postgresql.org/wiki/Locale_data_changes
+#
 # 'args' gives options which are passed through to the database engine,
 # except for options starting 'cp_', which are used to configure the Twisted
 # connection pool. For a reference to valid arguments, see:
diff --git a/synapse/config/server.py b/synapse/config/server.py
index ef853c12be..bcdcf2f264 100644
--- a/synapse/config/server.py
+++ b/synapse/config/server.py
@@ -676,6 +676,10 @@ class ServerConfig(Config):
         ):
             raise ConfigError("'custom_template_directory' must be a string")
 
+        self.use_account_validity_in_account_status: bool = (
+            config.get("use_account_validity_in_account_status") or False
+        )
+
         self.identity_server_rewrite_map: Dict[str, str] = (
             config.get("rewrite_identity_server_base_urls") or {}
         )
diff --git a/synapse/handlers/account.py b/synapse/handlers/account.py
index d5badf635b..c05a14304c 100644
--- a/synapse/handlers/account.py
+++ b/synapse/handlers/account.py
@@ -26,6 +26,10 @@ class AccountHandler:
         self._main_store = hs.get_datastores().main
         self._is_mine = hs.is_mine
         self._federation_client = hs.get_federation_client()
+        self._use_account_validity_in_account_status = (
+            hs.config.server.use_account_validity_in_account_status
+        )
+        self._account_validity_handler = hs.get_account_validity_handler()
 
     async def get_account_statuses(
         self,
@@ -106,6 +110,13 @@ class AccountHandler:
                 "deactivated": userinfo.is_deactivated,
             }
 
+            if self._use_account_validity_in_account_status:
+                status[
+                    "org.matrix.expired"
+                ] = await self._account_validity_handler.is_user_expired(
+                    user_id.to_string()
+                )
+
         return status
 
     async def _get_remote_account_statuses(
diff --git a/synapse/module_api/__init__.py b/synapse/module_api/__init__.py
index aa8256b36f..a628faaf65 100644
--- a/synapse/module_api/__init__.py
+++ b/synapse/module_api/__init__.py
@@ -611,15 +611,18 @@ class ModuleApi:
         localpart: str,
         displayname: Optional[str] = None,
         emails: Optional[List[str]] = None,
+        admin: bool = False,
     ) -> "defer.Deferred[str]":
         """Registers a new user with given localpart and optional displayname, emails.
 
         Added in Synapse v1.2.0.
+        Changed in Synapse v1.56.0: add 'admin' argument to register the user as admin.
 
         Args:
             localpart: The localpart of the new user.
             displayname: The displayname of the new user.
             emails: Emails to bind to the new user.
+            admin: True if the user should be registered as a server admin.
 
         Raises:
             SynapseError if there is an error performing the registration. Check the
@@ -633,6 +636,7 @@ class ModuleApi:
                 localpart=localpart,
                 default_display_name=displayname,
                 bind_emails=emails or [],
+                admin=admin,
             )
         )
 
diff --git a/synapse/res/templates/sso_auth_account_details.html b/synapse/res/templates/sso_auth_account_details.html
index b231aace01..1ba850369a 100644
--- a/synapse/res/templates/sso_auth_account_details.html
+++ b/synapse/res/templates/sso_auth_account_details.html
@@ -130,13 +130,13 @@
   </head>
   <body>
     <header>
-      <h1>Choose your account name</h1>
-      <p>This is required to create your account on {{ server_name }}, and you can't change this later.</p>
+      <h1>Create your account</h1>
+      <p>This is required. Continue to create your account on {{ server_name }}. You can't change this later.</p>
     </header>
     <main>
       <form method="post" class="form__input" id="form">
         <div class="username_input" id="username_input">
-          <label for="field-username">Username</label>
+          <label for="field-username">Username (required)</label>
           <div class="prefix">@</div>
           <input type="text" name="username" id="field-username" value="{{ user_attributes.localpart }}" autofocus>
           <div class="postfix">:{{ server_name }}</div>
@@ -145,7 +145,7 @@
         <input type="submit" value="Continue" class="primary-button">
         {% if user_attributes.avatar_url or user_attributes.display_name or user_attributes.emails %}
         <section class="idp-pick-details">
-          <h2>{% if idp.idp_icon %}<img src="{{ idp.idp_icon | mxc_to_http(24, 24) }}"/>{% endif %}Information from {{ idp.idp_name }}</h2>
+          <h2>{% if idp.idp_icon %}<img src="{{ idp.idp_icon | mxc_to_http(24, 24) }}"/>{% endif %}Optional data from {{ idp.idp_name }}</h2>
           {% if user_attributes.avatar_url %}
           <label class="idp-detail idp-avatar" for="idp-avatar">
             <div class="check-row">
diff --git a/synapse/res/templates/sso_auth_account_details.js b/synapse/res/templates/sso_auth_account_details.js
index 3c45df9078..82438519a2 100644
--- a/synapse/res/templates/sso_auth_account_details.js
+++ b/synapse/res/templates/sso_auth_account_details.js
@@ -62,7 +62,7 @@ function validateUsername(username) {
     usernameField.parentElement.classList.remove("invalid");
     usernameOutput.classList.remove("error");
     if (!username) {
-        return reportError("Please provide a username");
+        return reportError("This is required. Please provide a username");
     }
     if (username.length > 255) {
         return reportError("Too long, please choose something shorter");
diff --git a/synapse/res/templates/sso_footer.html b/synapse/res/templates/sso_footer.html
index 588a3d508d..b46e0d83fe 100644
--- a/synapse/res/templates/sso_footer.html
+++ b/synapse/res/templates/sso_footer.html
@@ -15,5 +15,5 @@
               </g>
           </g>
       </svg>
-      <p>An open network for secure, decentralized communication.<br>© 2021 The Matrix.org Foundation C.I.C.</p>
+      <p>An open network for secure, decentralized communication.<br>© 2022 The Matrix.org Foundation C.I.C.</p>
 </footer>
\ No newline at end of file
diff --git a/synapse/rest/__init__.py b/synapse/rest/__init__.py
index 762808a571..57c4773edc 100644
--- a/synapse/rest/__init__.py
+++ b/synapse/rest/__init__.py
@@ -32,6 +32,7 @@ from synapse.rest.client import (
     knock,
     login as v1_login,
     logout,
+    mutual_rooms,
     notifications,
     openid,
     password_policy,
@@ -49,7 +50,6 @@ from synapse.rest.client import (
     room_keys,
     room_upgrade_rest_servlet,
     sendtodevice,
-    shared_rooms,
     sync,
     tags,
     thirdparty,
@@ -132,4 +132,4 @@ class ClientRestResource(JsonResource):
         admin.register_servlets_for_client_rest_resource(hs, client_resource)
 
         # unstable
-        shared_rooms.register_servlets(hs, client_resource)
+        mutual_rooms.register_servlets(hs, client_resource)
diff --git a/synapse/rest/client/shared_rooms.py b/synapse/rest/client/mutual_rooms.py
index e669fa7890..27bfaf0b29 100644
--- a/synapse/rest/client/shared_rooms.py
+++ b/synapse/rest/client/mutual_rooms.py
@@ -28,13 +28,13 @@ if TYPE_CHECKING:
 logger = logging.getLogger(__name__)
 
 
-class UserSharedRoomsServlet(RestServlet):
+class UserMutualRoomsServlet(RestServlet):
     """
-    GET /uk.half-shot.msc2666/user/shared_rooms/{user_id} HTTP/1.1
+    GET /uk.half-shot.msc2666/user/mutual_rooms/{user_id} HTTP/1.1
     """
 
     PATTERNS = client_patterns(
-        "/uk.half-shot.msc2666/user/shared_rooms/(?P<user_id>[^/]*)",
+        "/uk.half-shot.msc2666/user/mutual_rooms/(?P<user_id>[^/]*)",
         releases=(),  # This is an unstable feature
     )
 
@@ -42,17 +42,19 @@ class UserSharedRoomsServlet(RestServlet):
         super().__init__()
         self.auth = hs.get_auth()
         self.store = hs.get_datastores().main
-        self.user_directory_active = hs.config.server.update_user_directory
+        self.user_directory_search_enabled = (
+            hs.config.userdirectory.user_directory_search_enabled
+        )
 
     async def on_GET(
         self, request: SynapseRequest, user_id: str
     ) -> Tuple[int, JsonDict]:
 
-        if not self.user_directory_active:
+        if not self.user_directory_search_enabled:
             raise SynapseError(
                 code=400,
-                msg="The user directory is disabled on this server. Cannot determine shared rooms.",
-                errcode=Codes.FORBIDDEN,
+                msg="User directory searching is disabled. Cannot determine shared rooms.",
+                errcode=Codes.UNKNOWN,
             )
 
         UserID.from_string(user_id)
@@ -64,7 +66,8 @@ class UserSharedRoomsServlet(RestServlet):
                 msg="You cannot request a list of shared rooms with yourself",
                 errcode=Codes.FORBIDDEN,
             )
-        rooms = await self.store.get_shared_rooms_for_users(
+
+        rooms = await self.store.get_mutual_rooms_for_users(
             requester.user.to_string(), user_id
         )
 
@@ -72,4 +75,4 @@ class UserSharedRoomsServlet(RestServlet):
 
 
 def register_servlets(hs: "HomeServer", http_server: HttpServer) -> None:
-    UserSharedRoomsServlet(hs).register(http_server)
+    UserMutualRoomsServlet(hs).register(http_server)
diff --git a/synapse/storage/database.py b/synapse/storage/database.py
index 9749f0c06e..367709a1a7 100644
--- a/synapse/storage/database.py
+++ b/synapse/storage/database.py
@@ -288,7 +288,7 @@ class LoggingTransaction:
         """
 
         if isinstance(self.database_engine, PostgresEngine):
-            from psycopg2.extras import execute_batch  # type: ignore
+            from psycopg2.extras import execute_batch
 
             self._do_execute(lambda *x: execute_batch(self.txn, *x), sql, args)
         else:
@@ -302,10 +302,18 @@ class LoggingTransaction:
         rows (e.g. INSERTs).
         """
         assert isinstance(self.database_engine, PostgresEngine)
-        from psycopg2.extras import execute_values  # type: ignore
+        from psycopg2.extras import execute_values
 
         return self._do_execute(
-            lambda *x: execute_values(self.txn, *x, fetch=fetch), sql, *args
+            # Type ignore: mypy is unhappy because if `x` is a 5-tuple, then there will
+            # be two values for `fetch`: one given positionally, and another given
+            # as a keyword argument. We might be able to fix this by
+            # - propagating the signature of psycopg2.extras.execute_values to this
+            #   function, or
+            # - changing `*args: Any` to `values: T` for some appropriate T.
+            lambda *x: execute_values(self.txn, *x, fetch=fetch),  # type: ignore[misc]
+            sql,
+            *args,
         )
 
     def execute(self, sql: str, *args: Any) -> None:
diff --git a/synapse/storage/databases/main/user_directory.py b/synapse/storage/databases/main/user_directory.py
index 55cc9178f0..0595df01d3 100644
--- a/synapse/storage/databases/main/user_directory.py
+++ b/synapse/storage/databases/main/user_directory.py
@@ -730,7 +730,7 @@ class UserDirectoryStore(UserDirectoryBackgroundUpdateStore):
         users.update(rows)
         return list(users)
 
-    async def get_shared_rooms_for_users(
+    async def get_mutual_rooms_for_users(
         self, user_id: str, other_user_id: str
     ) -> Set[str]:
         """
@@ -744,7 +744,7 @@ class UserDirectoryStore(UserDirectoryBackgroundUpdateStore):
             A set of room ID's that the users share.
         """
 
-        def _get_shared_rooms_for_users_txn(
+        def _get_mutual_rooms_for_users_txn(
             txn: LoggingTransaction,
         ) -> List[Dict[str, str]]:
             txn.execute(
@@ -768,7 +768,7 @@ class UserDirectoryStore(UserDirectoryBackgroundUpdateStore):
             return rows
 
         rows = await self.db_pool.runInteraction(
-            "get_shared_rooms_for_users", _get_shared_rooms_for_users_txn
+            "get_mutual_rooms_for_users", _get_mutual_rooms_for_users_txn
         )
 
         return {row["room_id"] for row in rows}
diff --git a/synapse/storage/engines/__init__.py b/synapse/storage/engines/__init__.py
index 9abc02046e..afb7d5054d 100644
--- a/synapse/storage/engines/__init__.py
+++ b/synapse/storage/engines/__init__.py
@@ -27,7 +27,7 @@ def create_engine(database_config) -> BaseDatabaseEngine:
 
     if name == "psycopg2":
         # Note that psycopg2cffi-compat provides the psycopg2 module on pypy.
-        import psycopg2  # type: ignore
+        import psycopg2
 
         return PostgresEngine(psycopg2, database_config)
 
diff --git a/synapse/storage/engines/postgres.py b/synapse/storage/engines/postgres.py
index 808342fafb..e8d29e2870 100644
--- a/synapse/storage/engines/postgres.py
+++ b/synapse/storage/engines/postgres.py
@@ -47,17 +47,26 @@ class PostgresEngine(BaseDatabaseEngine):
         self.default_isolation_level = (
             self.module.extensions.ISOLATION_LEVEL_REPEATABLE_READ
         )
+        self.config = database_config
 
     @property
     def single_threaded(self) -> bool:
         return False
 
+    def get_db_locale(self, txn):
+        txn.execute(
+            "SELECT datcollate, datctype FROM pg_database WHERE datname = current_database()"
+        )
+        collation, ctype = txn.fetchone()
+        return collation, ctype
+
     def check_database(self, db_conn, allow_outdated_version: bool = False):
         # Get the version of PostgreSQL that we're using. As per the psycopg2
         # docs: The number is formed by converting the major, minor, and
         # revision numbers into two-decimal-digit numbers and appending them
         # together. For example, version 8.1.5 will be returned as 80105
         self._version = db_conn.server_version
+        allow_unsafe_locale = self.config.get("allow_unsafe_locale", False)
 
         # Are we on a supported PostgreSQL version?
         if not allow_outdated_version and self._version < 100000:
@@ -72,33 +81,39 @@ class PostgresEngine(BaseDatabaseEngine):
                     "See docs/postgres.md for more information." % (rows[0][0],)
                 )
 
-            txn.execute(
-                "SELECT datcollate, datctype FROM pg_database WHERE datname = current_database()"
-            )
-            collation, ctype = txn.fetchone()
+            collation, ctype = self.get_db_locale(txn)
             if collation != "C":
                 logger.warning(
-                    "Database has incorrect collation of %r. Should be 'C'\n"
-                    "See docs/postgres.md for more information.",
+                    "Database has incorrect collation of %r. Should be 'C'",
                     collation,
                 )
+                if not allow_unsafe_locale:
+                    raise IncorrectDatabaseSetup(
+                        "Database has incorrect collation of %r. Should be 'C'\n"
+                        "See docs/postgres.md for more information. You can override this check by"
+                        "setting 'allow_unsafe_locale' to true in the database config.",
+                        collation,
+                    )
 
             if ctype != "C":
-                logger.warning(
-                    "Database has incorrect ctype of %r. Should be 'C'\n"
-                    "See docs/postgres.md for more information.",
-                    ctype,
-                )
+                if not allow_unsafe_locale:
+                    logger.warning(
+                        "Database has incorrect ctype of %r. Should be 'C'",
+                        ctype,
+                    )
+                    raise IncorrectDatabaseSetup(
+                        "Database has incorrect ctype of %r. Should be 'C'\n"
+                        "See docs/postgres.md for more information. You can override this check by"
+                        "setting 'allow_unsafe_locale' to true in the database config.",
+                        ctype,
+                    )
 
     def check_new_database(self, txn):
         """Gets called when setting up a brand new database. This allows us to
         apply stricter checks on new databases versus existing database.
         """
 
-        txn.execute(
-            "SELECT datcollate, datctype FROM pg_database WHERE datname = current_database()"
-        )
-        collation, ctype = txn.fetchone()
+        collation, ctype = self.get_db_locale(txn)
 
         errors = []
 
diff --git a/tests/module_api/test_api.py b/tests/module_api/test_api.py
index c3f20f9692..10dd94b549 100644
--- a/tests/module_api/test_api.py
+++ b/tests/module_api/test_api.py
@@ -86,6 +86,16 @@ class ModuleApiTestCase(HomeserverTestCase):
         displayname = self.get_success(self.store.get_profile_displayname("bob"))
         self.assertEqual(displayname, "Bobberino")
 
+    def test_can_register_admin_user(self):
+        user_id = self.get_success(
+            self.register_user(
+                "bob_module_admin", "1234", displayname="Bobberino Admin", admin=True
+            )
+        )
+        found_user = self.get_success(self.module_api.get_userinfo_by_id(user_id))
+        self.assertEqual(found_user.user_id.to_string(), user_id)
+        self.assertIdentical(found_user.is_admin, True)
+
     def test_get_userinfo_by_id(self):
         user_id = self.register_user("alice", "1234")
         found_user = self.get_success(self.module_api.get_userinfo_by_id(user_id))
diff --git a/tests/rest/client/test_account.py b/tests/rest/client/test_account.py
index def836054d..27946febff 100644
--- a/tests/rest/client/test_account.py
+++ b/tests/rest/client/test_account.py
@@ -31,7 +31,7 @@ from synapse.rest import admin
 from synapse.rest.client import account, login, register, room
 from synapse.rest.synapse.client.password_reset import PasswordResetSubmitTokenResource
 from synapse.server import HomeServer
-from synapse.types import JsonDict
+from synapse.types import JsonDict, UserID
 from synapse.util import Clock
 
 from tests import unittest
@@ -1222,6 +1222,62 @@ class AccountStatusTestCase(unittest.HomeserverTestCase):
             expected_failures=[users[2]],
         )
 
+    @unittest.override_config(
+        {
+            "use_account_validity_in_account_status": True,
+        }
+    )
+    def test_no_account_validity(self) -> None:
+        """Tests that if we decide to include account validity in the response but no
+        account validity 'is_user_expired' callback is provided, we default to marking all
+        users as not expired.
+        """
+        user = self.register_user("someuser", "password")
+
+        self._test_status(
+            users=[user],
+            expected_statuses={
+                user: {
+                    "exists": True,
+                    "deactivated": False,
+                    "org.matrix.expired": False,
+                },
+            },
+            expected_failures=[],
+        )
+
+    @unittest.override_config(
+        {
+            "use_account_validity_in_account_status": True,
+        }
+    )
+    def test_account_validity_expired(self) -> None:
+        """Test that if we decide to include account validity in the response and the user
+        is expired, we return the correct info.
+        """
+        user = self.register_user("someuser", "password")
+
+        async def is_expired(user_id: str) -> bool:
+            # We can't blindly say everyone is expired, otherwise the request to get the
+            # account status will fail.
+            return UserID.from_string(user_id).localpart == "someuser"
+
+        self.hs.get_account_validity_handler()._is_user_expired_callbacks.append(
+            is_expired
+        )
+
+        self._test_status(
+            users=[user],
+            expected_statuses={
+                user: {
+                    "exists": True,
+                    "deactivated": False,
+                    "org.matrix.expired": True,
+                },
+            },
+            expected_failures=[],
+        )
+
     def _test_status(
         self,
         users: Optional[List[str]],
diff --git a/tests/rest/client/test_shared_rooms.py b/tests/rest/client/test_mutual_rooms.py
index 3818b7b14b..7b7d283bb6 100644
--- a/tests/rest/client/test_shared_rooms.py
+++ b/tests/rest/client/test_mutual_rooms.py
@@ -14,7 +14,7 @@
 from twisted.test.proto_helpers import MemoryReactor
 
 import synapse.rest.admin
-from synapse.rest.client import login, room, shared_rooms
+from synapse.rest.client import login, mutual_rooms, room
 from synapse.server import HomeServer
 from synapse.util import Clock
 
@@ -22,16 +22,16 @@ from tests import unittest
 from tests.server import FakeChannel
 
 
-class UserSharedRoomsTest(unittest.HomeserverTestCase):
+class UserMutualRoomsTest(unittest.HomeserverTestCase):
     """
-    Tests the UserSharedRoomsServlet.
+    Tests the UserMutualRoomsServlet.
     """
 
     servlets = [
         login.register_servlets,
         synapse.rest.admin.register_servlets_for_client_rest_resource,
         room.register_servlets,
-        shared_rooms.register_servlets,
+        mutual_rooms.register_servlets,
     ]
 
     def make_homeserver(self, reactor: MemoryReactor, clock: Clock) -> HomeServer:
@@ -43,10 +43,10 @@ class UserSharedRoomsTest(unittest.HomeserverTestCase):
         self.store = hs.get_datastores().main
         self.handler = hs.get_user_directory_handler()
 
-    def _get_shared_rooms(self, token: str, other_user: str) -> FakeChannel:
+    def _get_mutual_rooms(self, token: str, other_user: str) -> FakeChannel:
         return self.make_request(
             "GET",
-            "/_matrix/client/unstable/uk.half-shot.msc2666/user/shared_rooms/%s"
+            "/_matrix/client/unstable/uk.half-shot.msc2666/user/mutual_rooms/%s"
             % other_user,
             access_token=token,
         )
@@ -56,14 +56,14 @@ class UserSharedRoomsTest(unittest.HomeserverTestCase):
         A room should show up in the shared list of rooms between two users
         if it is public.
         """
-        self._check_shared_rooms_with(room_one_is_public=True, room_two_is_public=True)
+        self._check_mutual_rooms_with(room_one_is_public=True, room_two_is_public=True)
 
     def test_shared_room_list_private(self) -> None:
         """
         A room should show up in the shared list of rooms between two users
         if it is private.
         """
-        self._check_shared_rooms_with(
+        self._check_mutual_rooms_with(
             room_one_is_public=False, room_two_is_public=False
         )
 
@@ -72,9 +72,9 @@ class UserSharedRoomsTest(unittest.HomeserverTestCase):
         The shared room list between two users should contain both public and private
         rooms.
         """
-        self._check_shared_rooms_with(room_one_is_public=True, room_two_is_public=False)
+        self._check_mutual_rooms_with(room_one_is_public=True, room_two_is_public=False)
 
-    def _check_shared_rooms_with(
+    def _check_mutual_rooms_with(
         self, room_one_is_public: bool, room_two_is_public: bool
     ) -> None:
         """Checks that shared public or private rooms between two users appear in
@@ -94,7 +94,7 @@ class UserSharedRoomsTest(unittest.HomeserverTestCase):
 
         # Check shared rooms from user1's perspective.
         # We should see the one room in common
-        channel = self._get_shared_rooms(u1_token, u2)
+        channel = self._get_mutual_rooms(u1_token, u2)
         self.assertEqual(200, channel.code, channel.result)
         self.assertEqual(len(channel.json_body["joined"]), 1)
         self.assertEqual(channel.json_body["joined"][0], room_id_one)
@@ -107,7 +107,7 @@ class UserSharedRoomsTest(unittest.HomeserverTestCase):
         self.helper.join(room_id_two, user=u2, tok=u2_token)
 
         # Check shared rooms again. We should now see both rooms.
-        channel = self._get_shared_rooms(u1_token, u2)
+        channel = self._get_mutual_rooms(u1_token, u2)
         self.assertEqual(200, channel.code, channel.result)
         self.assertEqual(len(channel.json_body["joined"]), 2)
         for room_id_id in channel.json_body["joined"]:
@@ -128,7 +128,7 @@ class UserSharedRoomsTest(unittest.HomeserverTestCase):
         self.helper.join(room, user=u2, tok=u2_token)
 
         # Assert user directory is not empty
-        channel = self._get_shared_rooms(u1_token, u2)
+        channel = self._get_mutual_rooms(u1_token, u2)
         self.assertEqual(200, channel.code, channel.result)
         self.assertEqual(len(channel.json_body["joined"]), 1)
         self.assertEqual(channel.json_body["joined"][0], room)
@@ -136,11 +136,11 @@ class UserSharedRoomsTest(unittest.HomeserverTestCase):
         self.helper.leave(room, user=u1, tok=u1_token)
 
         # Check user1's view of shared rooms with user2
-        channel = self._get_shared_rooms(u1_token, u2)
+        channel = self._get_mutual_rooms(u1_token, u2)
         self.assertEqual(200, channel.code, channel.result)
         self.assertEqual(len(channel.json_body["joined"]), 0)
 
         # Check user2's view of shared rooms with user1
-        channel = self._get_shared_rooms(u2_token, u1)
+        channel = self._get_mutual_rooms(u2_token, u1)
         self.assertEqual(200, channel.code, channel.result)
         self.assertEqual(len(channel.json_body["joined"]), 0)
diff --git a/tests/storage/test_unsafe_locale.py b/tests/storage/test_unsafe_locale.py
new file mode 100644
index 0000000000..ba53c22818
--- /dev/null
+++ b/tests/storage/test_unsafe_locale.py
@@ -0,0 +1,46 @@
+# Copyright 2022 The Matrix.org Foundation C.I.C.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+from unittest.mock import MagicMock, patch
+
+from synapse.storage.database import make_conn
+from synapse.storage.engines._base import IncorrectDatabaseSetup
+
+from tests.unittest import HomeserverTestCase
+from tests.utils import USE_POSTGRES_FOR_TESTS
+
+
+class UnsafeLocaleTest(HomeserverTestCase):
+    if not USE_POSTGRES_FOR_TESTS:
+        skip = "Requires Postgres"
+
+    @patch("synapse.storage.engines.postgres.PostgresEngine.get_db_locale")
+    def test_unsafe_locale(self, mock_db_locale: MagicMock) -> None:
+        mock_db_locale.return_value = ("B", "B")
+        database = self.hs.get_datastores().databases[0]
+
+        db_conn = make_conn(database._database_config, database.engine, "test_unsafe")
+        with self.assertRaises(IncorrectDatabaseSetup):
+            database.engine.check_database(db_conn)
+        with self.assertRaises(IncorrectDatabaseSetup):
+            database.engine.check_new_database(db_conn)
+        db_conn.close()
+
+    def test_safe_locale(self) -> None:
+        database = self.hs.get_datastores().databases[0]
+
+        db_conn = make_conn(database._database_config, database.engine, "test_unsafe")
+        with db_conn.cursor() as txn:
+            res = database.engine.get_db_locale(txn)
+        self.assertEqual(res, ("C", "C"))
+        db_conn.close()