Use direct references for some configuration variables (part 3) (#10885)

This avoids the overhead of searching through the various
configuration classes by directly referencing the class that
the attributes are in.

It also improves type hints since mypy can now resolve the
types of the configuration variables.

32 files changed, 137 insertions, 119 deletions

diff --git a/changelog.d/10885.misc b/changelog.d/10885.misc
new file mode 100644
index 0000000000..586a0b3a96
--- /dev/null
+++ b/changelog.d/10885.misc
@@ -0,0 +1 @@
+Use direct references to config flags.
diff --git a/synapse/app/homeserver.py b/synapse/app/homeserver.py
index b909f8db8d..886e291e4c 100644
--- a/synapse/app/homeserver.py
+++ b/synapse/app/homeserver.py
@@ -195,7 +195,7 @@ class SynapseHomeServer(HomeServer):
                 }
             )
 
-            if self.config.threepid_behaviour_email == ThreepidBehaviour.LOCAL:
+            if self.config.email.threepid_behaviour_email == ThreepidBehaviour.LOCAL:
                 from synapse.rest.synapse.client.password_reset import (
                     PasswordResetSubmitTokenResource,
                 )
diff --git a/synapse/config/consent.py b/synapse/config/consent.py
index b05a9bd97f..ecc43b08b9 100644
--- a/synapse/config/consent.py
+++ b/synapse/config/consent.py
@@ -13,6 +13,7 @@
 # limitations under the License.
 
 from os import path
+from typing import Optional
 
 from synapse.config import ConfigError
 
@@ -78,8 +79,8 @@ class ConsentConfig(Config):
     def __init__(self, *args):
         super().__init__(*args)
 
-        self.user_consent_version = None
-        self.user_consent_template_dir = None
+        self.user_consent_version: Optional[str] = None
+        self.user_consent_template_dir: Optional[str] = None
         self.user_consent_server_notice_content = None
         self.user_consent_server_notice_to_guests = False
         self.block_events_without_consent_error = None
@@ -94,7 +95,9 @@ class ConsentConfig(Config):
             return
         self.user_consent_version = str(consent_config["version"])
         self.user_consent_template_dir = self.abspath(consent_config["template_dir"])
-        if not path.isdir(self.user_consent_template_dir):
+        if not isinstance(self.user_consent_template_dir, str) or not path.isdir(
+            self.user_consent_template_dir
+        ):
             raise ConfigError(
                 "Could not find template directory '%s'"
                 % (self.user_consent_template_dir,)
diff --git a/synapse/handlers/account_validity.py b/synapse/handlers/account_validity.py
index 4724565ba5..5a5f124ddf 100644
--- a/synapse/handlers/account_validity.py
+++ b/synapse/handlers/account_validity.py
@@ -47,7 +47,7 @@ class AccountValidityHandler:
         self.send_email_handler = self.hs.get_send_email_handler()
         self.clock = self.hs.get_clock()
 
-        self._app_name = self.hs.config.email_app_name
+        self._app_name = self.hs.config.email.email_app_name
 
         self._account_validity_enabled = (
             hs.config.account_validity.account_validity_enabled
diff --git a/synapse/handlers/appservice.py b/synapse/handlers/appservice.py
index b7213b67a5..163278708c 100644
--- a/synapse/handlers/appservice.py
+++ b/synapse/handlers/appservice.py
@@ -52,7 +52,7 @@ class ApplicationServicesHandler:
         self.scheduler = hs.get_application_service_scheduler()
         self.started_scheduler = False
         self.clock = hs.get_clock()
-        self.notify_appservices = hs.config.notify_appservices
+        self.notify_appservices = hs.config.appservice.notify_appservices
         self.event_sources = hs.get_event_sources()
 
         self.current_max = 0
diff --git a/synapse/handlers/auth.py b/synapse/handlers/auth.py
index bcd4249e09..b747f80bc1 100644
--- a/synapse/handlers/auth.py
+++ b/synapse/handlers/auth.py
@@ -210,15 +210,15 @@ class AuthHandler(BaseHandler):
 
         self.password_providers = [
             PasswordProvider.load(module, config, account_handler)
-            for module, config in hs.config.password_providers
+            for module, config in hs.config.authproviders.password_providers
         ]
 
         logger.info("Extra password_providers: %s", self.password_providers)
 
         self.hs = hs  # FIXME better possibility to access registrationHandler later?
         self.macaroon_gen = hs.get_macaroon_generator()
-        self._password_enabled = hs.config.password_enabled
-        self._password_localdb_enabled = hs.config.password_localdb_enabled
+        self._password_enabled = hs.config.auth.password_enabled
+        self._password_localdb_enabled = hs.config.auth.password_localdb_enabled
 
         # start out by assuming PASSWORD is enabled; we will remove it later if not.
         login_types = set()
@@ -250,7 +250,7 @@ class AuthHandler(BaseHandler):
         )
 
         # The number of seconds to keep a UI auth session active.
-        self._ui_auth_session_timeout = hs.config.ui_auth_session_timeout
+        self._ui_auth_session_timeout = hs.config.auth.ui_auth_session_timeout
 
         # Ratelimitier for failed /login attempts
         self._failed_login_attempts_ratelimiter = Ratelimiter(
@@ -739,19 +739,19 @@ class AuthHandler(BaseHandler):
         return canonical_id
 
     def _get_params_recaptcha(self) -> dict:
-        return {"public_key": self.hs.config.recaptcha_public_key}
+        return {"public_key": self.hs.config.captcha.recaptcha_public_key}
 
     def _get_params_terms(self) -> dict:
         return {
             "policies": {
                 "privacy_policy": {
-                    "version": self.hs.config.user_consent_version,
+                    "version": self.hs.config.consent.user_consent_version,
                     "en": {
-                        "name": self.hs.config.user_consent_policy_name,
+                        "name": self.hs.config.consent.user_consent_policy_name,
                         "url": "%s_matrix/consent?v=%s"
                         % (
                             self.hs.config.server.public_baseurl,
-                            self.hs.config.user_consent_version,
+                            self.hs.config.consent.user_consent_version,
                         ),
                     },
                 }
@@ -1016,7 +1016,7 @@ class AuthHandler(BaseHandler):
     def can_change_password(self) -> bool:
         """Get whether users on this server are allowed to change or set a password.
 
-        Both `config.password_enabled` and `config.password_localdb_enabled` must be true.
+        Both `config.auth.password_enabled` and `config.auth.password_localdb_enabled` must be true.
 
         Note that any account (even SSO accounts) are allowed to add passwords if the above
         is true.
@@ -1486,7 +1486,7 @@ class AuthHandler(BaseHandler):
             pw = unicodedata.normalize("NFKC", password)
 
             return bcrypt.hashpw(
-                pw.encode("utf8") + self.hs.config.password_pepper.encode("utf8"),
+                pw.encode("utf8") + self.hs.config.auth.password_pepper.encode("utf8"),
                 bcrypt.gensalt(self.bcrypt_rounds),
             ).decode("ascii")
 
@@ -1510,7 +1510,7 @@ class AuthHandler(BaseHandler):
             pw = unicodedata.normalize("NFKC", password)
 
             return bcrypt.checkpw(
-                pw.encode("utf8") + self.hs.config.password_pepper.encode("utf8"),
+                pw.encode("utf8") + self.hs.config.auth.password_pepper.encode("utf8"),
                 checked_hash,
             )
 
diff --git a/synapse/handlers/cas.py b/synapse/handlers/cas.py
index b0b188dc78..5d8f6c50a9 100644
--- a/synapse/handlers/cas.py
+++ b/synapse/handlers/cas.py
@@ -65,10 +65,10 @@ class CasHandler:
         self._auth_handler = hs.get_auth_handler()
         self._registration_handler = hs.get_registration_handler()
 
-        self._cas_server_url = hs.config.cas_server_url
-        self._cas_service_url = hs.config.cas_service_url
-        self._cas_displayname_attribute = hs.config.cas_displayname_attribute
-        self._cas_required_attributes = hs.config.cas_required_attributes
+        self._cas_server_url = hs.config.cas.cas_server_url
+        self._cas_service_url = hs.config.cas.cas_service_url
+        self._cas_displayname_attribute = hs.config.cas.cas_displayname_attribute
+        self._cas_required_attributes = hs.config.cas.cas_required_attributes
 
         self._http_client = hs.get_proxied_http_client()
 
diff --git a/synapse/handlers/identity.py b/synapse/handlers/identity.py
index 8b8f1f41ca..fe8a995892 100644
--- a/synapse/handlers/identity.py
+++ b/synapse/handlers/identity.py
@@ -62,7 +62,7 @@ class IdentityHandler(BaseHandler):
         self.federation_http_client = hs.get_federation_http_client()
         self.hs = hs
 
-        self._web_client_location = hs.config.invite_client_location
+        self._web_client_location = hs.config.email.invite_client_location
 
         # Ratelimiters for `/requestToken` endpoints.
         self._3pid_validation_ratelimiter_ip = Ratelimiter(
@@ -419,7 +419,7 @@ class IdentityHandler(BaseHandler):
 
         token_expires = (
             self.hs.get_clock().time_msec()
-            + self.hs.config.email_validation_token_lifetime
+            + self.hs.config.email.email_validation_token_lifetime
         )
 
         await self.store.start_or_continue_validation_session(
@@ -465,7 +465,7 @@ class IdentityHandler(BaseHandler):
         if next_link:
             params["next_link"] = next_link
 
-        if self.hs.config.using_identity_server_from_trusted_list:
+        if self.hs.config.email.using_identity_server_from_trusted_list:
             # Warn that a deprecated config option is in use
             logger.warning(
                 'The config option "trust_identity_server_for_password_resets" '
@@ -518,7 +518,7 @@ class IdentityHandler(BaseHandler):
         if next_link:
             params["next_link"] = next_link
 
-        if self.hs.config.using_identity_server_from_trusted_list:
+        if self.hs.config.email.using_identity_server_from_trusted_list:
             # Warn that a deprecated config option is in use
             logger.warning(
                 'The config option "trust_identity_server_for_password_resets" '
@@ -572,12 +572,12 @@ class IdentityHandler(BaseHandler):
         validation_session = None
 
         # Try to validate as email
-        if self.hs.config.threepid_behaviour_email == ThreepidBehaviour.REMOTE:
+        if self.hs.config.email.threepid_behaviour_email == ThreepidBehaviour.REMOTE:
             # Ask our delegated email identity server
             validation_session = await self.threepid_from_creds(
                 self.hs.config.account_threepid_delegate_email, threepid_creds
             )
-        elif self.hs.config.threepid_behaviour_email == ThreepidBehaviour.LOCAL:
+        elif self.hs.config.email.threepid_behaviour_email == ThreepidBehaviour.LOCAL:
             # Get a validated session matching these details
             validation_session = await self.store.get_threepid_validation_session(
                 "email", client_secret, sid=sid, validated=True
diff --git a/synapse/handlers/message.py b/synapse/handlers/message.py
index 7a5d8e6f4e..ad4e4a3d6f 100644
--- a/synapse/handlers/message.py
+++ b/synapse/handlers/message.py
@@ -443,7 +443,7 @@ class EventCreationHandler:
         )
 
         self._block_events_without_consent_error = (
-            self.config.block_events_without_consent_error
+            self.config.consent.block_events_without_consent_error
         )
 
         # we need to construct a ConsentURIBuilder here, as it checks that the necessary
@@ -744,7 +744,7 @@ class EventCreationHandler:
         if u["appservice_id"] is not None:
             # users registered by an appservice are exempt
             return
-        if u["consent_version"] == self.config.user_consent_version:
+        if u["consent_version"] == self.config.consent.user_consent_version:
             return
 
         consent_uri = self._consent_uri_builder.build_user_consent_uri(user.localpart)
diff --git a/synapse/handlers/password_policy.py b/synapse/handlers/password_policy.py
index cd21efdcc6..eadd7ced09 100644
--- a/synapse/handlers/password_policy.py
+++ b/synapse/handlers/password_policy.py
@@ -27,8 +27,8 @@ logger = logging.getLogger(__name__)
 
 class PasswordPolicyHandler:
     def __init__(self, hs: "HomeServer"):
-        self.policy = hs.config.password_policy
-        self.enabled = hs.config.password_policy_enabled
+        self.policy = hs.config.auth.password_policy
+        self.enabled = hs.config.auth.password_policy_enabled
 
         # Regexps for the spec'd policy parameters.
         self.regexp_digit = re.compile("[0-9]")
diff --git a/synapse/handlers/register.py b/synapse/handlers/register.py
index 1c195c65db..01c5e1385d 100644
--- a/synapse/handlers/register.py
+++ b/synapse/handlers/register.py
@@ -97,6 +97,7 @@ class RegistrationHandler(BaseHandler):
         self.ratelimiter = hs.get_registration_ratelimiter()
         self.macaroon_gen = hs.get_macaroon_generator()
         self._account_validity_handler = hs.get_account_validity_handler()
+        self._user_consent_version = self.hs.config.consent.user_consent_version
         self._server_notices_mxid = hs.config.server_notices_mxid
         self._server_name = hs.hostname
 
@@ -339,7 +340,7 @@ class RegistrationHandler(BaseHandler):
             auth_provider=(auth_provider_id or ""),
         ).inc()
 
-        if not self.hs.config.user_consent_at_registration:
+        if not self.hs.config.consent.user_consent_at_registration:
             if not self.hs.config.auto_join_rooms_for_guests and make_guest:
                 logger.info(
                     "Skipping auto-join for %s because auto-join for guests is disabled",
@@ -864,7 +865,9 @@ class RegistrationHandler(BaseHandler):
             await self._register_msisdn_threepid(user_id, threepid)
 
         if auth_result and LoginType.TERMS in auth_result:
-            await self._on_user_consented(user_id, self.hs.config.user_consent_version)
+            # The terms type should only exist if consent is enabled.
+            assert self._user_consent_version is not None
+            await self._on_user_consented(user_id, self._user_consent_version)
 
     async def _on_user_consented(self, user_id: str, consent_version: str) -> None:
         """A user consented to the terms on registration
@@ -910,8 +913,8 @@ class RegistrationHandler(BaseHandler):
         # getting mail spam where they weren't before if email
         # notifs are set up on a homeserver)
         if (
-            self.hs.config.email_enable_notifs
-            and self.hs.config.email_notif_for_new_users
+            self.hs.config.email.email_enable_notifs
+            and self.hs.config.email.email_notif_for_new_users
             and token
         ):
             # Pull the ID of the access token back out of the db
diff --git a/synapse/handlers/ui_auth/checkers.py b/synapse/handlers/ui_auth/checkers.py
index ea9325e96a..8f5d465fa1 100644
--- a/synapse/handlers/ui_auth/checkers.py
+++ b/synapse/handlers/ui_auth/checkers.py
@@ -82,10 +82,10 @@ class RecaptchaAuthChecker(UserInteractiveAuthChecker):
 
     def __init__(self, hs: "HomeServer"):
         super().__init__(hs)
-        self._enabled = bool(hs.config.recaptcha_private_key)
+        self._enabled = bool(hs.config.captcha.recaptcha_private_key)
         self._http_client = hs.get_proxied_http_client()
-        self._url = hs.config.recaptcha_siteverify_api
-        self._secret = hs.config.recaptcha_private_key
+        self._url = hs.config.captcha.recaptcha_siteverify_api
+        self._secret = hs.config.captcha.recaptcha_private_key
 
     def is_enabled(self) -> bool:
         return self._enabled
@@ -161,12 +161,17 @@ class _BaseThreepidAuthChecker:
                 self.hs.config.account_threepid_delegate_msisdn, threepid_creds
             )
         elif medium == "email":
-            if self.hs.config.threepid_behaviour_email == ThreepidBehaviour.REMOTE:
+            if (
+                self.hs.config.email.threepid_behaviour_email
+                == ThreepidBehaviour.REMOTE
+            ):
                 assert self.hs.config.account_threepid_delegate_email
                 threepid = await identity_handler.threepid_from_creds(
                     self.hs.config.account_threepid_delegate_email, threepid_creds
                 )
-            elif self.hs.config.threepid_behaviour_email == ThreepidBehaviour.LOCAL:
+            elif (
+                self.hs.config.email.threepid_behaviour_email == ThreepidBehaviour.LOCAL
+            ):
                 threepid = None
                 row = await self.store.get_threepid_validation_session(
                     medium,
@@ -218,7 +223,7 @@ class EmailIdentityAuthChecker(UserInteractiveAuthChecker, _BaseThreepidAuthChec
         _BaseThreepidAuthChecker.__init__(self, hs)
 
     def is_enabled(self) -> bool:
-        return self.hs.config.threepid_behaviour_email in (
+        return self.hs.config.email.threepid_behaviour_email in (
             ThreepidBehaviour.REMOTE,
             ThreepidBehaviour.LOCAL,
         )
diff --git a/synapse/module_api/__init__.py b/synapse/module_api/__init__.py
index 174e6934a8..8ae21bc43c 100644
--- a/synapse/module_api/__init__.py
+++ b/synapse/module_api/__init__.py
@@ -119,14 +119,16 @@ class ModuleApi:
         self.custom_template_dir = hs.config.server.custom_template_directory
 
         try:
-            app_name = self._hs.config.email_app_name
+            app_name = self._hs.config.email.email_app_name
 
-            self._from_string = self._hs.config.email_notif_from % {"app": app_name}
+            self._from_string = self._hs.config.email.email_notif_from % {
+                "app": app_name
+            }
         except (KeyError, TypeError):
             # If substitution failed (which can happen if the string contains
             # placeholders other than just "app", or if the type of the placeholder is
             # not a string), fall back to the bare strings.
-            self._from_string = self._hs.config.email_notif_from
+            self._from_string = self._hs.config.email.email_notif_from
 
         self._raw_from = email.utils.parseaddr(self._from_string)[1]
 
diff --git a/synapse/push/pusher.py b/synapse/push/pusher.py
index 29ed346d37..b57e094091 100644
--- a/synapse/push/pusher.py
+++ b/synapse/push/pusher.py
@@ -77,4 +77,4 @@ class PusherFactory:
             if isinstance(brand, str):
                 return brand
 
-        return self.config.email_app_name
+        return self.config.email.email_app_name
diff --git a/synapse/rest/admin/users.py b/synapse/rest/admin/users.py
index 681e491826..46bfec4623 100644
--- a/synapse/rest/admin/users.py
+++ b/synapse/rest/admin/users.py
@@ -368,8 +368,8 @@ class UserRestServletV2(RestServlet):
                         user_id, medium, address, current_time
                     )
                     if (
-                        self.hs.config.email_enable_notifs
-                        and self.hs.config.email_notif_for_new_users
+                        self.hs.config.email.email_enable_notifs
+                        and self.hs.config.email.email_notif_for_new_users
                     ):
                         await self.pusher_pool.add_pusher(
                             user_id=user_id,
diff --git a/synapse/rest/client/account.py b/synapse/rest/client/account.py
index aefaaa8ae8..6a7608d60b 100644
--- a/synapse/rest/client/account.py
+++ b/synapse/rest/client/account.py
@@ -64,17 +64,17 @@ class EmailPasswordRequestTokenRestServlet(RestServlet):
         self.config = hs.config
         self.identity_handler = hs.get_identity_handler()
 
-        if self.config.threepid_behaviour_email == ThreepidBehaviour.LOCAL:
+        if self.config.email.threepid_behaviour_email == ThreepidBehaviour.LOCAL:
             self.mailer = Mailer(
                 hs=self.hs,
-                app_name=self.config.email_app_name,
-                template_html=self.config.email_password_reset_template_html,
-                template_text=self.config.email_password_reset_template_text,
+                app_name=self.config.email.email_app_name,
+                template_html=self.config.email.email_password_reset_template_html,
+                template_text=self.config.email.email_password_reset_template_text,
             )
 
     async def on_POST(self, request: SynapseRequest) -> Tuple[int, JsonDict]:
-        if self.config.threepid_behaviour_email == ThreepidBehaviour.OFF:
-            if self.config.local_threepid_handling_disabled_due_to_email_config:
+        if self.config.email.threepid_behaviour_email == ThreepidBehaviour.OFF:
+            if self.config.email.local_threepid_handling_disabled_due_to_email_config:
                 logger.warning(
                     "User password resets have been disabled due to lack of email config"
                 )
@@ -129,7 +129,7 @@ class EmailPasswordRequestTokenRestServlet(RestServlet):
 
             raise SynapseError(400, "Email not found", Codes.THREEPID_NOT_FOUND)
 
-        if self.config.threepid_behaviour_email == ThreepidBehaviour.REMOTE:
+        if self.config.email.threepid_behaviour_email == ThreepidBehaviour.REMOTE:
             assert self.hs.config.account_threepid_delegate_email
 
             # Have the configured identity server handle the request
@@ -349,17 +349,17 @@ class EmailThreepidRequestTokenRestServlet(RestServlet):
         self.identity_handler = hs.get_identity_handler()
         self.store = self.hs.get_datastore()
 
-        if self.config.threepid_behaviour_email == ThreepidBehaviour.LOCAL:
+        if self.config.email.threepid_behaviour_email == ThreepidBehaviour.LOCAL:
             self.mailer = Mailer(
                 hs=self.hs,
-                app_name=self.config.email_app_name,
-                template_html=self.config.email_add_threepid_template_html,
-                template_text=self.config.email_add_threepid_template_text,
+                app_name=self.config.email.email_app_name,
+                template_html=self.config.email.email_add_threepid_template_html,
+                template_text=self.config.email.email_add_threepid_template_text,
             )
 
     async def on_POST(self, request: SynapseRequest) -> Tuple[int, JsonDict]:
-        if self.config.threepid_behaviour_email == ThreepidBehaviour.OFF:
-            if self.config.local_threepid_handling_disabled_due_to_email_config:
+        if self.config.email.threepid_behaviour_email == ThreepidBehaviour.OFF:
+            if self.config.email.local_threepid_handling_disabled_due_to_email_config:
                 logger.warning(
                     "Adding emails have been disabled due to lack of an email config"
                 )
@@ -413,7 +413,7 @@ class EmailThreepidRequestTokenRestServlet(RestServlet):
 
             raise SynapseError(400, "Email is already in use", Codes.THREEPID_IN_USE)
 
-        if self.config.threepid_behaviour_email == ThreepidBehaviour.REMOTE:
+        if self.config.email.threepid_behaviour_email == ThreepidBehaviour.REMOTE:
             assert self.hs.config.account_threepid_delegate_email
 
             # Have the configured identity server handle the request
@@ -534,21 +534,21 @@ class AddThreepidEmailSubmitTokenServlet(RestServlet):
         self.config = hs.config
         self.clock = hs.get_clock()
         self.store = hs.get_datastore()
-        if self.config.threepid_behaviour_email == ThreepidBehaviour.LOCAL:
+        if self.config.email.threepid_behaviour_email == ThreepidBehaviour.LOCAL:
             self._failure_email_template = (
-                self.config.email_add_threepid_template_failure_html
+                self.config.email.email_add_threepid_template_failure_html
             )
 
     async def on_GET(self, request: Request) -> None:
-        if self.config.threepid_behaviour_email == ThreepidBehaviour.OFF:
-            if self.config.local_threepid_handling_disabled_due_to_email_config:
+        if self.config.email.threepid_behaviour_email == ThreepidBehaviour.OFF:
+            if self.config.email.local_threepid_handling_disabled_due_to_email_config:
                 logger.warning(
                     "Adding emails have been disabled due to lack of an email config"
                 )
             raise SynapseError(
                 400, "Adding an email to your account is disabled on this server"
             )
-        elif self.config.threepid_behaviour_email == ThreepidBehaviour.REMOTE:
+        elif self.config.email.threepid_behaviour_email == ThreepidBehaviour.REMOTE:
             raise SynapseError(
                 400,
                 "This homeserver is not validating threepids. Use an identity server "
@@ -575,7 +575,7 @@ class AddThreepidEmailSubmitTokenServlet(RestServlet):
                 return None
 
             # Otherwise show the success template
-            html = self.config.email_add_threepid_template_success_html_content
+            html = self.config.email.email_add_threepid_template_success_html_content
             status_code = 200
         except ThreepidValidationError as e:
             status_code = e.code
diff --git a/synapse/rest/client/auth.py b/synapse/rest/client/auth.py
index 7bb7801472..282861fae2 100644
--- a/synapse/rest/client/auth.py
+++ b/synapse/rest/client/auth.py
@@ -47,7 +47,7 @@ class AuthRestServlet(RestServlet):
         self.auth = hs.get_auth()
         self.auth_handler = hs.get_auth_handler()
         self.registration_handler = hs.get_registration_handler()
-        self.recaptcha_template = hs.config.recaptcha_template
+        self.recaptcha_template = hs.config.captcha.recaptcha_template
         self.terms_template = hs.config.terms_template
         self.registration_token_template = hs.config.registration_token_template
         self.success_template = hs.config.fallback_success_template
@@ -62,7 +62,7 @@ class AuthRestServlet(RestServlet):
                 session=session,
                 myurl="%s/r0/auth/%s/fallback/web"
                 % (CLIENT_API_PREFIX, LoginType.RECAPTCHA),
-                sitekey=self.hs.config.recaptcha_public_key,
+                sitekey=self.hs.config.captcha.recaptcha_public_key,
             )
         elif stagetype == LoginType.TERMS:
             html = self.terms_template.render(
@@ -70,7 +70,7 @@ class AuthRestServlet(RestServlet):
                 terms_url="%s_matrix/consent?v=%s"
                 % (
                     self.hs.config.server.public_baseurl,
-                    self.hs.config.user_consent_version,
+                    self.hs.config.consent.user_consent_version,
                 ),
                 myurl="%s/r0/auth/%s/fallback/web"
                 % (CLIENT_API_PREFIX, LoginType.TERMS),
@@ -118,7 +118,7 @@ class AuthRestServlet(RestServlet):
                     session=session,
                     myurl="%s/r0/auth/%s/fallback/web"
                     % (CLIENT_API_PREFIX, LoginType.RECAPTCHA),
-                    sitekey=self.hs.config.recaptcha_public_key,
+                    sitekey=self.hs.config.captcha.recaptcha_public_key,
                     error=e.msg,
                 )
             else:
@@ -139,7 +139,7 @@ class AuthRestServlet(RestServlet):
                     terms_url="%s_matrix/consent?v=%s"
                     % (
                         self.hs.config.server.public_baseurl,
-                        self.hs.config.user_consent_version,
+                        self.hs.config.consent.user_consent_version,
                     ),
                     myurl="%s/r0/auth/%s/fallback/web"
                     % (CLIENT_API_PREFIX, LoginType.TERMS),
diff --git a/synapse/rest/client/login.py b/synapse/rest/client/login.py
index a6ede7e2f3..d766e98dce 100644
--- a/synapse/rest/client/login.py
+++ b/synapse/rest/client/login.py
@@ -77,7 +77,7 @@ class LoginRestServlet(RestServlet):
 
         # SSO configuration.
         self.saml2_enabled = hs.config.saml2_enabled
-        self.cas_enabled = hs.config.cas_enabled
+        self.cas_enabled = hs.config.cas.cas_enabled
         self.oidc_enabled = hs.config.oidc_enabled
         self._msc2918_enabled = hs.config.access_token_lifetime is not None
 
@@ -559,7 +559,7 @@ def register_servlets(hs: "HomeServer", http_server: HttpServer) -> None:
     if hs.config.access_token_lifetime is not None:
         RefreshTokenServlet(hs).register(http_server)
     SsoRedirectServlet(hs).register(http_server)
-    if hs.config.cas_enabled:
+    if hs.config.cas.cas_enabled:
         CasTicketServlet(hs).register(http_server)
 
 
diff --git a/synapse/rest/client/password_policy.py b/synapse/rest/client/password_policy.py
index 0465fd2292..9f1908004b 100644
--- a/synapse/rest/client/password_policy.py
+++ b/synapse/rest/client/password_policy.py
@@ -35,8 +35,8 @@ class PasswordPolicyServlet(RestServlet):
     def __init__(self, hs: "HomeServer"):
         super().__init__()
 
-        self.policy = hs.config.password_policy
-        self.enabled = hs.config.password_policy_enabled
+        self.policy = hs.config.auth.password_policy
+        self.enabled = hs.config.auth.password_policy_enabled
 
     def on_GET(self, request: Request) -> Tuple[int, JsonDict]:
         if not self.enabled or not self.policy:
diff --git a/synapse/rest/client/register.py b/synapse/rest/client/register.py
index abe4d7e205..48b0062cf4 100644
--- a/synapse/rest/client/register.py
+++ b/synapse/rest/client/register.py
@@ -75,17 +75,19 @@ class EmailRegisterRequestTokenRestServlet(RestServlet):
         self.identity_handler = hs.get_identity_handler()
         self.config = hs.config
 
-        if self.hs.config.threepid_behaviour_email == ThreepidBehaviour.LOCAL:
+        if self.hs.config.email.threepid_behaviour_email == ThreepidBehaviour.LOCAL:
             self.mailer = Mailer(
                 hs=self.hs,
-                app_name=self.config.email_app_name,
-                template_html=self.config.email_registration_template_html,
-                template_text=self.config.email_registration_template_text,
+                app_name=self.config.email.email_app_name,
+                template_html=self.config.email.email_registration_template_html,
+                template_text=self.config.email.email_registration_template_text,
             )
 
     async def on_POST(self, request: SynapseRequest) -> Tuple[int, JsonDict]:
-        if self.hs.config.threepid_behaviour_email == ThreepidBehaviour.OFF:
-            if self.hs.config.local_threepid_handling_disabled_due_to_email_config:
+        if self.hs.config.email.threepid_behaviour_email == ThreepidBehaviour.OFF:
+            if (
+                self.hs.config.email.local_threepid_handling_disabled_due_to_email_config
+            ):
                 logger.warning(
                     "Email registration has been disabled due to lack of email config"
                 )
@@ -137,7 +139,7 @@ class EmailRegisterRequestTokenRestServlet(RestServlet):
 
             raise SynapseError(400, "Email is already in use", Codes.THREEPID_IN_USE)
 
-        if self.config.threepid_behaviour_email == ThreepidBehaviour.REMOTE:
+        if self.config.email.threepid_behaviour_email == ThreepidBehaviour.REMOTE:
             assert self.hs.config.account_threepid_delegate_email
 
             # Have the configured identity server handle the request
@@ -259,9 +261,9 @@ class RegistrationSubmitTokenServlet(RestServlet):
         self.clock = hs.get_clock()
         self.store = hs.get_datastore()
 
-        if self.config.threepid_behaviour_email == ThreepidBehaviour.LOCAL:
+        if self.config.email.threepid_behaviour_email == ThreepidBehaviour.LOCAL:
             self._failure_email_template = (
-                self.config.email_registration_template_failure_html
+                self.config.email.email_registration_template_failure_html
             )
 
     async def on_GET(self, request: Request, medium: str) -> None:
@@ -269,8 +271,8 @@ class RegistrationSubmitTokenServlet(RestServlet):
             raise SynapseError(
                 400, "This medium is currently not supported for registration"
             )
-        if self.config.threepid_behaviour_email == ThreepidBehaviour.OFF:
-            if self.config.local_threepid_handling_disabled_due_to_email_config:
+        if self.config.email.threepid_behaviour_email == ThreepidBehaviour.OFF:
+            if self.config.email.local_threepid_handling_disabled_due_to_email_config:
                 logger.warning(
                     "User registration via email has been disabled due to lack of email config"
                 )
@@ -303,7 +305,7 @@ class RegistrationSubmitTokenServlet(RestServlet):
                     return None
 
             # Otherwise show the success template
-            html = self.config.email_registration_template_success_html_content
+            html = self.config.email.email_registration_template_success_html_content
             status_code = 200
         except ThreepidValidationError as e:
             status_code = e.code
@@ -897,12 +899,12 @@ def _calculate_registration_flows(
         flows.append([LoginType.MSISDN, LoginType.EMAIL_IDENTITY])
 
     # Prepend m.login.terms to all flows if we're requiring consent
-    if config.user_consent_at_registration:
+    if config.consent.user_consent_at_registration:
         for flow in flows:
             flow.insert(0, LoginType.TERMS)
 
     # Prepend recaptcha to all flows if we're requiring captcha
-    if config.enable_registration_captcha:
+    if config.captcha.enable_registration_captcha:
         for flow in flows:
             flow.insert(0, LoginType.RECAPTCHA)
 
diff --git a/synapse/rest/consent/consent_resource.py b/synapse/rest/consent/consent_resource.py
index 06e0fbde22..fc634a492d 100644
--- a/synapse/rest/consent/consent_resource.py
+++ b/synapse/rest/consent/consent_resource.py
@@ -84,14 +84,15 @@ class ConsentResource(DirectServeHtmlResource):
         # this is required by the request_handler wrapper
         self.clock = hs.get_clock()
 
-        self._default_consent_version = hs.config.user_consent_version
-        if self._default_consent_version is None:
+        # Consent must be configured to create this resource.
+        default_consent_version = hs.config.consent.user_consent_version
+        consent_template_directory = hs.config.consent.user_consent_template_dir
+        if default_consent_version is None or consent_template_directory is None:
             raise ConfigError(
                 "Consent resource is enabled but user_consent section is "
                 "missing in config file."
             )
-
-        consent_template_directory = hs.config.user_consent_template_dir
+        self._default_consent_version = default_consent_version
 
         # TODO: switch to synapse.util.templates.build_jinja_env
         loader = jinja2.FileSystemLoader(consent_template_directory)
diff --git a/synapse/rest/synapse/client/password_reset.py b/synapse/rest/synapse/client/password_reset.py
index f2800bf2db..28a67f04e3 100644
--- a/synapse/rest/synapse/client/password_reset.py
+++ b/synapse/rest/synapse/client/password_reset.py
@@ -47,20 +47,20 @@ class PasswordResetSubmitTokenResource(DirectServeHtmlResource):
         self.store = hs.get_datastore()
 
         self._local_threepid_handling_disabled_due_to_email_config = (
-            hs.config.local_threepid_handling_disabled_due_to_email_config
+            hs.config.email.local_threepid_handling_disabled_due_to_email_config
         )
         self._confirmation_email_template = (
-            hs.config.email_password_reset_template_confirmation_html
+            hs.config.email.email_password_reset_template_confirmation_html
         )
         self._email_password_reset_template_success_html = (
-            hs.config.email_password_reset_template_success_html_content
+            hs.config.email.email_password_reset_template_success_html_content
         )
         self._failure_email_template = (
-            hs.config.email_password_reset_template_failure_html
+            hs.config.email.email_password_reset_template_failure_html
         )
 
         # This resource should not be mounted if threepid behaviour is not LOCAL
-        assert hs.config.threepid_behaviour_email == ThreepidBehaviour.LOCAL
+        assert hs.config.email.threepid_behaviour_email == ThreepidBehaviour.LOCAL
 
     async def _async_render_GET(self, request: Request) -> Tuple[int, bytes]:
         sid = parse_string(request, "sid", required=True)
diff --git a/synapse/server_notices/consent_server_notices.py b/synapse/server_notices/consent_server_notices.py
index 4e0f814035..e09a25591f 100644
--- a/synapse/server_notices/consent_server_notices.py
+++ b/synapse/server_notices/consent_server_notices.py
@@ -36,9 +36,11 @@ class ConsentServerNotices:
 
         self._users_in_progress: Set[str] = set()
 
-        self._current_consent_version = hs.config.user_consent_version
-        self._server_notice_content = hs.config.user_consent_server_notice_content
-        self._send_to_guests = hs.config.user_consent_server_notice_to_guests
+        self._current_consent_version = hs.config.consent.user_consent_version
+        self._server_notice_content = (
+            hs.config.consent.user_consent_server_notice_content
+        )
+        self._send_to_guests = hs.config.consent.user_consent_server_notice_to_guests
 
         if self._server_notice_content is not None:
             if not self._server_notices_manager.is_enabled():
@@ -63,6 +65,9 @@ class ConsentServerNotices:
             # not enabled
             return
 
+        # A consent version must be given.
+        assert self._current_consent_version is not None
+
         # make sure we don't send two messages to the same user at once
         if user_id in self._users_in_progress:
             return
diff --git a/synapse/storage/databases/main/appservice.py b/synapse/storage/databases/main/appservice.py
index e2d1b758bd..2da2659f41 100644
--- a/synapse/storage/databases/main/appservice.py
+++ b/synapse/storage/databases/main/appservice.py
@@ -60,7 +60,7 @@ def _make_exclusive_regex(
 class ApplicationServiceWorkerStore(SQLBaseStore):
     def __init__(self, database: DatabasePool, db_conn: Connection, hs: "HomeServer"):
         self.services_cache = load_appservices(
-            hs.hostname, hs.config.app_service_config_files
+            hs.hostname, hs.config.appservice.app_service_config_files
         )
         self.exclusive_user_regex = _make_exclusive_regex(self.services_cache)
 
diff --git a/synapse/storage/databases/main/monthly_active_users.py b/synapse/storage/databases/main/monthly_active_users.py
index d213b26703..b76ee51a9b 100644
--- a/synapse/storage/databases/main/monthly_active_users.py
+++ b/synapse/storage/databases/main/monthly_active_users.py
@@ -63,7 +63,7 @@ class MonthlyActiveUsersWorkerStore(SQLBaseStore):
         """Generates current count of monthly active users broken down by service.
         A service is typically an appservice but also includes native matrix users.
         Since the `monthly_active_users` table is populated from the `user_ips` table
-        `config.track_appservice_user_ips` must be set to `true` for this
+        `config.appservice.track_appservice_user_ips` must be set to `true` for this
         method to return anything other than native matrix users.
 
         Returns:
diff --git a/synapse/storage/databases/main/registration.py b/synapse/storage/databases/main/registration.py
index fafadb88fc..52ef9deede 100644
--- a/synapse/storage/databases/main/registration.py
+++ b/synapse/storage/databases/main/registration.py
@@ -388,7 +388,7 @@ class RegistrationWorkerStore(CacheInvalidationWorkerStore):
             "get_users_expiring_soon",
             select_users_txn,
             self._clock.time_msec(),
-            self.config.account_validity_renew_at,
+            self.config.account_validity.account_validity_renew_at,
         )
 
     async def set_renewal_mail_status(self, user_id: str, email_sent: bool) -> None:
diff --git a/synapse/storage/prepare_database.py b/synapse/storage/prepare_database.py
index d4754c904c..f31880b8ec 100644
--- a/synapse/storage/prepare_database.py
+++ b/synapse/storage/prepare_database.py
@@ -545,7 +545,7 @@ def _apply_module_schemas(
         database_engine:
         config: application config
     """
-    for (mod, _config) in config.password_providers:
+    for (mod, _config) in config.authproviders.password_providers:
         if not hasattr(mod, "get_db_schema_files"):
             continue
         modname = ".".join((mod.__module__, mod.__name__))
diff --git a/synapse/storage/schema/main/delta/30/as_users.py b/synapse/storage/schema/main/delta/30/as_users.py
index 8a1f340083..22a7901e15 100644
--- a/synapse/storage/schema/main/delta/30/as_users.py
+++ b/synapse/storage/schema/main/delta/30/as_users.py
@@ -33,7 +33,7 @@ def run_upgrade(cur, database_engine, config, *args, **kwargs):
 
     config_files = []
     try:
-        config_files = config.app_service_config_files
+        config_files = config.appservice.app_service_config_files
     except AttributeError:
         logger.warning("Could not get app_service_config_files from config")
         pass
diff --git a/tests/rest/admin/test_room.py b/tests/rest/admin/test_room.py
index e798513ac1..0fa55e03b4 100644
--- a/tests/rest/admin/test_room.py
+++ b/tests/rest/admin/test_room.py
@@ -47,7 +47,7 @@ class DeleteRoomTestCase(unittest.HomeserverTestCase):
 
     def prepare(self, reactor, clock, hs):
         self.event_creation_handler = hs.get_event_creation_handler()
-        hs.config.user_consent_version = "1"
+        hs.config.consent.user_consent_version = "1"
 
         consent_uri_builder = Mock()
         consent_uri_builder.build_user_consent_uri.return_value = "http://example.com"
diff --git a/tests/rest/client/test_login.py b/tests/rest/client/test_login.py
index f5c195a075..414c8781a9 100644
--- a/tests/rest/client/test_login.py
+++ b/tests/rest/client/test_login.py
@@ -97,7 +97,7 @@ class LoginRestServletTestCase(unittest.HomeserverTestCase):
         self.hs.config.enable_registration = True
         self.hs.config.registrations_require_3pid = []
         self.hs.config.auto_join_rooms = []
-        self.hs.config.enable_registration_captcha = False
+        self.hs.config.captcha.enable_registration_captcha = False
 
         return self.hs
 
diff --git a/tests/storage/test_appservice.py b/tests/storage/test_appservice.py
index 666bffe257..ebadf47948 100644
--- a/tests/storage/test_appservice.py
+++ b/tests/storage/test_appservice.py
@@ -41,9 +41,8 @@ class ApplicationServiceStoreTestCase(unittest.TestCase):
             self.addCleanup, federation_sender=Mock(), federation_client=Mock()
         )
 
-        hs.config.app_service_config_files = self.as_yaml_files
+        hs.config.appservice.app_service_config_files = self.as_yaml_files
         hs.config.caches.event_cache_size = 1
-        hs.config.password_providers = []
 
         self.as_token = "token1"
         self.as_url = "some_url"
@@ -108,9 +107,8 @@ class ApplicationServiceTransactionStoreTestCase(unittest.TestCase):
             self.addCleanup, federation_sender=Mock(), federation_client=Mock()
         )
 
-        hs.config.app_service_config_files = self.as_yaml_files
+        hs.config.appservice.app_service_config_files = self.as_yaml_files
         hs.config.caches.event_cache_size = 1
-        hs.config.password_providers = []
 
         self.as_list = [
             {"token": "token1", "url": "https://matrix-as.org", "id": "id_1"},
@@ -496,9 +494,8 @@ class ApplicationServiceStoreConfigTestCase(unittest.TestCase):
             self.addCleanup, federation_sender=Mock(), federation_client=Mock()
         )
 
-        hs.config.app_service_config_files = [f1, f2]
+        hs.config.appservice.app_service_config_files = [f1, f2]
         hs.config.caches.event_cache_size = 1
-        hs.config.password_providers = []
 
         database = hs.get_datastores().databases[0]
         ApplicationServiceStore(
@@ -514,7 +511,7 @@ class ApplicationServiceStoreConfigTestCase(unittest.TestCase):
             self.addCleanup, federation_sender=Mock(), federation_client=Mock()
         )
 
-        hs.config.app_service_config_files = [f1, f2]
+        hs.config.appservice.app_service_config_files = [f1, f2]
         hs.config.caches.event_cache_size = 1
         hs.config.password_providers = []
 
@@ -540,9 +537,8 @@ class ApplicationServiceStoreConfigTestCase(unittest.TestCase):
             self.addCleanup, federation_sender=Mock(), federation_client=Mock()
         )
 
-        hs.config.app_service_config_files = [f1, f2]
+        hs.config.appservice.app_service_config_files = [f1, f2]
         hs.config.caches.event_cache_size = 1
-        hs.config.password_providers = []
 
         with self.assertRaises(ConfigError) as cm:
             database = hs.get_datastores().databases[0]
diff --git a/tests/storage/test_cleanup_extrems.py b/tests/storage/test_cleanup_extrems.py
index da98733ce8..7cc5e621ba 100644
--- a/tests/storage/test_cleanup_extrems.py
+++ b/tests/storage/test_cleanup_extrems.py
@@ -258,7 +258,7 @@ class CleanupExtremDummyEventsTestCase(HomeserverTestCase):
         info, _ = self.get_success(self.room_creator.create_room(self.requester, {}))
         self.room_id = info["room_id"]
         self.event_creator = homeserver.get_event_creation_handler()
-        homeserver.config.user_consent_version = self.CONSENT_VERSION
+        homeserver.config.consent.user_consent_version = self.CONSENT_VERSION
 
     def test_send_dummy_event(self):
         self._create_extremity_rich_graph()