Merge tag 'v1.37.0' into babolivier/dinsic_1.41.0

Synapse 1.37.0 (2021-06-29)
===========================

This release deprecates the current spam checker interface. See the [upgrade notes](https://matrix-org.github.io/synapse/develop/upgrade#deprecation-of-the-current-spam-checker-interface) for more information on how to update to the new generic module interface.

This release also removes support for fetching and renewing TLS certificates using the ACME v1 protocol, which has been fully decommissioned by Let's Encrypt on June 1st 2021. Admins previously using this feature should use a [reverse proxy](https://matrix-org.github.io/synapse/develop/reverse_proxy.html) to handle TLS termination, or use an external ACME client (such as [certbot](https://certbot.eff.org/)) to retrieve a certificate and key and provide them to Synapse using the `tls_certificate_path` and `tls_private_key_path` configuration settings.

Synapse 1.37.0rc1 (2021-06-24)
==============================

Features
--------

- Implement "room knocking" as per [MSC2403](https://github.com/matrix-org/matrix-doc/pull/2403). Contributed by @Sorunome and anoa. ([\#6739](https://github.com/matrix-org/synapse/issues/6739), [\#9359](https://github.com/matrix-org/synapse/issues/9359), [\#10167](https://github.com/matrix-org/synapse/issues/10167), [\#10212](https://github.com/matrix-org/synapse/issues/10212), [\#10227](https://github.com/matrix-org/synapse/issues/10227))
- Add experimental support for backfilling history into rooms ([MSC2716](https://github.com/matrix-org/matrix-doc/pull/2716)). ([\#9247](https://github.com/matrix-org/synapse/issues/9247))
- Implement a generic interface for third-party plugin modules. ([\#10062](https://github.com/matrix-org/synapse/issues/10062), [\#10206](https://github.com/matrix-org/synapse/issues/10206))
- Implement config option `sso.update_profile_information` to sync SSO users' profile information with the identity provider each time they login. Currently only displayname is supported. ([\#10108](https://github.com/matrix-org/synapse/issues/10108))
- Ensure that errors during startup are written to the logs and the console. ([\#10191](https://github.com/matrix-org/synapse/issues/10191))

Bugfixes
--------

- Fix a bug introduced in Synapse v1.25.0 that prevented the `ip_range_whitelist` configuration option from working for federation and identity servers. Contributed by @mikure. ([\#10115](https://github.com/matrix-org/synapse/issues/10115))
- Remove a broken import line in Synapse's `admin_cmd` worker. Broke in Synapse v1.33.0. ([\#10154](https://github.com/matrix-org/synapse/issues/10154))
- Fix a bug introduced in Synapse v1.21.0 which could cause `/sync` to return immediately with an empty response. ([\#10157](https://github.com/matrix-org/synapse/issues/10157), [\#10158](https://github.com/matrix-org/synapse/issues/10158))
- Fix a minor bug in the response to `/_matrix/client/r0/user/{user}/openid/request_token` causing `expires_in` to be a float instead of an integer. Contributed by @lukaslihotzki. ([\#10175](https://github.com/matrix-org/synapse/issues/10175))
- Always require users to re-authenticate for dangerous operations: deactivating an account, modifying an account password, and adding 3PIDs. ([\#10184](https://github.com/matrix-org/synapse/issues/10184))
- Fix a bug introduced in Synpase v1.7.2 where remote server count metrics collection would be incorrectly delayed on startup. Found by @heftig. ([\#10195](https://github.com/matrix-org/synapse/issues/10195))
- Fix a bug introduced in Synapse v1.35.1 where an `allow` key of a `m.room.join_rules` event could be applied for incorrect room versions and configurations. ([\#10208](https://github.com/matrix-org/synapse/issues/10208))
- Fix performance regression in responding to user key requests over federation. Introduced in Synapse v1.34.0rc1. ([\#10221](https://github.com/matrix-org/synapse/issues/10221))

Improved Documentation
----------------------

- Add a new guide to decoding request logs. ([\#8436](https://github.com/matrix-org/synapse/issues/8436))
- Mention in the sample homeserver config that you may need to configure max upload size in your reverse proxy. Contributed by @aaronraimist. ([\#10122](https://github.com/matrix-org/synapse/issues/10122))
- Fix broken links in documentation. ([\#10180](https://github.com/matrix-org/synapse/issues/10180))
- Deploy a snapshot of the documentation website upon each new Synapse release. ([\#10198](https://github.com/matrix-org/synapse/issues/10198))

Deprecations and Removals
-------------------------

- The current spam checker interface is deprecated in favour of a new generic modules system. See the [upgrade notes](https://matrix-org.github.io/synapse/develop/upgrade#deprecation-of-the-current-spam-checker-interface) for more information on how to update to the new system. ([\#10062](https://github.com/matrix-org/synapse/issues/10062), [\#10210](https://github.com/matrix-org/synapse/issues/10210), [\#10238](https://github.com/matrix-org/synapse/issues/10238))
- Stop supporting the unstable spaces prefixes from MSC1772. ([\#10161](https://github.com/matrix-org/synapse/issues/10161))
- Remove Synapse's support for automatically fetching and renewing certificates using the ACME v1 protocol. This protocol has been fully turned off by Let's Encrypt for existing installations on June 1st 2021. Admins previously using this feature should use a [reverse proxy](https://matrix-org.github.io/synapse/develop/reverse_proxy.html) to handle TLS termination, or use an external ACME client (such as [certbot](https://certbot.eff.org/)) to retrieve a certificate and key and provide them to Synapse using the `tls_certificate_path` and `tls_private_key_path` configuration settings. ([\#10194](https://github.com/matrix-org/synapse/issues/10194))

Internal Changes
----------------

- Update the database schema versioning to support gradual migration away from legacy tables. ([\#9933](https://github.com/matrix-org/synapse/issues/9933))
- Add type hints to the federation servlets. ([\#10080](https://github.com/matrix-org/synapse/issues/10080))
- Improve OpenTracing for event persistence. ([\#10134](https://github.com/matrix-org/synapse/issues/10134), [\#10193](https://github.com/matrix-org/synapse/issues/10193))
- Clean up the interface for injecting OpenTracing over HTTP. ([\#10143](https://github.com/matrix-org/synapse/issues/10143))
- Limit the number of in-flight `/keys/query` requests from a single device. ([\#10144](https://github.com/matrix-org/synapse/issues/10144))
- Refactor EventPersistenceQueue. ([\#10145](https://github.com/matrix-org/synapse/issues/10145))
- Document `SYNAPSE_TEST_LOG_LEVEL` to see the logger output when running tests. ([\#10148](https://github.com/matrix-org/synapse/issues/10148))
- Update the Complement build tags in GitHub Actions to test currently experimental features. ([\#10155](https://github.com/matrix-org/synapse/issues/10155))
- Add a `synapse_federation_soft_failed_events_total` metric to track how often events are soft failed. ([\#10156](https://github.com/matrix-org/synapse/issues/10156))
- Fetch the corresponding complement branch when performing CI. ([\#10160](https://github.com/matrix-org/synapse/issues/10160))
- Add some developer documentation about boolean columns in database schemas. ([\#10164](https://github.com/matrix-org/synapse/issues/10164))
- Add extra logging fields to better debug where events are being soft failed. ([\#10168](https://github.com/matrix-org/synapse/issues/10168))
- Add debug logging for when we enter and exit `Measure` blocks. ([\#10183](https://github.com/matrix-org/synapse/issues/10183))
- Improve comments in structured logging code. ([\#10188](https://github.com/matrix-org/synapse/issues/10188))
- Update [MSC3083](https://github.com/matrix-org/matrix-doc/pull/3083) support with modifications from the MSC. ([\#10189](https://github.com/matrix-org/synapse/issues/10189))
- Remove redundant DNS lookup limiter. ([\#10190](https://github.com/matrix-org/synapse/issues/10190))
- Upgrade `black` linting tool to 21.6b0. ([\#10197](https://github.com/matrix-org/synapse/issues/10197))
- Expose OpenTracing trace id in response headers. ([\#10199](https://github.com/matrix-org/synapse/issues/10199))

1 files changed, 82 insertions, 39 deletions

diff --git a/synapse/storage/prepare_database.py b/synapse/storage/prepare_database.py

index 3799d46734..683e5e3b90 100644
--- a/synapse/storage/prepare_database.py
+++ b/synapse/storage/prepare_database.py
@@ -1,5 +1,4 @@
-# Copyright 2014 - 2016 OpenMarket Ltd
-# Copyright 2018 New Vector Ltd
+# Copyright 2014 - 2021 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.
@@ -26,7 +25,7 @@ from synapse.config.homeserver import HomeServerConfig
 from synapse.storage.database import LoggingDatabaseConnection
 from synapse.storage.engines import BaseDatabaseEngine
 from synapse.storage.engines.postgres import PostgresEngine
-from synapse.storage.schema import SCHEMA_VERSION
+from synapse.storage.schema import SCHEMA_COMPAT_VERSION, SCHEMA_VERSION
 from synapse.storage.types import Cursor
 
 logger = logging.getLogger(__name__)
@@ -59,6 +58,28 @@ UNAPPLIED_DELTA_ON_WORKER_ERROR = (
 )
 
 
+@attr.s
+class _SchemaState:
+    current_version: int = attr.ib()
+    """The current schema version of the database"""
+
+    compat_version: Optional[int] = attr.ib()
+    """The SCHEMA_VERSION of the oldest version of Synapse for this database
+
+    If this is None, we have an old version of the database without the necessary
+    table.
+    """
+
+    applied_deltas: Collection[str] = attr.ib(factory=tuple)
+    """Any delta files for `current_version` which have already been applied"""
+
+    upgraded: bool = attr.ib(default=False)
+    """Whether the current state was reached by applying deltas.
+
+    If False, we have run the full schema for `current_version`, and have applied no
+    deltas since. If True, we have run some deltas since the original creation."""
+
+
 def prepare_database(
     db_conn: LoggingDatabaseConnection,
     database_engine: BaseDatabaseEngine,
@@ -96,12 +117,11 @@ def prepare_database(
         version_info = _get_or_create_schema_state(cur, database_engine)
 
         if version_info:
-            user_version, delta_files, upgraded = version_info
             logger.info(
                 "%r: Existing schema is %i (+%i deltas)",
                 databases,
-                user_version,
-                len(delta_files),
+                version_info.current_version,
+                len(version_info.applied_deltas),
             )
 
             # config should only be None when we are preparing an in-memory SQLite db,
@@ -113,16 +133,18 @@ def prepare_database(
 
             # if it's a worker app, refuse to upgrade the database, to avoid multiple
             # workers doing it at once.
-            if config.worker_app is not None and user_version != SCHEMA_VERSION:
+            if (
+                config.worker_app is not None
+                and version_info.current_version != SCHEMA_VERSION
+            ):
                 raise UpgradeDatabaseException(
-                    OUTDATED_SCHEMA_ON_WORKER_ERROR % (SCHEMA_VERSION, user_version)
+                    OUTDATED_SCHEMA_ON_WORKER_ERROR
+                    % (SCHEMA_VERSION, version_info.current_version)
                 )
 
             _upgrade_existing_database(
                 cur,
-                user_version,
-                delta_files,
-                upgraded,
+                version_info,
                 database_engine,
                 config,
                 databases=databases,
@@ -261,9 +283,7 @@ def _setup_new_database(
 
     _upgrade_existing_database(
         cur,
-        current_version=max_current_ver,
-        applied_delta_files=[],
-        upgraded=False,
+        _SchemaState(current_version=max_current_ver, compat_version=None),
         database_engine=database_engine,
         config=None,
         databases=databases,
@@ -273,9 +293,7 @@ def _setup_new_database(
 
 def _upgrade_existing_database(
     cur: Cursor,
-    current_version: int,
-    applied_delta_files: List[str],
-    upgraded: bool,
+    current_schema_state: _SchemaState,
     database_engine: BaseDatabaseEngine,
     config: Optional[HomeServerConfig],
     databases: Collection[str],
@@ -321,12 +339,8 @@ def _upgrade_existing_database(
 
     Args:
         cur
-        current_version: The current version of the schema.
-        applied_delta_files: A list of deltas that have already been applied.
-        upgraded: Whether the current version was generated by having
-            applied deltas or from full schema file. If `True` the function
-            will never apply delta files for the given `current_version`, since
-            the current_version wasn't generated by applying those delta files.
+        current_schema_state: The current version of the schema, as
+            returned by _get_or_create_schema_state
         database_engine
         config:
             None if we are initialising a blank database, otherwise the application
@@ -337,13 +351,16 @@ def _upgrade_existing_database(
             upgrade portions of the delta scripts.
     """
     if is_empty:
-        assert not applied_delta_files
+        assert not current_schema_state.applied_deltas
     else:
         assert config
 
     is_worker = config and config.worker_app is not None
 
-    if current_version > SCHEMA_VERSION:
+    if (
+        current_schema_state.compat_version is not None
+        and current_schema_state.compat_version > SCHEMA_VERSION
+    ):
         raise ValueError(
             "Cannot use this database as it is too "
             + "new for the server to understand"
@@ -357,14 +374,26 @@ def _upgrade_existing_database(
         assert config is not None
         check_database_before_upgrade(cur, database_engine, config)
 
-    start_ver = current_version
+    # update schema_compat_version before we run any upgrades, so that if synapse
+    # gets downgraded again, it won't try to run against the upgraded database.
+    if (
+        current_schema_state.compat_version is None
+        or current_schema_state.compat_version < SCHEMA_COMPAT_VERSION
+    ):
+        cur.execute("DELETE FROM schema_compat_version")
+        cur.execute(
+            "INSERT INTO schema_compat_version(compat_version) VALUES (?)",
+            (SCHEMA_COMPAT_VERSION,),
+        )
+
+    start_ver = current_schema_state.current_version
 
     # if we got to this schema version by running a full_schema rather than a series
     # of deltas, we should not run the deltas for this version.
-    if not upgraded:
+    if not current_schema_state.upgraded:
         start_ver += 1
 
-    logger.debug("applied_delta_files: %s", applied_delta_files)
+    logger.debug("applied_delta_files: %s", current_schema_state.applied_deltas)
 
     if isinstance(database_engine, PostgresEngine):
         specific_engine_extension = ".postgres"
@@ -440,7 +469,7 @@ def _upgrade_existing_database(
             absolute_path = entry.absolute_path
 
             logger.debug("Found file: %s (%s)", relative_path, absolute_path)
-            if relative_path in applied_delta_files:
+            if relative_path in current_schema_state.applied_deltas:
                 continue
 
             root_name, ext = os.path.splitext(file_name)
@@ -621,7 +650,7 @@ def execute_statements_from_stream(cur: Cursor, f: TextIO) -> None:
 
 def _get_or_create_schema_state(
     txn: Cursor, database_engine: BaseDatabaseEngine
-) -> Optional[Tuple[int, List[str], bool]]:
+) -> Optional[_SchemaState]:
     # Bluntly try creating the schema_version tables.
     sql_path = os.path.join(schema_path, "common", "schema_version.sql")
     executescript(txn, sql_path)
@@ -629,17 +658,31 @@ def _get_or_create_schema_state(
     txn.execute("SELECT version, upgraded FROM schema_version")
     row = txn.fetchone()
 
+    if row is None:
+        # new database
+        return None
+
+    current_version = int(row[0])
+    upgraded = bool(row[1])
+
+    compat_version: Optional[int] = None
+    txn.execute("SELECT compat_version FROM schema_compat_version")
+    row = txn.fetchone()
     if row is not None:
-        current_version = int(row[0])
-        txn.execute(
-            "SELECT file FROM applied_schema_deltas WHERE version >= ?",
-            (current_version,),
-        )
-        applied_deltas = [d for d, in txn]
-        upgraded = bool(row[1])
-        return current_version, applied_deltas, upgraded
+        compat_version = int(row[0])
+
+    txn.execute(
+        "SELECT file FROM applied_schema_deltas WHERE version >= ?",
+        (current_version,),
+    )
+    applied_deltas = tuple(d for d, in txn)
 
-    return None
+    return _SchemaState(
+        current_version=current_version,
+        compat_version=compat_version,
+        applied_deltas=applied_deltas,
+        upgraded=upgraded,
+    )
 
 
 @attr.s(slots=True)