Refuse to start if sqlite is older than 3.11.0

INSTALL.md

@@ -133,6 +133,11 @@ sudo yum install libtiff-devel libjpeg-devel libzip-devel freetype-devel \
 sudo yum groupinstall "Development Tools"
 ```
 
+Note that Synapse does not support versions of SQLite before 3.11, and CentOS 7
+uses SQLite 3.7. You may be able to work around this by installing a more
+recent SQLite version, but it is recommended that you instead use a Postgres
+database: see [docs/postgres.md](docs/postgres.md).
+
 #### macOS
 
 Installing prerequisites on macOS:

changelog.d/6675.removal

@@ -0,0 +1 @@
+Synapse no longer supports versions of SQLite before 3.11, and will refuse to start when configured to use an older version. Administrators are recommended to migrate their database to Postgres (see instructions [here](docs/postgres.md)).

scripts/synapse_port_db

@@ -447,37 +447,32 @@ class Porter(object):
             else:
                 return
 
-    def setup_db(self, db_config: DatabaseConnectionConfig, engine):
-        db_conn = make_conn(db_config, engine)
-        prepare_database(db_conn, engine, config=None)
-
-        db_conn.commit()
-
-        return db_conn
-
-    @defer.inlineCallbacks
-    def build_db_store(self, db_config: DatabaseConnectionConfig):
+    def build_db_store(
+        self, db_config: DatabaseConnectionConfig, allow_outdated_version: bool = False,
+    ):
         """Builds and returns a database store using the provided configuration.
 
         Args:
-            config: The database configuration
+            db_config: The database configuration
+            allow_outdated_version: True to suppress errors about the database server
+                version being too old to run a complete synapse
 
         Returns:
             The built Store object.
         """
         self.progress.set_state("Preparing %s" % db_config.config["name"])
 
         engine = create_engine(db_config.config)
-        conn = self.setup_db(db_config, engine)
 
         hs = MockHomeserver(self.hs_config)
 
-        store = Store(Database(hs, db_config, engine), conn, hs)
-
-        yield store.db.runInteraction(
-            "%s_engine.check_database" % db_config.config["name"],
-            engine.check_database,
-        )
+        with make_conn(db_config, engine) as db_conn:
+            engine.check_database(
+                db_conn, allow_outdated_version=allow_outdated_version
+            )
+            prepare_database(db_conn, engine, config=None)
+            store = Store(Database(hs, db_config, engine), db_conn, hs)
+            db_conn.commit()
 
         return store
 
@@ -502,8 +497,10 @@ class Porter(object):
     @defer.inlineCallbacks
     def run(self):
         try:
-            self.sqlite_store = yield self.build_db_store(
-                DatabaseConnectionConfig("master-sqlite", self.sqlite_config)
+            # we allow people to port away from outdated versions of sqlite.
+            self.sqlite_store = self.build_db_store(
+                DatabaseConnectionConfig("master-sqlite", self.sqlite_config),
+                allow_outdated_version=True,
             )
 
             # Check if all background updates are done, abort if not.
@@ -518,7 +515,7 @@ class Porter(object):
                 )
                 defer.returnValue(None)
 
-            self.postgres_store = yield self.build_db_store(
+            self.postgres_store = self.build_db_store(
                 self.hs_config.get_single_database()
             )
 

synapse/storage/data_stores/__init__.py

@@ -47,7 +47,7 @@ def __init__(self, main_store_class, hs):
             with make_conn(database_config, engine) as db_conn:
                 logger.info("Preparing database %r...", db_name)
 
-                engine.check_database(db_conn.cursor())
+                engine.check_database(db_conn)
                 prepare_database(
                     db_conn, engine, hs.config, data_stores=database_config.data_stores,
                 )

synapse/storage/engines/postgres.py

@@ -32,30 +32,30 @@ def _disable_bytes_adapter(_):
         self.synchronous_commit = database_config.get("synchronous_commit", True)
         self._version = None  # unknown as yet
 
-    def check_database(self, txn):
-        txn.execute("SHOW SERVER_ENCODING")
-        rows = txn.fetchall()
-        if rows and rows[0][0] != "UTF8":
-            raise IncorrectDatabaseSetup(
-                "Database has incorrect encoding: '%s' instead of 'UTF8'\n"
-                "See docs/postgres.rst for more information." % (rows[0][0],)
-            )
-
-    def convert_param_style(self, sql):
-        return sql.replace("?", "%s")
-
-    def on_new_connection(self, db_conn):
-
+    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
 
         # Are we on a supported PostgreSQL version?
-        if self._version < 90500:
+        if not allow_outdated_version and self._version < 90500:
             raise RuntimeError("Synapse requires PostgreSQL 9.5+ or above.")
 
+        with db_conn.cursor() as txn:
+            txn.execute("SHOW SERVER_ENCODING")
+            rows = txn.fetchall()
+            if rows and rows[0][0] != "UTF8":
+                raise IncorrectDatabaseSetup(
+                    "Database has incorrect encoding: '%s' instead of 'UTF8'\n"
+                    "See docs/postgres.rst for more information." % (rows[0][0],)
+                )
+
+    def convert_param_style(self, sql):
+        return sql.replace("?", "%s")
+
+    def on_new_connection(self, db_conn):
         db_conn.set_isolation_level(
             self.module.extensions.ISOLATION_LEVEL_REPEATABLE_READ
         )
@@ -119,8 +119,8 @@ def server_version(self):
         Returns:
             string
         """
-        # note that this is a bit of a hack because it relies on on_new_connection
-        # having been called at least once. Still, that should be a safe bet here.
+        # note that this is a bit of a hack because it relies on check_database
+        # having been called. Still, that should be a safe bet here.
         numver = self._version
         assert numver is not None
 

synapse/storage/engines/sqlite.py

@@ -53,8 +53,11 @@ def supports_using_any_list(self):
         """
         return False
 
-    def check_database(self, txn):
-        pass
+    def check_database(self, db_conn, allow_outdated_version: bool = False):
+        if not allow_outdated_version:
+            version = self.module.sqlite_version_info
+            if version < (3, 11, 0):
+                raise RuntimeError("Synapse requires sqlite 3.11 or above.")
 
     def convert_param_style(self, sql):
         return sql