WIP strict mypy for sydent.db

sydent/db/accounts.py

@@ -12,7 +12,7 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-from typing import TYPE_CHECKING, Optional
+from typing import TYPE_CHECKING, Optional, cast
 
 from sydent.users.accounts import Account
 
@@ -104,6 +104,7 @@ def delToken(self, token: str) -> int:
             "delete from tokens where token = ?",
             (token,),
         )
-        deleted = cur.rowcount
+        # Cast safety: DBAPI-2 says this is a "number"; c.f. python/typeshed#6150
+        deleted = cast(int, cur.rowcount)
         self.sydent.db.commit()
         return deleted

sydent/db/hashing_metadata.py

@@ -15,7 +15,7 @@
 # Actions on the hashing_metadata table which is defined in the migration process in
 # sqlitedb.py
 from sqlite3 import Cursor
-from typing import TYPE_CHECKING, Callable, Optional
+from typing import TYPE_CHECKING, Callable, Optional, Tuple
 
 if TYPE_CHECKING:
     from sydent.sydent import Sydent
@@ -33,7 +33,13 @@ def get_lookup_pepper(self) -> Optional[str]:
         """
         cur = self.sydent.db.cursor()
         res = cur.execute("select lookup_pepper from hashing_metadata")
-        row = res.fetchone()
+        # Annotation safety: lookup_pepper is marked as varchar(256) in the
+        # schema, so could be null. I.e. `row` should strictly be
+        # Optional[Tuple[Optional[str]].
+        # But I think the application code is such that either
+        #  - hashing_metadata contains no rows
+        #  - or it contains exactly one row with a nonnull lookup_pepper.
+        row: Optional[Tuple[str]] = res.fetchone()
 
         if not row:
             return None

sydent/db/invite_tokens.py

@@ -12,7 +12,7 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 import time
-from typing import TYPE_CHECKING, Dict, List, Optional, Union
+from typing import TYPE_CHECKING, Dict, List, Optional, Tuple, Union, cast
 
 if TYPE_CHECKING:
     from sydent.sydent import Sydent
@@ -152,7 +152,9 @@ def validateEphemeralPublicKey(self, publicKey: str) -> bool:
             (publicKey,),
         )
         self.sydent.db.commit()
-        return cur.rowcount > 0
+        # Cast safety: DBAPI-2 says this is a "number"; c.f. python/typeshed#6150
+        rows = cast(int, cur.rowcount)
+        return rows > 0
 
     def getSenderForToken(self, token: str) -> Optional[str]:
         """
@@ -165,7 +167,7 @@ def getSenderForToken(self, token: str) -> Optional[str]:
         """
         cur = self.sydent.db.cursor()
         res = cur.execute("SELECT sender FROM invite_tokens WHERE token = ?", (token,))
-        rows = res.fetchall()
+        rows: List[Tuple[str]] = res.fetchall()
         if rows:
             return rows[0][0]
         return None

sydent/db/peers.py

@@ -12,7 +12,7 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-from typing import TYPE_CHECKING, Dict, List, Optional
+from typing import TYPE_CHECKING, Dict, List, Optional, Tuple
 
 from sydent.replication.peer import RemotePeer
 
@@ -39,11 +39,16 @@ def getPeerByName(self, name: str) -> Optional[RemotePeer]:
             (name,),
         )
 
-        serverName = None
-        port = None
-        lastSentVer = None
-        pubkeys = {}
+        # Type safety: if the query returns no rows, we'll pubkeys will be empty
+        # and we'll return None before using serverName. Otherwise, we'll read
+        # at least one row and assign serverName a string value, because the
+        # `name` column is declared `not null` in the DB.
+        serverName: str = None  # type: ignore[assignment]
+        port: Optional[int] = None
+        lastSentVer: Optional[int] = None
+        pubkeys: Dict[str, str] = {}
 
+        row: Tuple[str, Optional[int], Optional[int], str, str]
         for row in res.fetchall():
             serverName = row[0]
             port = row[1]

sydent/db/sqlitedb.py

@@ -16,7 +16,7 @@
 import logging
 import os
 import sqlite3
-from typing import TYPE_CHECKING
+from typing import TYPE_CHECKING, Tuple
 
 if TYPE_CHECKING:
     from sydent.sydent import Sydent
@@ -42,7 +42,7 @@ def __init__(self, syd: "Sydent") -> None:
             self._createSchema()
         self._upgradeSchema()
 
-    def _createSchema(self):
+    def _createSchema(self) -> None:
         logger.info("Running schema files...")
         schemaDir = os.path.dirname(__file__)
 
@@ -64,7 +64,7 @@ def _createSchema(self):
         c.close()
         self.db.commit()
 
-    def _upgradeSchema(self):
+    def _upgradeSchema(self) -> None:
         curVer = self._getSchemaVersion()
 
         if curVer < 1:
@@ -212,13 +212,13 @@ def _upgradeSchema(self):
             logger.info("v4 -> v5 schema migration complete")
             self._setSchemaVersion(5)
 
-    def _getSchemaVersion(self):
+    def _getSchemaVersion(self) -> int:
         cur = self.db.cursor()
         cur.execute("PRAGMA user_version")
-        row = cur.fetchone()
+        row: Tuple[int] = cur.fetchone()
         return row[0]
 
-    def _setSchemaVersion(self, ver):
+    def _setSchemaVersion(self, ver: int) -> None:
         cur = self.db.cursor()
         # NB. pragma doesn't support variable substitution so we
         # do it in python (as a decimal so we don't risk SQL injection)

sydent/db/threepid_associations.py

@@ -205,7 +205,7 @@ def signedAssociationStringForThreepid(
             (medium, address, time_msec(), time_msec()),
         )
 
-        row = res.fetchone()
+        row: Optional[Tuple[str]] = res.fetchone()
 
         if not row:
             return None
@@ -233,7 +233,7 @@ def getMxid(self, medium: str, normalised_address: str) -> Optional[str]:
             (medium, normalised_address, time_msec(), time_msec()),
         )
 
-        row = res.fetchone()
+        row: Tuple[str] = res.fetchone()
 
         if not row:
             return None
@@ -352,7 +352,7 @@ def lastIdFromServer(self, server: str) -> Optional[int]:
             "where originServer = ?",
             (server,),
         )
-        row = res.fetchone()
+        row: Tuple[int, int] = res.fetchone()
 
         if row[1] == 0:
             return None

sydent/replication/peer.py

@@ -122,7 +122,7 @@ def __init__(
         server_name: str,
         port: Optional[int],
         pubkeys: Dict[str, str],
-        lastSentVersion: int,
+        lastSentVersion: Optional[int],
     ) -> None:
         """
         :param sydent: The current Sydent instance.

sydent/sydent.py

@@ -18,6 +18,7 @@
 import logging
 import logging.handlers
 import os
+import sqlite3
 from typing import Optional
 
 import twisted.internet.reactor
@@ -89,7 +90,7 @@ def __init__(
 
         logger.info("Starting Sydent server")
 
-        self.db = SqliteDatabase(self).db
+        self.db: sqlite3.Connection = SqliteDatabase(self).db
 
         if self.config.general.sentry_enabled:
             import sentry_sdk

sydent/threepid/__init__.py

@@ -11,6 +11,7 @@
 # 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 typing import Optional
 
 
 def threePidAssocFromDict(d):
@@ -36,7 +37,16 @@ def threePidAssocFromDict(d):
 
 
 class ThreepidAssociation:
-    def __init__(self, medium, address, lookup_hash, mxid, ts, not_before, not_after):
+    def __init__(
+        self,
+        medium: str,
+        address: str,
+        lookup_hash: Optional[str],
+        mxid: str,
+        ts: int,
+        not_before: int,
+        not_after: int,
+    ):
         """
         :param medium: The medium of the 3pid (eg. email)
         :param address: The identifier (eg. email address)

sydent/validators/__init__.py

@@ -11,6 +11,7 @@
 # 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 typing import Optional
 
 
 class ValidationSession:
@@ -22,14 +23,14 @@ class ValidationSession:
 
     def __init__(
         self,
-        _id,
-        _medium,
-        _address,
-        _clientSecret,
-        _validated,
-        _mtime,
-        _token,
-        _sendAttemptNumber,
+        _id: int,
+        _medium: str,
+        _address: str,
+        _clientSecret: str,
+        _validated: int,  # bool, but sqlite has no bool type
+        _mtime: int,
+        _token: Optional[str],
+        _sendAttemptNumber: Optional[int],
     ):
         self.id = _id
         self.medium = _medium