strict typecheck db module, basic typecheck for the rest

.gitignore

@@ -1,2 +1,3 @@
 __pycache__
 /.env
+/node_modules

README.md

@@ -26,11 +26,13 @@ Prerequisites:
 * [Google Cloud SDK](https://cloud.google.com/sdk/docs/install)
 * [jq](https://stedolan.github.io/jq/)
 * Aiven project with Kafka and Postgres running
+* npm
 
 Setup:
 ```
 poetry env use python3.9
 poetry install
+npm install
 ```
 
 Load Aiven credentials and service URIs to `.env/` (replace `pg-123456` and `kafka-123456` with correct service names in Aiven):

lint

@@ -3,6 +3,8 @@ set -eux
 
 SOURCES=(sitewatch tests)
 
+npm run typecheck
+
 # stop the build if there are Python syntax errors or undefined names
 poetry run flake8 sitewatch --count --select=E9,F63,F7,F82 --show-source --statistics
 # exit-zero treats all errors as warnings. The GitHub editor is 127 chars wide

package.json

@@ -0,0 +1,10 @@
+{
+  "name": "sitewatch",
+  "scripts": {
+    "typecheck": "pyright",
+    "typecheck-watch": "pyright -w"
+  },
+  "dependencies": {
+    "pyright": "^1.1.97"
+  }
+}

pyproject.toml

@@ -21,6 +21,7 @@ pytest = "^6.2.1"
 snapshottest = "^0.6.0"
 black = "^20.8b1"
 pytest-trio = "^0.7.0"
+trio-typing = "^0.5.0"
 
 [build-system]
 requires = ["poetry-core>=1.0.0"]

pyrightconfig.json

@@ -0,0 +1,8 @@
+{
+  "include": [
+    "sitewatch"
+  ],
+  "pythonVersion": "3.9",
+  "venvPath": ".",
+  "venv": ".venv"
+}

sitewatch/db.py

@@ -1,13 +1,16 @@
 """Datatabase connection, tables init and main operations"""
 
+# pyright: strict
+
 import os
 from datetime import timedelta
 import re
-from typing import List
+from typing import List, Any
 from contextlib import asynccontextmanager
 
 import trio
 import triopg
+from triopg import Connection
 
 from .model import Report, Page
 
@@ -25,7 +28,7 @@ def connect():
 
 
 @asynccontextmanager
-async def listen(conn, channel):
+async def listen(conn: Connection, channel: str):
     """LISTEN on `channel` notifications and return memory channel to iterate over
 
     For example:
@@ -37,9 +40,9 @@ async def listen(conn, channel):
 
     # based on https://gitter.im/python-trio/general?at=5fe10d762084ee4b78650fc8
 
-    send_channel, receive_channel = trio.open_memory_channel(1)
+    send_channel, receive_channel = trio.open_memory_channel[str](1)
 
-    def _listen_callback(c, pid, chan, payload):
+    def _listen_callback(c: Any, pid: Any, chan: str, payload: str):
         send_channel.send_nowait(payload)
 
     await conn.add_listener(channel, _listen_callback)
@@ -48,7 +51,7 @@ def _listen_callback(c, pid, chan, payload):
     await conn.remove_listener(channel, _listen_callback)
 
 
-async def init_page_table(conn):
+async def init_page_table(conn: Connection):
     """Initialize `page` table and add fixtures (idempotent)"""
 
     await conn.execute(
@@ -104,7 +107,7 @@ async def init_page_table(conn):
     )
 
 
-async def init_report_table(conn):
+async def init_report_table(conn: Connection):
     """Initialize `report` table (idempotent)"""
 
     await conn.execute(
@@ -121,7 +124,7 @@ async def init_report_table(conn):
     )
 
 
-async def fetch_pages(conn) -> List[Page]:
+async def fetch_pages(conn: Connection) -> List[Page]:
     pages = [
         Page(
             row['pageid'],
@@ -135,7 +138,7 @@ async def fetch_pages(conn) -> List[Page]:
     return pages
 
 
-async def save_report(conn, r: Report):
+async def save_report(conn: Connection, r: Report):
     await conn.execute(
         '''
         INSERT INTO report(pageid, elapsed, statuscode, sent, found)

sitewatch/model.py

@@ -1,6 +1,6 @@
 from typing import Optional
 from dataclasses import dataclass
-from datetime import timedelta, datetime
+from datetime import timedelta
 import json
 import re
 
@@ -21,11 +21,11 @@ class Page:
 class Report(typesystem.Schema):
     """Web page check result"""
 
-    pageid: int = typesystem.Integer(minimum=0)
-    sent: datetime = typesystem.DateTime()
-    elapsed: float = typesystem.Float(minimum=0)
-    status_code: int = typesystem.Integer()
-    found: Optional[bool] = typesystem.Boolean(default=None, allow_null=True)
+    pageid = typesystem.Integer(minimum=0)
+    sent = typesystem.DateTime()
+    elapsed = typesystem.Float(minimum=0)
+    status_code = typesystem.Integer()
+    found = typesystem.Boolean(default=None, allow_null=True)
 
     def tobytes(self) -> bytes:
         """Serialize to JSON"""
@@ -35,3 +35,6 @@ def tobytes(self) -> bytes:
     def frombytes(cls, raw: bytes) -> 'Report':
         """Deserialize from JSON"""
         return typesystem.validate_json(raw, validator=Report)
+
+
+__all__ = ["Page", "Report", "ValidationError", "ParseError"]

typings/triopg/__init__.pyi

@@ -0,0 +1,10 @@
+"""
+This type stub file was generated by pyright.
+"""
+
+from ._triopg import connect, create_pool, TrioConnectionProxy as Connection
+from .exceptions import *
+
+"""
+This type stub file was generated by pyright.
+"""