Use psycopg connection pooling

poetry.lock

@@ -25,17 +25,17 @@ python-versions = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*"
 
 [[package]]
 name = "attrs"
-version = "21.4.0"
+version = "22.1.0"
 description = "Classes Without Boilerplate"
 category = "dev"
 optional = false
-python-versions = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*, !=3.4.*"
+python-versions = ">=3.5"
 
 [package.extras]
-dev = ["coverage[toml] (>=5.0.2)", "hypothesis", "pympler", "pytest (>=4.3.0)", "six", "mypy", "pytest-mypy-plugins", "zope.interface", "furo", "sphinx", "sphinx-notfound-page", "pre-commit", "cloudpickle"]
+dev = ["coverage[toml] (>=5.0.2)", "hypothesis", "pympler", "pytest (>=4.3.0)", "mypy (>=0.900,!=0.940)", "pytest-mypy-plugins", "zope.interface", "furo", "sphinx", "sphinx-notfound-page", "pre-commit", "cloudpickle"]
 docs = ["furo", "sphinx", "zope.interface", "sphinx-notfound-page"]
-tests = ["coverage[toml] (>=5.0.2)", "hypothesis", "pympler", "pytest (>=4.3.0)", "six", "mypy", "pytest-mypy-plugins", "zope.interface", "cloudpickle"]
-tests_no_zope = ["coverage[toml] (>=5.0.2)", "hypothesis", "pympler", "pytest (>=4.3.0)", "six", "mypy", "pytest-mypy-plugins", "cloudpickle"]
+tests = ["coverage[toml] (>=5.0.2)", "hypothesis", "pympler", "pytest (>=4.3.0)", "mypy (>=0.900,!=0.940)", "pytest-mypy-plugins", "zope.interface", "cloudpickle"]
+tests_no_zope = ["coverage[toml] (>=5.0.2)", "hypothesis", "pympler", "pytest (>=4.3.0)", "mypy (>=0.900,!=0.940)", "pytest-mypy-plugins", "cloudpickle"]
 
 [[package]]
 name = "black"
@@ -242,32 +242,41 @@ testing = ["pytest", "pytest-benchmark"]
 
 [[package]]
 name = "psycopg"
-version = "3.0.15"
+version = "3.0.16"
 description = "PostgreSQL database adapter for Python"
 category = "main"
 optional = false
 python-versions = ">=3.6"
 
 [package.dependencies]
-psycopg-c = {version = "3.0.15", optional = true, markers = "extra == \"c\""}
+psycopg-c = {version = "3.0.16", optional = true, markers = "extra == \"c\""}
+psycopg-pool = {version = "*", optional = true, markers = "extra == \"pool\""}
 tzdata = {version = "*", markers = "sys_platform == \"win32\""}
 
 [package.extras]
-binary = ["psycopg-binary (==3.0.15)"]
-c = ["psycopg-c (==3.0.15)"]
+binary = ["psycopg-binary (==3.0.16)"]
+c = ["psycopg-c (==3.0.16)"]
 dev = ["black (>=22.3.0)", "dnspython (>=2.1)", "flake8 (>=4.0)", "mypy (>=0.920,!=0.930,!=0.931)", "types-setuptools (>=57.4)", "wheel (>=0.37)"]
-docs = ["Sphinx (>=4.2)", "furo (==2021.11.23)", "sphinx-autobuild (>=2021.3.14)", "sphinx-autodoc-typehints (>=1.12)", "dnspython (>=2.1)", "shapely (>=1.7)"]
+docs = ["Sphinx (>=5.0)", "furo (==2022.6.21)", "sphinx-autobuild (>=2021.3.14)", "sphinx-autodoc-typehints (>=1.12)"]
 pool = ["psycopg-pool"]
 test = ["mypy (>=0.920,!=0.930,!=0.931)", "pproxy (>=2.7)", "pytest (>=6.2.5)", "pytest-asyncio (>=0.16,<0.17)", "pytest-cov (>=3.0)", "pytest-randomly (>=3.10)"]
 
 [[package]]
 name = "psycopg-c"
-version = "3.0.15"
+version = "3.0.16"
 description = "PostgreSQL database adapter for Python -- C optimisation distribution"
 category = "main"
 optional = false
 python-versions = ">=3.6"
 
+[[package]]
+name = "psycopg-pool"
+version = "3.1.1"
+description = "Connection Pool for Psycopg"
+category = "main"
+optional = false
+python-versions = ">=3.7"
+
 [[package]]
 name = "py"
 version = "1.11.0"
@@ -382,15 +391,12 @@ python-versions = ">=2"
 [metadata]
 lock-version = "1.1"
 python-versions = "^3.9"
-content-hash = "caaf302d6a55e9ff876fbcf8041aafb8c6b2a68369552e5a2d1aec847fd8251b"
+content-hash = "da053b15b994f3faa9d50bda1bfb459e64356cb2c9e06bad096cf57b67101894"
 
 [metadata.files]
 anyio = []
 atomicwrites = []
-attrs = [
-    {file = "attrs-21.4.0-py2.py3-none-any.whl", hash = "sha256:2d27e3784d7a565d36ab851fe94887c5eccd6a463168875832a1be79c82828b4"},
-    {file = "attrs-21.4.0.tar.gz", hash = "sha256:626ba8234211db98e869df76230a137c4c40a12d72445c45d5f5b716f076e2fd"},
-]
+attrs = []
 black = []
 certifi = []
 click = []
@@ -435,6 +441,7 @@ pluggy = [
 ]
 psycopg = []
 psycopg-c = []
+psycopg-pool = []
 py = [
     {file = "py-1.11.0-py2.py3-none-any.whl", hash = "sha256:607c53218732647dff4acdfcd50cb62615cedf612e72d1724fb1a0cc6405b378"},
     {file = "py-1.11.0.tar.gz", hash = "sha256:51c75c4126074b472f746a24399ad32f6053d1b34b68d2fa41e558e6f4a98719"},

pyproject.toml

@@ -13,7 +13,7 @@ httpx = "^0.18.2"
 parsy = "^1.3.0"
 jsonslicer = "^0.1.7"
 tqdm = "^4.64.0"
-psycopg = {extras = ["c"], version = "^3.0"}
+psycopg = {extras = ["c", "pool"], version = "^3.0"}
 
 [tool.poetry.dev-dependencies]
 pytest = "*"

tutor/cli.py

@@ -57,8 +57,8 @@ def main(ctx, database, log_level):
 @click.option("--debug", is_flag=True)
 @click.pass_context
 def server(ctx, port, scheme, static, debug):
-    app = tutor.server.make_app(
-        {
+    app = tutor.server.Application(
+        **{
             **ctx.obj,
             "scheme": scheme,
             "static": static,
@@ -134,7 +134,10 @@ def import_deck(ctx, filename, name):
                             )
                             if copies:
                                 await tutor.database.store_deck_card(
-                                    cursor, deck_id, copies[0].card.oracle_id, int(groups["quantity"])
+                                    cursor,
+                                    deck_id,
+                                    copies[0].card.oracle_id,
+                                    int(groups["quantity"]),
                                 )
             await conn.commit()
 

tutor/server.py

@@ -4,6 +4,8 @@ import typing
 import urllib.parse
 
 import psycopg
+import psycopg_pool
+import tornado.ioloop
 import tornado.web
 
 import tutor.database
@@ -56,7 +58,7 @@ class SearchHandler(tornado.web.RequestHandler):
         )
 
     async def get(self) -> None:
-        async with await psycopg.AsyncConnection.connect(self.application.settings["database"]) as conn:
+        async with self.application.pool.connection() as conn:
             async with conn.cursor() as cursor:
                 query = self.get_argument("q", "")
                 in_collection = self.get_argument("in_collection", None)
@@ -117,18 +119,23 @@ class SearchHandler(tornado.web.RequestHandler):
         )
 
 
-def make_app(settings) -> tornado.web.Application:
-    paths = [
-        (r"/search", SearchHandler),
-    ]
-    if static_path := settings.get("static"):
-        paths.extend(
-            [
-                (
-                    r"/(.*)",
-                    tornado.web.StaticFileHandler,
-                    {"path": static_path, "default_filename": "index.html"},
-                ),
-            ]
-        )
-    return tornado.web.Application(paths, **settings)
+class Application(tornado.web.Application):
+    def __init__(self, **settings):
+        paths = [
+            (r"/search", SearchHandler),
+        ]
+        if static_path := settings.get("static"):
+            paths.extend(
+                [
+                    (
+                        r"/(.*)",
+                        tornado.web.StaticFileHandler,
+                        {"path": static_path, "default_filename": "index.html"},
+                    ),
+                ]
+            )
+        tornado.ioloop.IOLoop.current().add_callback(self.async_init)
+        super().__init__(paths, **settings)
+
+    async def async_init(self):
+        self.pool = psycopg_pool.AsyncConnectionPool(self.settings["database"])