ref(update): Adding caching to checking for latest version (#179)

* ref(update): Adding caching to checking for latest version * Adding more test coverage * Switching to a simpler caching approach * Using constant in test
getsentry · Dec 13, 2024 · 2af25a6 · 2af25a6
1 parent 1a86f18
commit 2af25a6
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Showing 7 changed files with 243 additions and 17 deletions.
diff --git a/devservices/commands/check_for_update.py b/devservices/commands/check_for_update.py
diff --git a/devservices/commands/update.py b/devservices/commands/update.py
@@ -7,10 +7,10 @@
 from argparse import Namespace
 from importlib import metadata
 
-from devservices.commands.check_for_update import check_for_update
 from devservices.constants import DEVSERVICES_DOWNLOAD_URL
 from devservices.exceptions import BinaryInstallError
 from devservices.exceptions import DevservicesUpdateError
+from devservices.utils.check_for_update import check_for_update
 from devservices.utils.console import Console
 from devservices.utils.install_binary import install_binary
 

diff --git a/devservices/constants.py b/devservices/constants.py
@@ -1,6 +1,7 @@
 from __future__ import annotations
 
 import os
+from datetime import timedelta
 
 MINIMUM_DOCKER_COMPOSE_VERSION = "2.29.7"
 DEVSERVICES_DIR_NAME = "devservices"
@@ -11,8 +12,8 @@
 DEVSERVICES_LOCAL_DIR = os.path.expanduser("~/.local/share/sentry-devservices")
 DEVSERVICES_DEPENDENCIES_CACHE_DIR = os.path.join(DEVSERVICES_CACHE_DIR, "dependencies")
 DEVSERVICES_DEPENDENCIES_CACHE_DIR_KEY = "DEVSERVICES_DEPENDENCIES_CACHE_DIR"
-DEVSERVICES_ORCHESTRATOR_LABEL = "orchestrator=devservices"
 STATE_DB_FILE = os.path.join(DEVSERVICES_LOCAL_DIR, "state")
+DEVSERVICES_ORCHESTRATOR_LABEL = "orchestrator=devservices"
 DOCKER_COMPOSE_COMMAND_LENGTH = 7
 
 DEPENDENCY_CONFIG_VERSION = "v1"
@@ -22,9 +23,18 @@
     "core.sparseCheckout": "true",
 }
 
+DEVSERVICES_RELEASES_URL = (
+    "https://api.github.com/repos/getsentry/devservices/releases/latest"
+)
 DOCKER_COMPOSE_DOWNLOAD_URL = "https://github.com/docker/compose/releases/download"
 DEVSERVICES_DOWNLOAD_URL = "https://github.com/getsentry/devservices/releases/download"
 BINARY_PERMISSIONS = 0o755
 MAX_LOG_LINES = "100"
 LOGGER_NAME = "devservices"
 DOCKER_NETWORK_NAME = "devservices"
+
+# Latest Version Cache
+DEVSERVICES_LATEST_VERSION_CACHE_FILE = os.path.join(
+    DEVSERVICES_CACHE_DIR, "latest_version.txt"
+)
+DEVSERVICES_LATEST_VERSION_CACHE_TTL = timedelta(minutes=15)
diff --git a/devservices/main.py b/devservices/main.py
@@ -23,10 +23,10 @@
 from devservices.commands import status
 from devservices.commands import up
 from devservices.commands import update
-from devservices.commands.check_for_update import check_for_update
 from devservices.constants import LOGGER_NAME
 from devservices.exceptions import DockerComposeInstallationError
 from devservices.exceptions import DockerDaemonNotRunningError
+from devservices.utils.check_for_update import check_for_update
 from devservices.utils.console import Console
 from devservices.utils.docker_compose import check_docker_compose_version
 

diff --git a/devservices/utils/check_for_update.py b/devservices/utils/check_for_update.py
@@ -0,0 +1,59 @@
+from __future__ import annotations
+
+import json
+import os
+from datetime import datetime
+from datetime import timedelta
+from urllib.request import urlopen
+
+from devservices.constants import DEVSERVICES_CACHE_DIR
+from devservices.constants import DEVSERVICES_LATEST_VERSION_CACHE_FILE
+from devservices.constants import DEVSERVICES_LATEST_VERSION_CACHE_TTL
+from devservices.constants import DEVSERVICES_RELEASES_URL
+
+
+def _delete_cached_version() -> None:
+    if os.path.exists(DEVSERVICES_LATEST_VERSION_CACHE_FILE):
+        os.remove(DEVSERVICES_LATEST_VERSION_CACHE_FILE)
+
+
+def _get_cache_age() -> timedelta:
+    if os.path.exists(DEVSERVICES_LATEST_VERSION_CACHE_FILE):
+        file_modification_time = datetime.fromtimestamp(
+            os.path.getmtime(DEVSERVICES_LATEST_VERSION_CACHE_FILE)
+        )
+        return datetime.now() - file_modification_time
+    return timedelta.max
+
+
+def _get_cached_version() -> str | None:
+    cache_age = _get_cache_age()
+    if cache_age < DEVSERVICES_LATEST_VERSION_CACHE_TTL:
+        with open(DEVSERVICES_LATEST_VERSION_CACHE_FILE, "r", encoding="utf-8") as f:
+            return f.read()
+    else:
+        _delete_cached_version()
+        return None
+
+
+def _set_cached_version(latest_version: str) -> None:
+    with open(DEVSERVICES_LATEST_VERSION_CACHE_FILE, "w", encoding="utf-8") as f:
+        f.write(latest_version)
+
+
+def check_for_update() -> str | None:
+    os.makedirs(DEVSERVICES_CACHE_DIR, exist_ok=True)
+
+    cached_version = _get_cached_version()
+    if cached_version is not None:
+        return cached_version
+
+    with urlopen(DEVSERVICES_RELEASES_URL) as response:
+        if response.status == 200:
+            data = json.loads(response.read())
+            latest_version = str(data["tag_name"])
+
+            _set_cached_version(latest_version)
+
+            return latest_version
+    return None
diff --git a/requirements-dev.txt b/requirements-dev.txt
@@ -8,3 +8,4 @@ types-PyYAML==6.0.11
 setuptools==70.0.0
 build==0.8.0
 wheel==0.42.0
+freezegun==1.2.2
diff --git a/tests/utils/test_check_for_update.py b/tests/utils/test_check_for_update.py
@@ -0,0 +1,170 @@
+from __future__ import annotations
+
+from datetime import datetime
+from datetime import timedelta
+from pathlib import Path
+from unittest import mock
+
+from freezegun import freeze_time
+
+from devservices.constants import DEVSERVICES_LATEST_VERSION_CACHE_TTL
+from devservices.constants import DEVSERVICES_RELEASES_URL
+from devservices.utils.check_for_update import check_for_update
+
+
+@mock.patch("devservices.utils.check_for_update.urlopen")
+def test_check_for_update_not_cached(mock_urlopen: mock.Mock, tmp_path: Path) -> None:
+    mock_response = mock.mock_open(read_data=b'{"tag_name": "1.0.0"}').return_value
+    mock_response.status = 200
+    mock_urlopen.side_effect = [mock_response]
+    cache_dir = tmp_path / "cache"
+    cached_file = cache_dir / "latest_version.txt"
+    with (
+        freeze_time("2024-05-14 05:43:21"),
+        mock.patch(
+            "devservices.utils.check_for_update.os.path.getmtime",
+            return_value=datetime.now().timestamp(),
+        ),
+        mock.patch(
+            "devservices.utils.check_for_update.DEVSERVICES_CACHE_DIR",
+            str(cache_dir),
+        ),
+        mock.patch(
+            "devservices.utils.check_for_update.DEVSERVICES_LATEST_VERSION_CACHE_FILE",
+            str(cached_file),
+        ),
+    ):
+        assert check_for_update() == "1.0.0"
+        mock_urlopen.assert_called_once_with(DEVSERVICES_RELEASES_URL)
+
+        with cached_file.open("r") as f:
+            cached_version = f.read()
+            assert cached_version == "1.0.0"
+
+
+@mock.patch("devservices.utils.check_for_update.urlopen")
+def test_check_for_update_no_cache_not_ok(
+    mock_urlopen: mock.Mock, tmp_path: Path
+) -> None:
+    mock_response = mock.mock_open().return_value
+    mock_response.status = 500
+    mock_urlopen.side_effect = [mock_response]
+    cache_dir = tmp_path / "cache"
+    cached_file = cache_dir / "latest_version.txt"
+    with (
+        mock.patch(
+            "devservices.utils.check_for_update.DEVSERVICES_CACHE_DIR",
+            str(cache_dir),
+        ),
+        mock.patch(
+            "devservices.utils.check_for_update.DEVSERVICES_LATEST_VERSION_CACHE_FILE",
+            str(cached_file),
+        ),
+    ):
+        assert check_for_update() is None
+        mock_urlopen.assert_called_once_with(DEVSERVICES_RELEASES_URL)
+
+        assert not cached_file.exists()
+
+
+@mock.patch("devservices.utils.check_for_update.urlopen")
+def test_check_for_update_cached_fresh(mock_urlopen: mock.Mock, tmp_path: Path) -> None:
+    cache_dir = tmp_path / "cache"
+    cached_file = cache_dir / "latest_version.txt"
+    with (
+        freeze_time("2024-05-14 05:43:21"),
+        mock.patch(
+            "devservices.utils.check_for_update.os.path.getmtime",
+            return_value=(
+                datetime.now()
+                - DEVSERVICES_LATEST_VERSION_CACHE_TTL
+                + timedelta(minutes=1)
+            ).timestamp(),
+        ),
+        mock.patch(
+            "devservices.utils.check_for_update.DEVSERVICES_CACHE_DIR",
+            str(cache_dir),
+        ),
+        mock.patch(
+            "devservices.utils.check_for_update.DEVSERVICES_LATEST_VERSION_CACHE_FILE",
+            str(cached_file),
+        ),
+    ):
+        cache_dir.mkdir()
+        cached_file.write_text("1.0.0")
+        assert check_for_update() == "1.0.0"
+        mock_urlopen.assert_not_called()
+
+
+@mock.patch("devservices.utils.check_for_update.urlopen")
+def test_check_for_update_cached_stale_without_update(
+    mock_urlopen: mock.Mock, tmp_path: Path
+) -> None:
+    mock_response = mock.mock_open(read_data=b'{"tag_name": "1.0.0"}').return_value
+    mock_response.status = 200
+    mock_urlopen.side_effect = [mock_response]
+    cache_dir = tmp_path / "cache"
+    cached_file = cache_dir / "latest_version.txt"
+    with (
+        freeze_time("2024-05-14 05:43:21"),
+        mock.patch(
+            "devservices.utils.check_for_update.os.path.getmtime",
+            return_value=(
+                datetime.now() - DEVSERVICES_LATEST_VERSION_CACHE_TTL
+            ).timestamp(),
+        ),
+        mock.patch(
+            "devservices.utils.check_for_update.DEVSERVICES_CACHE_DIR",
+            str(cache_dir),
+        ),
+        mock.patch(
+            "devservices.utils.check_for_update.DEVSERVICES_LATEST_VERSION_CACHE_FILE",
+            str(cached_file),
+        ),
+    ):
+        cache_dir.mkdir()
+        cached_file.write_text("1.0.0")
+        assert check_for_update() == "1.0.0"
+        mock_urlopen.assert_called_once_with(DEVSERVICES_RELEASES_URL)
+
+        with cached_file.open("r") as f:
+            cached_version = f.read()
+            assert cached_version == "1.0.0"
+
+
+@mock.patch("devservices.utils.check_for_update.urlopen")
+def test_check_for_update_cached_stale_with_update(
+    mock_urlopen: mock.Mock, tmp_path: Path
+) -> None:
+    mock_response = mock.mock_open(read_data=b'{"tag_name": "1.0.1"}').return_value
+    mock_response.status = 200
+    mock_urlopen.side_effect = [mock_response]
+    cache_dir = tmp_path / "cache"
+    cached_file = cache_dir / "latest_version.txt"
+    with (
+        freeze_time("2024-05-14 05:43:21"),
+        mock.patch(
+            "devservices.utils.check_for_update.os.path.getmtime",
+            return_value=(
+                datetime.now()
+                - DEVSERVICES_LATEST_VERSION_CACHE_TTL
+                - timedelta(minutes=1)
+            ).timestamp(),
+        ),
+        mock.patch(
+            "devservices.utils.check_for_update.DEVSERVICES_CACHE_DIR",
+            str(cache_dir),
+        ),
+        mock.patch(
+            "devservices.utils.check_for_update.DEVSERVICES_LATEST_VERSION_CACHE_FILE",
+            str(cached_file),
+        ),
+    ):
+        cache_dir.mkdir()
+        cached_file.write_text("1.0.0")
+        assert check_for_update() == "1.0.1"
+        mock_urlopen.assert_called_once_with(DEVSERVICES_RELEASES_URL)
+
+        with cached_file.open("r") as f:
+            cached_data = f.read()
+            assert cached_data == "1.0.1"