Initial Playwright setup plus first test

Refs #2779

.github/workflows/playwright.yml

@@ -0,0 +1,48 @@
+name: Playwright
+
+on:
+  push:
+  pull_request:
+  workflow_dispatch:
+
+permissions:
+  contents: read
+
+jobs:
+  test:
+    runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        browser: [chromium, firefox, webkit]
+    steps:
+    - uses: actions/checkout@v6
+    - name: Set up Python 3.14
+      uses: actions/setup-python@v6
+      with:
+        python-version: "3.14"
+        allow-prereleases: true
+        cache: pip
+        cache-dependency-path: pyproject.toml
+    - name: Cache uv
+      uses: actions/cache@v5
+      with:
+        path: ~/.cache/uv
+        key: ${{ runner.os }}-py3.14-uv-${{ hashFiles('pyproject.toml') }}
+        restore-keys: |
+          ${{ runner.os }}-py3.14-uv-
+    - name: Cache Playwright browsers
+      uses: actions/cache@v5
+      with:
+        path: ~/.cache/ms-playwright/
+        key: ${{ runner.os }}-playwright-${{ matrix.browser }}-${{ hashFiles('pyproject.toml') }}
+        restore-keys: |
+          ${{ runner.os }}-playwright-${{ matrix.browser }}-
+    - name: Install uv
+      run: python -m pip install uv
+    - name: Install dependencies
+      run: uv sync --group dev --group playwright
+    - name: Install ${{ matrix.browser }}
+      run: uv run --group dev --group playwright playwright install --with-deps ${{ matrix.browser }}
+    - name: Run Playwright tests
+      run: uv run --group dev --group playwright pytest tests/test_playwright.py --playwright --browser ${{ matrix.browser }}

pyproject.toml

@@ -81,6 +81,9 @@ dev = [
     "ruamel.yaml",
     "psutil>=5.9",
 ]
+playwright = [
+    "pytest-playwright>=0.8.0",
+]
 
 [project.optional-dependencies]
 rich = ["rich"]

pytest.ini

@@ -6,4 +6,5 @@ filterwarnings=
     ignore:Using or importing the ABCs::bs4.element
 markers =
     serial: tests to avoid using with pytest-xdist
-asyncio_mode = strict
+    playwright: browser automation tests, skipped unless --playwright is passed
+asyncio_mode = strict

tests/conftest.py

@@ -96,6 +96,15 @@ def pytest_report_header(config):
     return "SQLite: {}".format(version)
 
 
+def pytest_addoption(parser):
+    parser.addoption(
+        "--playwright",
+        action="store_true",
+        default=False,
+        help="run Playwright browser automation tests",
+    )
+
+
 def pytest_configure(config):
     import sys
 
@@ -108,7 +117,13 @@ def pytest_unconfigure(config):
     del sys._called_from_test
 
 
-def pytest_collection_modifyitems(items):
+def pytest_collection_modifyitems(config, items):
+    if not config.getoption("--playwright"):
+        skip_playwright = pytest.mark.skip(reason="need --playwright option to run")
+        for item in items:
+            if "playwright" in item.keywords:
+                item.add_marker(skip_playwright)
+
     # Ensure test_cli.py and test_black.py and test_inspect.py run first before any asyncio code kicks in
     move_to_front(items, "test_cli")
     move_to_front(items, "test_black")

tests/test_playwright.py

@@ -0,0 +1,79 @@
+import socket
+import subprocess
+import sys
+import time
+
+import httpx
+import pytest
+
+from datasette.fixtures import write_fixture_database
+
+
+def find_free_port():
+    with socket.socket() as sock:
+        sock.bind(("127.0.0.1", 0))
+        return sock.getsockname()[1]
+
+
+def wait_for_server(process, url, timeout=10):
+    deadline = time.monotonic() + timeout
+    last_error = None
+    while time.monotonic() < deadline:
+        if process.poll() is not None:
+            stdout, stderr = process.communicate()
+            raise AssertionError(
+                "Datasette server exited early\n"
+                f"stdout:\n{stdout}\n"
+                f"stderr:\n{stderr}"
+            )
+        try:
+            response = httpx.get(url, timeout=1.0)
+            if response.status_code < 500:
+                return
+            last_error = f"HTTP {response.status_code}: {response.text[:200]}"
+        except httpx.HTTPError as ex:
+            last_error = repr(ex)
+        time.sleep(0.1)
+    raise AssertionError(f"Timed out waiting for {url}: {last_error}")
+
+
+@pytest.fixture
+def datasette_server(tmp_path):
+    db_path = tmp_path / "fixtures.db"
+    write_fixture_database(str(db_path))
+    port = find_free_port()
+    process = subprocess.Popen(
+        [
+            sys.executable,
+            "-m",
+            "datasette",
+            str(db_path),
+            "--host",
+            "127.0.0.1",
+            "--port",
+            str(port),
+            "--setting",
+            "num_sql_threads",
+            "1",
+        ],
+        stdout=subprocess.PIPE,
+        stderr=subprocess.PIPE,
+        text=True,
+    )
+    url = f"http://127.0.0.1:{port}/"
+    try:
+        wait_for_server(process, url)
+        yield url
+    finally:
+        process.terminate()
+        try:
+            process.wait(timeout=5)
+        except subprocess.TimeoutExpired:
+            process.kill()
+            process.wait()
+
+
+@pytest.mark.playwright
+def test_datasette_homepage_contains_datasette(page, datasette_server):
+    page.goto(datasette_server)
+    assert "Datasette" in page.locator("body").inner_text()