test: cover the validator, the directory and the site

tests/conftest.py

@@ -0,0 +1,143 @@
+"""Shared fixtures: fixture paths, a temporary database, and a local web server."""
+
+from http.server import BaseHTTPRequestHandler, ThreadingHTTPServer
+from pathlib import Path
+import threading
+
+import pytest
+
+from mews import db
+
+ROOT = Path(__file__).resolve().parent.parent
+FIXTURES = Path(__file__).resolve().parent / "fixtures"
+
+
+@pytest.fixture
+def fail_page():
+    """Read one of the non-conforming fixture pages."""
+
+    def read(name: str) -> bytes:
+        return (FIXTURES / "fail" / f"{name}.html").read_bytes()
+
+    return read
+
+
+@pytest.fixture
+def connection(tmp_path):
+    """An empty database."""
+    handle = db.connect(str(tmp_path / "mews.db"))
+    db.init(handle)
+    yield handle
+    handle.close()
+
+
+class Site:
+    """A web server on loopback whose responses the test writes."""
+
+    def __init__(self) -> None:
+        self.routes: dict[str, tuple[int, dict[str, str], bytes, bool]] = {}
+        self.requests: list[tuple[str, dict[str, str]]] = []
+        self.delay = 0.0
+        self._server = ThreadingHTTPServer(("127.0.0.1", 0), _handler(self))
+        self._thread = threading.Thread(target=self._server.serve_forever, daemon=True)
+        self._thread.start()
+
+    @property
+    def base(self) -> str:
+        """The address the server answers on."""
+        host, port = self._server.server_address[:2]
+        return f"http://{host}:{port}"
+
+    def add(
+        self,
+        path: str,
+        body: bytes = b"",
+        status: int = 200,
+        headers: dict[str, str] | None = None,
+        declare_length: bool = True,
+    ) -> str:
+        """Serve body at path, and return its full address.
+
+        With declare_length off the response carries no Content-Length and ends
+        at the connection close, which is how a streaming body reaches the
+        fetcher's byte cap.
+        """
+        self.routes[path] = (status, headers or {}, body, declare_length)
+        return self.base + path
+
+    def close(self) -> None:
+        """Stop the server."""
+        self._server.shutdown()
+        self._server.server_close()
+
+
+def _handler(site: "Site"):
+    class Handler(BaseHTTPRequestHandler):
+        protocol_version = "HTTP/1.1"
+
+        def do_GET(self):
+            import time
+
+            site.requests.append((self.path, dict(self.headers)))
+            if site.delay:
+                time.sleep(site.delay)
+            status, headers, body, declare_length = site.routes.get(
+                self.path, (404, {}, b"not here", True)
+            )
+            if not declare_length:
+                self.protocol_version = "HTTP/1.0"
+                self.close_connection = True
+            self.send_response(status)
+            for name, value in headers.items():
+                self.send_header(name, value)
+            if "Content-Type" not in headers and status == 200:
+                self.send_header("Content-Type", "text/html; charset=utf-8")
+            if declare_length:
+                self.send_header("Content-Length", str(len(body)))
+            self.end_headers()
+            if body:
+                self.wfile.write(body)
+
+        def log_message(self, *args):
+            pass
+
+        def handle_one_request(self):
+            try:
+                super().handle_one_request()
+            except (BrokenPipeError, ConnectionResetError):
+                self.close_connection = True
+
+    return Handler
+
+
+@pytest.fixture
+def site():
+    """A local web server for the checks that need a live page."""
+    server = Site()
+    yield server
+    server.close()
+
+
+@pytest.fixture
+def conforming():
+    """A page that follows the spec, with a stylesheet link the test can point."""
+
+    def build(stylesheet: str = "mews-0.1.css", body: str = "<p>Hello.</p>") -> bytes:
+        return f"""<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE html PUBLIC "-//WAPFORUM//DTD XHTML Mobile 1.2//EN"
+  "http://www.openmobilealliance.org/tech/DTD/xhtml-mobile12.dtd">
+<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
+  <head>
+    <title>Test site</title>
+    <meta name="mews-profile" content="0.1" />
+    <meta name="viewport" content="width=device-width" />
+    <meta name="description" content="A test page." />
+    <link rel="stylesheet" type="text/css" href="{stylesheet}" />
+  </head>
+  <body>
+    {body}
+  </body>
+</html>
+""".encode()
+
+    return build