chromium headless unikernel (#8)

* chromium headless unikernel

* updates

* test script

* move things around

* fix

* create inst

* create a kernel user and run chromium as that; hardcode chromium flags :/

kernel panic if the list of args is too long

```
[    0.023198] Kernel panic - not syncing: Too many boot init vars at `/usr/bin/wrapper.sh'
```

* cleanup

* update readme

* script to check memory usage of the unikraft instance

* lots of updates

* show network bytes

Author: rgarcia

shared/cdp-test/.gitignore

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+screenshot.png
+screenshot-before.png

shared/cdp-test/.python-version

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+3.11

shared/cdp-test/main.py

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+import sys
+import asyncio
+import json
+import re
+import socket
+from pathlib import Path
+from urllib.parse import urljoin, urlparse
+from urllib.request import urlopen, Request
+from playwright.async_api import async_playwright, TimeoutError as PlaywrightTimeoutError  # type: ignore
+import aiohttp  # type: ignore
+import contextlib
+
+async def run(cdp_url: str) -> None:
+    """Connect to an existing Chromium instance via CDP, navigate, and screenshot."""
+    async with async_playwright() as p:
+        # Connect to the running browser exposed via the CDP websocket URL.
+        browser = await p.chromium.connect_over_cdp(cdp_url)
+
+        # Re-use the first context if present, otherwise create a fresh one.
+        if browser.contexts:
+            context = browser.contexts[0]
+        else:
+            context = await browser.new_context()
+
+        # Re-use the first page if present, otherwise create a fresh one.
+        page = context.pages[0] if context.pages else await context.new_page()
+
+        # Snapshot the page as-is for debugging purposes.
+        print(f"Page URL: {page.url}")
+        print(f"Taking screenshot before navigation")
+        await page.screenshot(path="screenshot-before.png", full_page=True)
+
+        # Decide destination URL.
+        target_url = (
+            "https://www.apple.com"
+            if "apple.com" not in page.url
+            else "https://www.microsoft.com"
+        )
+
+        print(f"Navigating to {target_url} …", file=sys.stderr)
+
+        try:
+            # First wait only for DOMContentLoaded – many modern sites keep long-polling
+            # connections alive which makes the stricter "networkidle" heuristic unreliable.
+            await page.goto(target_url, wait_until="domcontentloaded", timeout=60_000)
+
+            # Optionally wait for a quieter network but don't fail if it never settles.
+            try:
+                await page.wait_for_load_state("networkidle", timeout=10_000)
+            except PlaywrightTimeoutError:
+                print("networkidle state not reached within 10 s – proceeding", file=sys.stderr)
+
+        except PlaywrightTimeoutError:
+            print(f"Navigation to {target_url} timed out after 60 s", file=sys.stderr)
+            # Capture the state for post-mortem analysis.
+            await page.screenshot(path="screenshot-error.png", full_page=True)
+            raise
+
+        # Ensure output directory and save screenshot.
+        out_path = Path("screenshot.png")
+        await page.screenshot(path=str(out_path), full_page=True)
+        print(f"Screenshot saved to {out_path.resolve()}")
+
+        await browser.close()
+
+
+# ---------------- CLI entrypoint ---------------- #
+
+def _resolve_cdp_url(arg: str) -> str:
+    """Resolve the provided argument to a CDP websocket URL.
+
+    If *arg* already looks like a ws:// or wss:// URL, return it unchanged.
+    Otherwise, treat it as a DevTools HTTP endpoint (e.g. http://localhost:9222
+    or just localhost:9222), fetch /json/version, and extract the
+    'webSocketDebuggerUrl'.
+    """
+
+    # Ensure scheme. Default to http:// if none supplied.
+    if not arg.startswith(("http://", "https://")):
+        arg = f"http://{arg}"
+
+    version_url = urljoin(arg.rstrip("/") + "/", "json/version")
+    try:
+
+        # Chromium devtools HTTP server only accepts Host headers that are an
+        # IP literal or "localhost".  If the caller passed a hostname, resolve
+        # it to an IP so that the request is not rejected.
+        parsed = urlparse(version_url)
+        raw_host = parsed.hostname or "localhost"
+        # Quick-and-dirty IP-literal check (IPv4 or bracket-less IPv6).
+        _IP_RE = re.compile(r"^(?:\d+\.\d+\.\d+\.\d+|[0-9a-fA-F:]+)$")
+        if raw_host != "localhost" and not _IP_RE.match(raw_host):
+            try:
+                raw_host = socket.gethostbyname(raw_host)
+            except Exception:  # noqa: BLE001
+                # Fall back to localhost if resolution fails; devtools handler
+                # will at least accept it rather than closing the connection.
+                raw_host = "localhost"
+        host_header = raw_host
+        if parsed.port:
+            host_header = f"{host_header}:{parsed.port}"
+        print(f"Host header: {host_header}")
+        req = Request(version_url, headers={"Host": host_header})
+        with urlopen(req) as resp:
+            data = json.load(resp)
+        print(f"Data: {data}")
+        # change ws:// to ws:// if parsed was https. Also change IP back to the hostname
+        if parsed.scheme == "https":
+            data["webSocketDebuggerUrl"] = data["webSocketDebuggerUrl"].replace("ws://", "wss://")
+            data["webSocketDebuggerUrl"] = data["webSocketDebuggerUrl"].replace(raw_host, parsed.hostname)
+        print(f"debugger url: {data['webSocketDebuggerUrl']}")
+        return data["webSocketDebuggerUrl"]
+    except Exception as exc:  # noqa: BLE001
+        print(
+            f"Failed to retrieve webSocketDebuggerUrl from {version_url}: {exc}",
+            file=sys.stderr,
+        )
+        sys.exit(1)
+
+# ---------------- keep-alive task ---------------- #
+
+
+async def _keep_alive(endpoint: str) -> None:
+    """Periodically send a GET request to *endpoint* to keep the instance alive."""
+    # Ensure scheme; default to http:// if missing.
+    if not endpoint.startswith(("http://", "https://")):
+        endpoint = f"http://{endpoint}"
+
+    async with aiohttp.ClientSession() as session:
+        while True:
+            try:
+                async with session.get(endpoint) as resp:
+                    # Consume the response body to finish the request.
+                    await resp.read()
+            except Exception as exc:  # noqa: BLE001
+                print(f"Keep-alive request to {endpoint} failed: {exc}", file=sys.stderr)
+
+            await asyncio.sleep(1)
+
+
+async def _async_main(endpoint_arg: str) -> None:
+    """Resolve CDP URL, start keep-alive task, and run the browser automation."""
+
+    cdp_url = _resolve_cdp_url(endpoint_arg)
+
+    # Start the keep-alive loop.
+    keep_alive_task = asyncio.create_task(_keep_alive(endpoint_arg))
+
+    try:
+        await run(cdp_url)
+    finally:
+        # Ensure the keep-alive task is cancelled cleanly when run() completes.
+        keep_alive_task.cancel()
+        with contextlib.suppress(asyncio.CancelledError):
+            await keep_alive_task
+
+def main() -> None:
+    if len(sys.argv) < 2:
+        print("Usage: python main.py <DevTools HTTP endpoint>", file=sys.stderr)
+        sys.exit(1)
+    asyncio.run(_async_main(sys.argv[1]))
+
+if __name__ == "__main__":
+    main()

shared/cdp-test/pyproject.toml

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+[project]
+name = "cdp-test"
+version = "0.1.0"
+description = "Add your description here"
+readme = "README.md"
+requires-python = ">=3.11"
+dependencies = [
+    "aiohttp>=3.12.13",
+    "playwright>=1.52.0",
+]