Route computer and playwright calls directly to the VM

Add computer and playwright to the default browser routing allowlist
so screenshot and execute traffic can skip the control plane once
metro-api records activity on the kernel proxy.

Author: tnsardesai

src/kernel/lib/browser_routing/routing.py

@@ -44,7 +44,7 @@ def browser_routing_config_from_env() -> BrowserRoutingConfig:
         # Path prefixes eligible for direct-to-VM routing. "telemetry/stream" is
         # the live SSE endpoint (VM); "telemetry/events" is a historical read
         # served by the control plane (S2) and must NOT be here.
-        return BrowserRoutingConfig(subresources=("curl", "telemetry/stream"))
+        return BrowserRoutingConfig(subresources=("curl", "telemetry/stream", "computer", "playwright"))
     if raw.strip() == "":
         return BrowserRoutingConfig()
 

tests/test_browser_routing.py

@@ -392,7 +392,12 @@ def test_browser_route_from_browser_requires_base_url_and_jwt() -> None:
 
 def test_browser_routing_config_from_env_defaults_to_curl(monkeypatch: pytest.MonkeyPatch) -> None:
     monkeypatch.delenv("KERNEL_BROWSER_ROUTING_SUBRESOURCES", raising=False)
-    assert browser_routing_config_from_env().subresources == ("curl", "telemetry/stream")
+    assert browser_routing_config_from_env().subresources == (
+        "curl",
+        "telemetry/stream",
+        "computer",
+        "playwright",
+    )
 
 
 def test_direct_vm_routing_allowlist_segment_boundary() -> None:
@@ -401,13 +406,16 @@ def test_direct_vm_routing_allowlist_segment_boundary() -> None:
     # stream-prefixed-but-different path is not matched.
     from kernel.lib.browser_routing.routing import _matches_direct_vm_prefix
 
-    prefixes = ("curl", "telemetry/stream")
+    prefixes = ("curl", "telemetry/stream", "computer", "playwright")
     assert _matches_direct_vm_prefix("telemetry/stream", prefixes) is True
     assert _matches_direct_vm_prefix("telemetry/stream/x", prefixes) is True
     assert _matches_direct_vm_prefix("telemetry/events", prefixes) is False
     assert _matches_direct_vm_prefix("telemetry/streaming-config", prefixes) is False
     assert _matches_direct_vm_prefix("telemetry", prefixes) is False
     assert _matches_direct_vm_prefix("curl/raw", prefixes) is True
+    assert _matches_direct_vm_prefix("computer/screenshot", prefixes) is True
+    assert _matches_direct_vm_prefix("playwright/execute", prefixes) is True
+    assert _matches_direct_vm_prefix("process/exec", prefixes) is False
     assert _matches_direct_vm_prefix("fs/read", prefixes) is False
 
 
@@ -427,7 +435,7 @@ def test_rewrite_direct_vm_options_keeps_telemetry_events_on_control_plane() ->
     cache.set(
         BrowserRoute(session_id="sess-1", base_url="http://browser-session.test/browser/kernel", jwt="token-abc")
     )
-    config = BrowserRoutingConfig(subresources=("curl", "telemetry/stream"))
+    config = BrowserRoutingConfig(subresources=("curl", "telemetry/stream", "computer", "playwright"))
 
     events = rewrite_direct_vm_options(
         FinalRequestOptions(method="get", url="/browsers/sess-1/telemetry/events"), cache=cache, config=config
@@ -439,7 +447,79 @@ def test_rewrite_direct_vm_options_keeps_telemetry_events_on_control_plane() ->
     )
     assert str(stream.url).startswith("http://browser-session.test/browser/kernel/telemetry/stream")
 
+    screenshot = rewrite_direct_vm_options(
+        FinalRequestOptions(method="post", url="/browsers/sess-1/computer/screenshot"), cache=cache, config=config
+    )
+    assert str(screenshot.url).startswith("http://browser-session.test/browser/kernel/computer/screenshot")
+
+    execute = rewrite_direct_vm_options(
+        FinalRequestOptions(method="post", url="/browsers/sess-1/playwright/execute"), cache=cache, config=config
+    )
+    assert str(execute.url).startswith("http://browser-session.test/browser/kernel/playwright/execute")
+
+    process = rewrite_direct_vm_options(
+        FinalRequestOptions(method="post", url="/browsers/sess-1/process/exec"), cache=cache, config=config
+    )
+    assert process.url == "/browsers/sess-1/process/exec"
+
+    fs_read = rewrite_direct_vm_options(
+        FinalRequestOptions(method="get", url="/browsers/sess-1/fs/read_file"), cache=cache, config=config
+    )
+    assert fs_read.url == "/browsers/sess-1/fs/read_file"
+
 
 def test_browser_routing_config_from_env_empty_string_disables_routing(monkeypatch: pytest.MonkeyPatch) -> None:
     monkeypatch.setenv("KERNEL_BROWSER_ROUTING_SUBRESOURCES", "")
     assert browser_routing_config_from_env().subresources == ()
+
+
+@respx.mock
+def test_computer_screenshot_and_playwright_execute_route_to_vm_by_default(
+    monkeypatch: pytest.MonkeyPatch,
+) -> None:
+    monkeypatch.delenv("KERNEL_BROWSER_ROUTING_SUBRESOURCES", raising=False)
+    screenshot = respx.post("http://browser-session.test/browser/kernel/computer/screenshot").mock(
+        return_value=httpx.Response(200, content=b"png", headers={"content-type": "image/png"})
+    )
+    execute = respx.post("http://browser-session.test/browser/kernel/playwright/execute").mock(
+        return_value=httpx.Response(200, json={"success": True})
+    )
+    with Kernel(base_url=base_url, api_key=api_key, _strict_response_validation=True) as client:
+        _cache_browser(client)
+        client.browsers.computer.capture_screenshot("sess-1")
+        out = client.browsers.playwright.execute("sess-1", code="return 1")
+
+    assert screenshot.called
+    screenshot_req = cast(httpx.Request, cast(Any, screenshot.calls[0]).request)
+    assert screenshot_req.url.params.get("jwt") == "token-abc"
+    assert screenshot_req.headers.get("Authorization") is None
+    assert execute.called
+    execute_req = cast(httpx.Request, cast(Any, execute.calls[0]).request)
+    assert execute_req.url.params.get("jwt") == "token-abc"
+    assert execute_req.headers.get("Authorization") is None
+    assert out.success is True
+
+
+@respx.mock
+def test_process_fs_and_telemetry_events_stay_on_api_origin_by_default(
+    monkeypatch: pytest.MonkeyPatch,
+) -> None:
+    monkeypatch.delenv("KERNEL_BROWSER_ROUTING_SUBRESOURCES", raising=False)
+    process = respx.post(f"{base_url}/browsers/sess-1/process/exec").mock(
+        return_value=httpx.Response(200, json={"exit_code": 0, "stdout_b64": "", "stderr_b64": ""})
+    )
+    fs_read = respx.get(f"{base_url}/browsers/sess-1/fs/read_file").mock(
+        return_value=httpx.Response(200, content=b"x", headers={"content-type": "application/octet-stream"})
+    )
+    events = respx.get(f"{base_url}/browsers/sess-1/telemetry/events").mock(
+        return_value=httpx.Response(200, json=[])
+    )
+    with Kernel(base_url=base_url, api_key=api_key, _strict_response_validation=True) as client:
+        _cache_browser(client)
+        client.browsers.process.exec("sess-1", command="echo")
+        client.browsers.fs.read_file("sess-1", path="/tmp/x")
+        client.browsers.telemetry.events("sess-1")
+
+    assert process.called
+    assert fs_read.called
+    assert events.called