Handle large proxy status responses

proxy_monitor_tui.py

@@ -22,6 +22,7 @@ DEFAULT_TIMEOUT_SECONDS = 10
 DEFAULT_TEST_URL = "https://www.gstatic.com/generate_204"
 DEFAULT_TEST_TIMEOUT_MS = 5000
 DEFAULT_DELAY_CONCURRENCY = 4
+MAX_JSON_RESPONSE_BYTES = 8 * 1024 * 1024
 
 
 class ApiError(RuntimeError):
@@ -154,7 +155,13 @@ class ProxyMonitorClient:
         )
         try:
             with urllib.request.urlopen(request, timeout=self.timeout_seconds) as response:
-                raw = response.read(1_048_576)
+                try:
+                    content_length = int(response.headers.get("Content-Length", "0"))
+                except ValueError:
+                    content_length = 0
+                if content_length > MAX_JSON_RESPONSE_BYTES:
+                    raise ApiError("response exceeds 8 MiB limit")
+                raw = response.read(MAX_JSON_RESPONSE_BYTES + 1)
         except urllib.error.HTTPError as exc:
             try:
                 detail = exc.read(1024).decode("utf-8", errors="replace").strip()
@@ -169,6 +176,8 @@ class ProxyMonitorClient:
 
         if not expect_json:
             return None
+        if len(raw) > MAX_JSON_RESPONSE_BYTES:
+            raise ApiError("response exceeds 8 MiB limit")
         if not raw:
             raise ApiError("response did not contain JSON")
         try:

pyproject.toml

@@ -1,6 +1,6 @@
 [project]
 name = "proxy-port-monitor-tui"
-version = "0.1.0"
+version = "0.1.1"
 description = "Terminal UI for proxy-port-monitor and mihomo selector groups"
 readme = "README.md"
 requires-python = ">=3.11"

tests/test_proxy_monitor_tui.py

@@ -23,6 +23,7 @@ def load_module():
 
 class ApiFixtureHandler(BaseHTTPRequestHandler):
     requests: list[dict[str, Any]] = []
+    large_status = False
 
     def _json(self, status: int, payload: object) -> None:
         body = json.dumps(payload).encode("utf-8")
@@ -36,7 +37,14 @@ class ApiFixtureHandler(BaseHTTPRequestHandler):
         parsed = urllib.parse.urlparse(self.path)
         type(self).requests.append({"method": "GET", "path": parsed.path, "query": urllib.parse.parse_qs(parsed.query)})
         if parsed.path == "/base/status.json":
-            self._json(200, {"targets_up": 1, "targets_total": 1, "targets": [{"name": "pc", "ok": True}]})
+            payload: dict[str, object] = {
+                "targets_up": 1,
+                "targets_total": 1,
+                "targets": [{"name": "pc", "ok": True}],
+            }
+            if type(self).large_status:
+                payload["padding"] = "x" * 1_100_000
+            self._json(200, payload)
             return
         if parsed.path == "/base/admin/pc%20win/api/proxies":
             self._json(
@@ -88,6 +96,7 @@ class ProxyMonitorTUITests(unittest.TestCase):
 
     def setUp(self) -> None:
         ApiFixtureHandler.requests = []
+        ApiFixtureHandler.large_status = False
         self.mod = load_module()
         self.base_url = f"http://127.0.0.1:{self.server.server_port}/base"
         self.client = self.mod.ProxyMonitorClient(self.base_url, 2)
@@ -124,6 +133,13 @@ class ProxyMonitorTUITests(unittest.TestCase):
             ],
         )
 
+    def test_status_response_larger_than_one_mebibyte_is_not_truncated(self) -> None:
+        ApiFixtureHandler.large_status = True
+
+        status = self.client.fetch_status()
+
+        self.assertEqual(len(status["padding"]), 1_100_000)
+
     def test_selector_groups_only_include_switchable_groups(self) -> None:
         groups = self.mod.normalize_selector_groups(
             {

uv.lock

@@ -63,7 +63,7 @@ wheels = [
 
 [[package]]
 name = "proxy-port-monitor-tui"
-version = "0.1.0"
+version = "0.1.1"
 source = { editable = "." }
 dependencies = [
     { name = "textual" },