Add request timeout to pagination

README.md

@@ -4,6 +4,10 @@
 
 Welcome to the Hex Web Development Interview! During the interview session, you'll use this boilerplate repository to build out a frontend application with your interviewer. Before the session starts, please clone this repository and run `npm install` and `uv sync` in the root to install dependencies. You can also add any other dependencies that you think that you may want to use, but there is no need to write any code or do anything else ahead of time to prepare for the session.
 
+## Interview
+
+During the interview session, you'll implement two functions in this repository to fix an application. All changes will be made to [`api/pagination.py`](api/pagination.py).
+
 ## Running the app
 
 1) Install JS dependencies with `npm install`.

api/busy_loop_detector.py

@@ -0,0 +1,28 @@
+import time
+
+
+class BusyLoopDetector:
+    """
+    Detects busy loops by tracking the number of calls within a time window.
+    If the number of calls exceeds the threshold within the window, it raises
+    an error to prevent infinite loops from consuming resources.
+    """
+
+    def __init__(self, threshold: int = 1000, time_window: float = 1.0):
+        self._counter = 0
+        self._threshold = threshold
+        self._time_window = time_window
+        self._start_time = time.monotonic()
+
+    def _reset_timer(self) -> None:
+        self._start_time = time.monotonic()
+        self._counter = 0
+
+    def check(self) -> None:
+        self._counter += 1
+        current_time = time.monotonic()
+
+        if current_time - self._start_time > self._time_window:
+            self._reset_timer()
+        elif self._counter > self._threshold:
+            raise RuntimeError("Busy loop detected")

api/database.py

@@ -2,6 +2,7 @@
 import json
 from typing import List, Optional
 from models import Project
+from busy_loop_detector import BusyLoopDetector
 
 
 class ProjectDatabase:
@@ -11,6 +12,7 @@ def __init__(self):
             raw_data = json.load(f)
             # Convert raw dictionaries to Project objects
             self._items = [Project(**item) for item in raw_data]
+        self._detector = BusyLoopDetector()
 
     def get_items(
         self, page_size: int = 10, start_after: Optional[Project] = None
@@ -26,6 +28,8 @@ def get_items(
         Returns:
             List of Project objects for the requested page
         """
+        self._detector.check()
+
         if start_after is None:
             return self._items[:page_size]