45 lines
1.4 KiB
Python
45 lines
1.4 KiB
Python
#!/usr/bin/env python3
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"""Concurrency-bounded threaded HTTP server for the Hermes SCM broker."""
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from __future__ import annotations
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import threading
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from http.server import ThreadingHTTPServer
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MAX_CONCURRENT_REQUESTS = 2
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class BoundedThreadingHTTPServer(ThreadingHTTPServer):
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"""Cap active handlers so large Git exchanges cannot exhaust memory."""
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daemon_threads = True
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block_on_close = True
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request_queue_size = 16
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def __init__(self, *args, **kwargs):
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self._slots = threading.BoundedSemaphore(MAX_CONCURRENT_REQUESTS)
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super().__init__(*args, **kwargs)
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def process_request(self, request, client_address) -> None:
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if not self._slots.acquire(blocking=False):
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try:
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request.sendall(
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b"HTTP/1.1 503 Service Unavailable\r\n"
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b"Connection: close\r\nContent-Length: 0\r\n\r\n"
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)
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finally:
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self.shutdown_request(request)
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return
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try:
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super().process_request(request, client_address)
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except Exception:
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self._slots.release()
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self.shutdown_request(request)
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raise
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def process_request_thread(self, request, client_address) -> None:
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try:
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super().process_request_thread(request, client_address)
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finally:
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self._slots.release()
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