{"library":"priority","title":"HTTP/2 Priority Tree","description":"Priority is a pure-Python implementation of the HTTP/2 priority logic, as described in RFC 7540 Section 5.3 (Stream Priority). It allows clients to express preferences for how servers allocate resources across concurrent HTTP/2 requests by managing a priority tree. The library uses a variant of the implementation from the H2O project. The current version, 2.0.0, was released in June 2021, indicating a stable project in maintenance mode, part of the broader python-hyper ecosystem for HTTP/2 related libraries.","language":"python","status":"maintenance","last_verified":"Wed May 13","install":{"commands":["pip install priority"],"cli":null},"imports":["from priority import PriorityTree"],"auth":{"required":false,"env_vars":[]},"quickstart":{"code":"import priority\n\np = priority.PriorityTree()\np.insert_stream(stream_id=1)\np.insert_stream(stream_id=3)\np.insert_stream(stream_id=5, depends_on=1)\np.insert_stream(stream_id=7, weight=32)\np.insert_stream(stream_id=9, depends_on=7, weight=8)\np.insert_stream(stream_id=11, depends_on=7, exclusive=True)\n\n# Simulate sending data by iterating the tree\nprint(\"Initial serving order:\")\nfor _ in range(10):\n    next_stream_id = p.next_stream_to_send()\n    if next_stream_id is None:\n        print(\"  No more active streams.\")\n        break\n    print(f\"  Sending data for stream: {next_stream_id}\")\n    # Simulate blocking a stream after it's been served once\n    if next_stream_id == 7:\n        p.block(7)\n        print(\"  Stream 7 blocked for demonstration.\")\n    \n# Unblock a stream to see it re-enter the queue\np.unblock(7)\nprint(\"\\nStream 7 unblocked. Continuing serving order:\")\nfor _ in range(5):\n    next_stream_id = p.next_stream_to_send()\n    if next_stream_id is None:\n        print(\"  No more active streams.\")\n        break\n    print(f\"  Sending data for stream: {next_stream_id}\")","lang":"python","description":"Initialize a `PriorityTree`, insert streams with various dependencies and weights, then iterate using `next_stream_to_send()` to determine the optimal sending order. 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