{
  "id": "python/flask-session-modification-error",
  "signature": "RuntimeError: The session is unavailable because no secret key was set.",
  "signature_zh": "运行时错误：会话不可用，因为未设置密钥。",
  "regex": "RuntimeError:\\ The\\ session\\ is\\ unavailable\\ because\\ no\\ secret\\ key\\ was\\ set\\.",
  "domain": "python",
  "category": "runtime_error",
  "subcategory": null,
  "root_cause": "Flask requires a secret_key to use sessions, which is not set.",
  "root_cause_type": "generic",
  "root_cause_zh": "Flask需要使用secret_key来使用会话，但未设置。",
  "versions": [
    {
      "version": "3.x",
      "introduced": null,
      "deprecated": null,
      "removed": null,
      "behavior_change": null,
      "status": "active"
    }
  ],
  "os_specific": {},
  "dead_ends": [
    {
      "action": "Setting secret_key to an empty string.",
      "why_fails": "An empty string is not a valid secret key; Flask will still raise an error.",
      "fail_rate": 0.8,
      "condition": "",
      "sources": []
    },
    {
      "action": "Using secret_key after the first request without setting it before.",
      "why_fails": "Secret key must be set before the first request; setting it later has no effect.",
      "fail_rate": 0.7,
      "condition": "",
      "sources": []
    }
  ],
  "workarounds": [
    {
      "action": "Set a secret key in the Flask app configuration.",
      "success_rate": 0.95,
      "how": "app.secret_key = 'your-secret-key'",
      "condition": "",
      "sources": []
    },
    {
      "action": "Use environment variables for security.",
      "success_rate": 0.9,
      "how": "import os\napp.secret_key = os.environ.get('SECRET_KEY', 'fallback-key')",
      "condition": "",
      "sources": []
    }
  ],
  "workarounds_zh": [],
  "transition_graph": {
    "leads_to": [],
    "preceded_by": [],
    "frequently_confused_with": []
  },
  "official_doc_url": null,
  "official_doc_section": null,
  "error_code": null,
  "verification_tier": "ai_generated",
  "confidence": 0.85,
  "fix_success_rate": 0.8,
  "resolvable": "true",
  "first_seen": "2024-10-05",
  "last_confirmed": "2025-01-01",
  "last_updated": "2025-01-01",
  "evidence_count": 0,
  "tags": [],
  "locale": "en",
  "aliases": []
}