curl --request POST \
  --url 'https://api.flashcat.cloud/channel/subscribe/rule/list?app_key=' \
  --header 'Content-Type: application/json' \
  --data '
{
  "channel_id": 123
}
'

{
  "error": {
    "code": "<string>",
    "message": "<string>"
  },
  "data": {
    "items": [
      {
        "channel_id": 123,
        "rule_id": "<string>",
        "rule_name": "<string>",
        "description": "<string>",
        "filters": [
          [
            {
              "key": "title",
              "oper": "IN",
              "vals": [
                "<string>"
              ]
            }
          ]
        ],
        "status": "enabled",
        "created_at": "<string>",
        "updated_at": "<string>",
        "updated_by": 123
      }
    ]
  }
}