im_message

{
    "id": 0,
    "speaker": "string",
    "speakerType": "User",
    "speakerName": "string",
    "audience": "string",
    "audienceType": "User",
    "audienceName": "string",
    "time": 0,
    "msgType": "text",
    "msgContent": "string"
}