我正在尝试使用带有cassandra数据库的loopback 3框架从模型自动创建表，并且在连接datasource和cassandra datasource.json时遇到了一些问题

"cassandraConn": {
"host": "192.168.4.21",
"port": 9042,
"database": "emsv2_testing",
"password": "",
"name": "cassandraConn",
"user": "",
"connectTimeout": 30000,
"readTimeout": 30000,
"connector": "cassandra"
}

json模型file:-

{
"name": "data_rt_raw_t1",
"plural": "data_rt_raw_t1s",
"base": "PersistedModel",
"idInjection": true,
"options": {
"validateUpsert": true
},
"properties": {
"c_id": {
"type": "string",
"required": true,
"default": null
},
"slave_id": {
"type": "string",
"required": false,
"default": null
},
"dcu_id": {
"type": "string",
"required": false,
"default": null
},
"mfm_read_time": {
"type": "date",
"required": true,
"default": null
},
"data_store_time": {
"type": "date",
"required": false,
"default": null
},
"p1": {
"type": "number",
"required": false,
"default": null
},
"p2": {
"type": "number",
"required": false,
"default": null
},
"p3": {
"type": "number",
"required": false,
"default": null
},
"p4": {
"type": "number",
"required": false,
"default": null
},
"p5": {
"type": "number",
"required": false,
"default": null
}

},
"validations": [],
"relations": {},
"acls": [],
"methods": {}
}

自动迁移创建数据库名称“未定义”，在“未定义”数据库中创建表。尝试发布数据获取以下错误，

{
"error": {
"statusCode": 500,
"name": "NoHostAvailableError",
"message": "Connecting after shutdown is not supported",
"info": "Represents an error when a query cannot be performed because no host is available or could be reached by the driver.",
"innerErrors": null,
"stack": "NoHostAvailableError: Connecting after shutdown is not supported\n at Client._connectCb (/home/rd/enms/node_modules/cassandra-driver/lib/client.js:397:21)\n at Client.promiseWrapper (/home/rd/enms/node_modules/cassandra-driver/lib/utils.js:410:13)\n at Client.connect (/home/rd/enms/node_modules/cassandra-driver/lib/client.js:384:31)\n at Array.utils.series.next (/home/rd/enms/node_modules/cassandra-driver/lib/client.js:854:18)\n at next

帮我解决这个问题，谢谢。