ConnectionError [SequelizeConnectionError]：无法连接到：1433 - 无法连接（序列）本地机器 window 10

Question

***** mssql db connected sucessfully **** customers (node:116) [DEP0118] DeprecationWarning: The provided hostname "" is not a valid hostname, and is supported in the dns module solely for compatibility. (Use node --trace-deprecation... to show where the warning was created) ConnectionError [SequelizeConnectionError]: Failed to connect to:1433 - Could not connect (sequence) at ConnectionManager.connect (H:\codeoptimalsolutions\socialApp\backend\node_modules\sequelize\lib\dialects\mssql\connection-manager.js:139:17) at processTicksAndRejections (internal/process/task_queues.js:93:5) at async ConnectionManager._connect (H:\codeoptimalsolutions\socialApp\backend\node_modules\sequelize\lib\dialects\abstract\connection-manager.js:318:24) at async H:\codeoptimalsolutions\socialApp\backend\node_modules\sequelize\lib\dialects\abstract\connection-manager.js:250:32
at async ConnectionManager.getConnection (H:\codeoptimalsolutions\socialApp\backend\node_modules\sequelize\lib\dialects\abstract\connection-manager.js:280:7) at async H:\codeoptimalsolutions\socialApp\backend\node_modules\sequelize\lib\sequelize.js:613:26 at async MSSqlQueryInterface.select (H:\codeoptimalsolutions\socialApp\backend\node_modules\sequelize\lib\dialects\abstract\query-interface.js:953:12) at async Function.findAll (H:\codeoptimalsolutions\socialApp\backend\node_modules\sequelize\lib\model.js:1753:21) { parent: ConnectionError: Failed to connect to:1433 - Could not connect (sequence) at ConnectionError (H:\codeoptimalsolutions\socialApp\backend\node_modules\tedious\lib\errors.js:13:12) at Connection.socketError (H:\codeoptimalsolutions\socialApp\backend\node_modules\tedious\lib\connection.js:1641:56)
at H:\codeoptimalsolutions\socialApp\backend\node_modules\tedious\lib\connection.js:1400:21 at SequentialConnectionStrategy.connect (H:\codeoptimalsolutions\socialApp\backend\node_modules\tedious\lib\connector.js:129:14) at H:\codeoptimalsolutions\socialApp\backend\node_modules\tedious\lib\connector.js:201:80 at processTicksAndRejections (internal/process/task_queues.js:80:21) { code: 'ESOCKET' }, original: ConnectionError: Failed to connect to:1433 - Could not connect (sequence) at ConnectionError (H:\codeoptimalsolutions\socialApp\backend\node_modules\tedious\lib\errors.js:13:12) at Connection.socketError (H:\codeoptimalsolutions\socialApp\backend\node_modules\tedious\lib\connection.js:1641:56)
at H:\codeoptimalsolutions\socialApp\backend\node_modules\tedious\lib\connection.js:1400:21 at SequentialConnectionStrategy.connect (H:\codeoptimalsolutions\socialApp\backend\node_modules\tedious\lib\connector.js:129:14) at H:\codeoptimalsolutions\socialApp\backend\node_modules\tedious\lib\connector.js:201:80 at processTicksAndRejections (internal/process/task_queues.js:80:21) { code: 'ESOCKET' } }

I tried

1. TCP/IP is enabled

2. checked some answers ntng found all give me advice to enable TCP/IP

   var sequelize = new Sequelize(DBNAME,USERNAME,PASSWORD,{ dialect: 'mssql', host: hostname, port: 1433, logging: false, dialectOptions: { requestTimeout: 30000, encrypt: true } })

When i try to run get query then got this error

        Models.Customer.findAll({}, {}, {}).then(data=>{   
                      console.log(data);
          }).catch(err => { //console.log("err",err);
                      console.log(err);
          });

Answer 1

Bit of a stab in the dark because I don't feel there's enough information but the error states DeprecationWarning: The provided hostname "" is not a valid hostname, and is supported in the dns module solely for compatibility. Followed by a number of connection errors.

Your sequelize config contains:

   host: hostname,
  

So it looks to me as though "hostname" is returning an empty string but is necessary for the connection to proceed.

Edit to be a little more useful:

The sequelize documentation indicates that it defaults to localhost if not set , but here (I suspect) you are setting host name to an empty string. Try setting hostname explicitly to the database host and see if it connects.