Sequelize与Postgres的连接在ubuntu 18.04上被拒绝

我从win10 PC开发中将自己的nodejs 10.16.3应用程序部署到ubuntu 18.04。在ubuntu上使用pm2 start /ebs/myapp/index.js启动应用程序后，出现关于sequelize（5.19.1）数据库连接的错误：

$cat index-error.log
Unable to connect to the database: { SequelizeConnectionRefusedError: connect ECONNREFUSED 127.0.0.1:5433
    at connection.connect.err (/ebs/myapp/node_modules/sequelize/lib/dialects/postgres/connection-manager.js:170:24)
    at Connection.connectingErrorHandler (/ebs/myapp/node_modules/pg/lib/client.js:174:14)
    at Connection.emit (events.js:198:13)
    at Socket.reportStreamError (/ebs/myapp/node_modules/pg/lib/connection.js:72:10)
    at Socket.emit (events.js:198:13)
    at emitErrorNT (internal/streams/destroy.js:91:8)
    at emitErrorAndCloseNT (internal/streams/destroy.js:59:3)
    at process._tickCallback (internal/process/next_tick.js:63:19)
  name: 'SequelizeConnectionRefusedError',
  parent:
   { Error: connect ECONNREFUSED 127.0.0.1:5433
       at TCPConnectWrap.afterConnect [as oncomplete] (net.js:1106:14)
     errno: 'ECONNREFUSED',
     code: 'ECONNREFUSED',
     syscall: 'connect',
     address: '127.0.0.1',
     port: 5433 },
  original:
   { Error: connect ECONNREFUSED 127.0.0.1:5433
       at TCPConnectWrap.afterConnect [as oncomplete] (net.js:1106:14)
     errno: 'ECONNREFUSED',
     code: 'ECONNREFUSED',
     syscall: 'connect',
     address: '127.0.0.1',
     port: 5433 } }

postgres（11.5）在同一主机上运行，​​我可以通过命令行成功访问它。pm2日志文件还指示nodejs应用正在监听port 3000。此应用程序前端是nginx反向代理，可能与此错误无关。

这里是数据库连接字符串：

const Sql = require("sequelize");
const db = new Sql('mydb', 'postgres', `${process.env.DB_PASSWORD}`, {
    host: 'localhost',
    dialect: 'postgres',
    port:5433,
} );

为什么拒绝sequelize连接？

更新：PostgreSQL日志：

$ cat postgresql-11-main.log
2019-10-07 20:24:27.712 UTC [665] postgres@emps ERROR:  syntax error at or near "psql" at character 1
2019-10-07 20:24:27.712 UTC [665] postgres@emps STATEMENT:  psql
        ;
ubuntu@:/var/log/postgresql$ cat postgresql-11-main.log.1
2019-10-04 09:10:49.214 UTC [22809] LOG:  received fast shutdown request
2019-10-04 09:10:49.221 UTC [22809] LOG:  aborting any active transactions
2019-10-04 09:10:49.292 UTC [22809] LOG:  background worker "logical replication launcher" (PID 22816) exited with exit code 1
2019-10-04 09:10:49.298 UTC [22811] LOG:  shutting down
2019-10-04 09:10:49.435 UTC [22809] LOG:  database system is shut down
2019-10-04 09:11:11.561 UTC [1084] LOG:  listening on IPv4 address "127.0.0.1", port 5432
2019-10-04 09:11:11.567 UTC [1084] LOG:  listening on Unix socket "/var/run/postgresql/.s.PGSQL.5432"
2019-10-04 09:11:11.628 UTC [1096] LOG:  database system was shut down at 2019-10-04 09:10:49 UTC
2019-10-04 09:11:11.648 UTC [1084] LOG:  database system is ready to accept connections
2019-10-04 09:11:12.196 UTC [1134] [unknown]@[unknown] LOG:  incomplete startup packet
2019-10-04 09:11:17.827 UTC [1282] [unknown]@[unknown] LOG:  incomplete startup packet
2019-10-04 09:13:42.106 UTC [1084] LOG:  received fast shutdown request
2019-10-04 09:13:42.110 UTC [1084] LOG:  aborting any active transactions
2019-10-04 09:13:42.114 UTC [1084] LOG:  background worker "logical replication launcher" (PID 1102) exited with exit code 1
2019-10-04 09:13:42.115 UTC [1097] LOG:  shutting down
2019-10-04 09:13:42.138 UTC [1084] LOG:  database system is shut down
2019-10-04 09:13:46.533 UTC [3040] LOG:  listening on IPv4 address "127.0.0.1", port 5432
2019-10-04 09:13:46.535 UTC [3040] LOG:  listening on Unix socket "/var/run/postgresql/.s.PGSQL.5432"
2019-10-04 09:13:46.566 UTC [3041] LOG:  database system was shut down at 2019-10-04 09:13:42 UTC
2019-10-04 09:13:46.577 UTC [3040] LOG:  database system is ready to accept connections
2019-10-04 09:13:47.110 UTC [3048] [unknown]@[unknown] LOG:  incomplete startup packet
2019-10-04 09:13:52.713 UTC [3082] [unknown]@[unknown] LOG:  incomplete startup packet

您的PostgreSQL服务器的日志说它是在默认端口5432上启动的。但是在您的应用中，您尝试连接到5433。

改为尝试此连接：

const Sql = require("sequelize");
const db = new Sql('mydb', 'postgres', `${process.env.DB_PASSWORD}`, {
    host: 'localhost',
    dialect: 'postgres',
    port: 5432, // instead of 5433
} );