使用nodejs程序连接时出现错误：connect ECONNREFUSED 127.0.0.1:5432

Question

我在 CentOS 8 机器上设置了一个 postgresql 服务器，并使用该pg库在同一台机器上运行一个 js 程序。

const { Pool } = require('pg')

const pool = new Pool({
    user: process.env.PG_USER,      //postgres user
    host: process.env.PG_ENDPOINT,  //localhost (I also tried 127.0.0.1)
    database: process.env.PG_DB,    //database name to connect to
    password: process.env.PG_PASS,  //postgres user password
    port: process.env.PG_PORT       //5432
});

我正确设置了 pg 池，如果我想将其连接到我的 AWS postgres 服务器（当然，具有正确的端点等），它工作得很好，但是当我尝试让它连接到 postgres 服务器时，我在同一台机器上设置时，出现以下错误：

Error: connect ECONNREFUSED 127.0.0.1:5432
    at TCPConnectWrap.afterConnect [as oncomplete] (net.js:1146:16) {
  errno: -111,
  code: 'ECONNREFUSED',
  syscall: 'connect',
  address: '127.0.0.1',
  port: 5432
}

我按照说明设置 pg_hba.conf 文件以允许密码登录而不是 ident：

# "local" is for Unix domain socket connections only
local   all             all                                     peer
# IPv4 local connections:
host    all             all             127.0.0.1/32            ident
host    all             all             127.0.0.1/32            md5
# IPv6 local connections:
host    all             all             ::1/128                 ident
host    all             all             ::1/128                 md5

# Allow replication connections from localhost, by a user with the
# replication privilege.
local   replication     all                                     peer
host    replication     all             127.0.0.1/32            ident
host    replication     all             127.0.0.1/32            md5
host    replication     all             ::1/128                 ident
host    replication     all             ::1/128                 md5

在 postgresql.conf 中，我取消注释了listen_addresses和port行：

# - Connection Settings -

listen_addresses = 'localhost'          # what IP address(es) to listen on;
                                        # comma-separated list of addresses;
                                        # defaults to 'localhost'; use '*' for all
                                        # (change requires restart)
port = 5432                             # (change requires restart)
max_connections = 100                   # (change requires restart)
#superuser_reserved_connections = 3     # (change requires restart)
#unix_socket_directories = '/var/run/postgresql, /tmp'  # comma-separated list of directories

任何帮助表示赞赏。

netstat -na 的结果：

Proto Recv-Q Send-Q Local Address           Foreign Address         State
tcp        0      0 0.0.0.0:22              0.0.0.0:*               LISTEN
tcp        0      0 ###.##.43.124:22        ###.##.122.136:59611   ESTABLISHED
tcp        0     64 ###.##.43.124:22        ###.##.122.136:59445   ESTABLISHED
tcp6       0      0 :::22                   :::*                    LISTEN
udp        0      0 127.0.0.1:323           0.0.0.0:*
udp        0      0 0.0.0.0:68              0.0.0.0:*
udp6       0      0 ::1:323                 :::*
raw6       0      0 :::58                   :::*                    7

(#用于隐藏IP)

Answer 1

没有netstat显示在 5432 处监听的任何内容，这是您告诉 PostgreSQL 监听的位置。如果它没有在监听，您就无法连接到它。为什么它不听？也许它没有运行——您应该检查它的日志文件并看看发生了什么。