Forward SSH port in Node.js

ssh2-client.ts

import sshClient from 'ssh2-promise'

const config = {
  database: {
    host: process.env.DB_HOST,
    username: process.env.DB_USER,
    password: process.env.DB_PASSWORD,
    port: process.env.DB_PORT,
    databaseName: process.env.DB_NAME,
  },
  ssh: {
    host: process.env.SSH_HOST,
    port: process.env.SSH_PORT,
    identity: process.env.SSH_KEY_PATH,
    // username: process.env.SSH_USER,
    // password: process.env.SSH_PASSWORD,
  }
}

export const connectSHHTunnel = async (): Promise<void> => {
    const ssh = new sshClient(config.ssh)

    // connect tunnel
    try {
        await ssh.connect()

        console.log(`SSH connection established to ${config.ssh.host}:${config.ssh.port}`)
    } catch (error) {
        console.error('[ssh.connect]', error)
    }

    // forward local port
    try {
      await ssh.addTunnel({
        remoteAddr: config.database.host,
        remotePort: Number(config.database.port),
        localPort: Number(config.database.port)
      })

      console.log(`Remote ${config.database.host}:${config.database.port} forwarded to localhost:${config.database.port}`)

    } catch(error) {
      console.error('[ssh.addTunnel]', error)
    } 

    ssh.on('close', async() => {
      console.log('client disconnected by server. Reconnecting...')
      
      await connectSHHTunnel()
    })
}