Node.js 连接在查询完成之前终止

Newbie with node.js.
I have set up an Node/express server on a Windows Server hosting a PostgreSQL database.
My goal is to insert in the database the data from a csv file choosen by a user on its own computer, using a HTML form.

以下是用户提交表单后执行的js文件的一部分:

app.post('/envoi', upload.single("fichiercsv"), async(req, res) => {
let newClient
try {
    const { identifiant, motdepasse } = req.body
    const clientConfigModifie = {
    ...clientConfigDefaut,
    user: identifiant,
    password: ''
    }
    newClient = new Client(clientConfigModifie)
        
    await newClient.connect()
     
    const rows = []
    const buffer = req.file.buffer
        // console.log(buffer) //ok
    const readableStreamFromBuffer = new stream.Readable()
    readableStreamFromBuffer.push(req.file.buffer)
    readableStreamFromBuffer.push(null)
    await new Promise( (resolve, reject) => {
        fastcsv.parseStream(readableStreamFromBuffer, { headers: false })
            .on('data', us => {
                rows.push(us)   
            })
            .on('end', async() => { 
                rows.shift()
                const usTotal = rows.map( us => us.join("").split(";"))
                // console.log(us)
                for (const us of usTotal) {
                await newClient.query("insert into activite.us (numus, gidgeo) VALUES ($1, $2)", [us[0], us[13]])
                })
                resolve()
            })
            .on("error", error => console.error(error))
        })  
}   
catch(e) {
    console.log("erreur lors du traitement", e)
    res.send(`<h3>échec de la connexion</h3>`)
}
finally {
    try {
        newClient.end()
    }
    catch(e) { 
        console.log(e) 
    }
}
})

• 如果省略finally部分，数据将插入到数据库中，但连接仍在运行...
• 对于finally零件，只插入us的第first行.因此，我得到了这样的信息:

error: Connection terminated at C:\Apache\balbla\个

In this case, it seems that newClient.query runs one time only then for some reason the connection is terminated but not ended.
What am I doing wrong ?

EDIT:@I2yscho回答后更新代码.