Nodejsmongodb動的コレクション名

db.collection（'name'）。find（{}）

これが私が試したコードです
App.js

const express = require('express');
const bodyParser = require('body-parser');

const MongoClient = require("mongodb").MongoClient;
const assert = require('assert');
const url = 'mongodb://localhost:27017';
var db;

MongoClient.connect(url, { useNewUrlParser: true }, function (err, client) {
assert.equal(null, err);
console.log("Connected successfully to DB");
db = client.db('name of the db');
});

var app=express();

app.use(bodyParser.json());
app.use(bodyParser.urlencoded({ extended: false }));

app.get('/test/:collection', function(req,res){
let collection = req.params.collection;
console.log(collection);
db.collection(collection).find({}).toArray( function (err, result) {
    res.send(result);
    });
});

var port = 8000
app.listen(port, '0.0.0.0', () => {
    console.log('Service running on port ' + port);
});

これがお役に立てば幸いです