Node.js gridfs流和猫鼬>；=4.11.0连接设置

我一直在将gridfs stream与旧版本一起使用（我发现了一个解决方案，该解决方案使用了deasync，并且对我现有的所有代码进行了最小的更改。但是，它看起来并不理想，因此任何建议都将非常感谢：

    var grid = require("gridfs-stream");
    var mongoose = require("mongoose");
    var deasync = require("deasync");

    //Connect to mongodb
    mongoose.Promise = global.Promise;
    mongoose.connect(connectionString, {useMongoClient: true});

    //Get the connection setting
    var getConnDb = function () {
        var connDb;
        mongoose.connection.then(function (conn) {
            connDb = conn.db;
        });
        while (connDb === undefined) {
            deasync.runLoopOnce();
        }
        return connDb;
    };

    //Set gridfs-stream connection
    grid.mongo = db.mongo;
    var gfs = grid(getConnDb());

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谢谢你的回答。事实上，现在connection.db只有在建立连接后才被设置。你不必强制使用deasync，因为你可以使用它：

mongoose.connect（connectionString，{useMongoClient:true}）。然后（（mongoInstance）=>{connDb=mongoInstance.connection.db}）

    mongoose.connect(connectionString, {useMongoClient: true});

    var grid = require("gridfs-stream");
    var mongoose = require("mongoose");
    var deasync = require("deasync");

    //Connect to mongodb
    mongoose.Promise = global.Promise;
    mongoose.connect(connectionString, {useMongoClient: true});

    //Get the connection setting
    var getConnDb = function () {
        var connDb;
        mongoose.connection.then(function (conn) {
            connDb = conn.db;
        });
        while (connDb === undefined) {
            deasync.runLoopOnce();
        }
        return connDb;
    };

    //Set gridfs-stream connection
    grid.mongo = db.mongo;
    var gfs = grid(getConnDb());