Mongoose populate（）返回空数组

我想通过clientSchema中的属性'token'来查询子文档数组。 但我无法填充子文档数组。 它总是返回空值。

这是我的尝试

var performAuthAsync = promise.promisify(performAuth); var response = {}; performAuthAsync(req).then(function (client) { sendStatus(res, 200, { "success": "true", "value": client }); }).catch(ApiError, function (e) { response.error = "true"; response.message = e.message; if (e.message == "Invalid Authorization" || e.message == "Unauthorized access") { console.log(e.message); sendStatus(res, 401, response, req.query.type); } else { sendStatus(res, 500, response, req.query.type); } }); 

PerformAuth方法

 function performAuth(req, callback) { try { var authHeader = req.headers.authorization; console.log(authHeader); //error in req format if (!authHeader || !authHeader.startsWith("Basic ")) { console.log("inside fail authheader"); return callback(new ApiError("Invalid Authorization")); } authHeader = authHeader.replace("Basic ", ""); authHeader = Buffer.from(authHeader, 'base64').toString('ascii'); console.log(authHeader); //temporary populate check clientApp.findOne({}).populate({ path: 'appClients', model: 'TClient' }).exec(function (error, apps) { console.log("populated apps check " + apps); //object containing empty array //{ _id: 5987099f2cb916a0de80f067, // appSecret: 'THisIsSecret', // appId: 'W5ikGw16dQjgWm8bGjqdAwi1IDR2XibD3XESYokH', // appClients: [] } // mongo console output // { "_id" : ObjectId ("5987099f2cb916a0de80f067"), // "appSecret" : "THisIsSecret", // "appId" : "W5ikGw16dQjgWm8bGjqdAwi1IDR2XibD3XESYokH", // "appClients" : [ ObjectId("59881a64dbab536016e7f970") ], "__v" : 0 } }); clientApp.findOne({}).populate('appClients').findOne({ 'appClients.token': authHeader }).exec(function (error, client) { if (error) { console.log("inside dberror"); console.error(error); return callback(error, null); } if (!client) { return callback(new ApiError("Unauthorized access"), null); } return callback(client); }); } catch (exception) { console.log("inside exception"); console.error(exception); return callback(exception, null); } } 

客户端应用程序和客户端模式:(它们在不同的文件中）

 var appSchema = new Schema({ appId: { type: String, required: true, unique: true }, appSecret: { type: String, required: true, unique: true }, appClients: [{ type: Schema.Types.ObjectId, ref: 'TClient' }], createdAt: Date, modifiedAt: Date }); // model var clientApp = mongoose.model('ClientApp', appSchema); var clientSchema = new Schema({ clientId: { type: String, required: true, unique: true }, info: { type: String, required: true, }, token: { type: String, required: true, unique: true }, createdAt: Date, modifiedAt: Date }); // model var tclient = mongoose.model('TClient', clientSchema); 

我做错了什么？ 任何帮助表示赞赏