Comment faire en sorte que Mongoose liste tous les documents de la collection ? Pour savoir si la collection est vide ?

Je suppose que toutes les autres configurations requises pour la mangouste sont correctes.

À la ligne ci-dessous, je pense que 'myField' n'est pas nécessaire.

  this.model("Bids").find({}, 'myField', function(err, results)

Voici quelque chose de plus à partir de zéro, cela vous aiderait peut-être à retracer vos étapes :

 var mongoose = require('mongoose');

    //connection to Mongodb instance running on=======
    //local machine or anywhere=========================
    var uri = 'mongodb://localhost:27017/test';
    var connection = mongoose.createConnection(uri);


    //Define Schema==================================
    var Schema = mongoose.Schema;
    var BlogPostSchema = new Schema({
      author: { type: Schema.Types.ObjectId },
      title: String,
      body: String
    });


    //Create model===================================================
    var BlogPostModel = connection.model('BlogPost', BlogPostSchema);


    //function to insert doc into model NOTE "pass in your =======
    //callback or do away with it if you don't need one"=========
    var insertBlogPost = function (doc, callback) {
      
      //here is where or doc is converted to mongoose object
      var newblogPost = new BlogPostModel(doc); 
      
      //save to db
      newblogPost.save(function (err) {

        assert.equal(null, err);
        
        //invoke your call back if any
        callback();
        console.log("saved successfully");
      });
    };


    //function to get all BlogPosts====================================
    var getAllBlogPosts = function (callback) {

    //mongoose get all docs. I think here answers your question directly
      BlogPostModel.find(function (err, results) {
        assert.equal(null, err);
        
        //invoke callback with your mongoose returned result
        callback(results);
      });
    };


    //you can add as many functions as you need.

    //Put all of your methods in a single object interface 
    //and expose this object using module.

    var BlogPostManager = {
        insertBlogPost: insertBlogPost,
        getAllBlogPosts : getAllBlogPosts
    }


    module.exports = BlogPostManager;