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JavaScript

Posted by Bruno Navarrete
.a{fill-rule:evenodd;}techdegree seal-36
Bruno Navarrete
Full Stack JavaScript Techdegree Graduate 22,246 Points

Can't log Animal.find() query results.

I can't find a reason why this isn't working, nothing inside the .find() callback works (not even the logging of 'hello') :(

    Animal.remove({},(err) => { // remove every Animal document, add query to remove specific ones
        if(err) console.error(err);
        elephant.save((err) => { // both the collection AND the (elephant) document will be saved now, not before
            if(err) console.error(err);
            animal.save((err) => { // Inside callback so that all animals are saved before db.close()
                if(err) console.error(err);
                whale.save((err) => { // Inside callback so that all animals are saved before db.close()
                    if(err) console.error(err);
                    Animal.find({size:'big'},(err,animals) => {
                        animals.forEach(( animal ) => {
                            console.log(animal.name + ' the ' + animal.color + ' ' +animal.type);
                        });
                        console.log('hello');
                    });
                    db.close(() => { // Inside callback since .close() is asynchronous
                        console.log('db connection closed');
                    }); 
                });
            });
        });
    });

1 Answer

Bruno Navarrete
.a{fill-rule:evenodd;}techdegree seal-36
Bruno Navarrete
Full Stack JavaScript Techdegree Graduate 22,246 Points

I'm sorry, I thought I was in the video's forum section. This is for the Default Values in Mongoose video and I already solved it. It turns out I was closing the db outside of the Animal.find()'s callback, so it closed before it (the callback) could run. The correct code would be:

Animal.find({size:'big'},(err,animals) => {
    animals.forEach(( animal ) => {
         console.log(animal.name + ' the ' + animal.color + ' ' +animal.type); 
    });
    db.close(() => { // Inside callback since .close() is asynchronous
         console.log('db connection closed');
    });
});
Bruno Navarrete
.a{fill-rule:evenodd;}techdegree seal-36
Bruno Navarrete
Full Stack JavaScript Techdegree Graduate 22,246 Points

Here's my full code for reference:

'use strict';

var mongoose = require('mongoose');
mongoose.connect('mongodb://localhost:27017/sandbox');

var db = mongoose.connection;

db.once('open',function(){
    console.log('Connection successful');
    // All db communication

    var Schema = mongoose.Schema;
    var AnimalSchema = new Schema({
        type:   {type: String, default: 'magikarp'}, // default values
        size:   String,
        color:  {type: String, default: 'orange'}, // default values
        mass:   {type: Number, default: 10}, // default values
        name:   {type: String, default: 'Shinji'} // default values
    });

        var Animal = mongoose.model('Animal',AnimalSchema); // Mongo will make Animal plural

    var elephant = new Animal({
        type: 'elephant',
        color: 'gray',
        mass: 6000,
                size:'big',
        name: 'Lawrence'
    });

    var whale = new Animal({
        type: 'whale',
        mass: 190500,
                size:'big',
        name: 'Fig'
    });

    var animal = new Animal({}); // defualt Magikarp value

        Animal.remove({},(err) => { // remove every Animal document, add query to remove specific ones
        if(err) console.error(err);
        elephant.save((err) => { // both the collection AND the (elephant) document will be saved now, not before
            if(err) console.error(err);
            animal.save((err) => { // Inside callback so that all animals are saved before db.close()
                if(err) console.error(err);
                whale.save((err) => { // Inside callback so that all animals are saved before db.close()
                    if(err) console.error(err);
                    Animal.find({size:'big'},(err,animals) => {
                        animals.forEach(( animal ) => {
                            console.log(animal.name + ' the ' + animal.color + ' ' +animal.type);
                        });
                        console.log('hello');
                        db.close(() => { // Inside callback since .close() is asynchronous
                            console.log('db connection closed');
                        });
                    });
                });
            });
        });
    });
});

/* Will log:
    Connection successful
    Lawrence the gray elephant
    Fig the orange whale
    hello
    db connection closed
*/