title: Push item to array, only first property is included. Mongoose
body: <p>Schema:</p>
  
  <pre><code>let projectSchema = new Schema({
    filters: [
      {
        name: { type: String, required: true},
        items: {
          q: { type: Number, required: true}
        }
      }
    ],
  });
  </code></pre>
  
  <p>Update function:</p>
  
  <pre><code>const project = await mongoose.model('project').findById(id).exec();
      console.log(filter); // { name: 'abc', items: [ { q: 3}]
      project.filters.push(filter);
      console.log(project.filters); // { _id: "123", name: 'abc' } // items array is missing
      await project.save();
  </code></pre>
  
  <p>When I fetch a document via mongoose, then add an item to an array of that doc, only the first property is included.</p>
  
  <p>Why is that?</p>
  
  <p>I prefer not to use $push since the benefits of mongoose (validation etc) is not respected when $push is used.</p>