将对象添加到对象Node.js Express的子文档列表中

Question

我一直试图将DOM对象附加到Mongo数据库的Sub文档中的对象列表中。但是，到目前为止没有用。我从html表单中检索数据，在该表单中我将数据分组为对象。我首先尝试使用forEach循环，但是我不断收到一条消息，提示$ addToSet为空，尽管当我登录从DOM检索的对象时似乎也不为空。我采用了相同的方法，在前一条路由的放置请求中，然后更新数据库没有问题。这是我的第一个应用程序，我仍然是菜鸟，因此非常感谢您的帮助。

// my database Schema
// schema for images
var images = new Schema(
  {
    title: String,
    description: String,
    link: String
  }
);

// shema lower for the tes dictionary
var days = new Schema({
  day: Number,
  route: String,
  distance: Number,
  description: String,
  imageamount: Number,
  images: Array(images),

})

// schema upper for the test dictionary
var tourSchema  = new Schema({
  date: String,
  thumbnail: String,
  categories: Array,
  title: String,
  locations: Array,
  duration: Number,
  generalDescription: String,
  dayInfo: Array(days),
});

var Tour = mongoose.model("Tour", tourSchema);

// this is the code Im using to update the db

app.put("/tours/:id/dayinfo/images", (req, res) => {
  Tour.findById(req.params.id, (err, tour) => {
    if (err) {
      console.log("error");
    } else {
        for( var i = 0; i < tour.dayInfo.length; i++) {
          for (var j = 1; j <= tour.dayInfo[i].imageamount; j++){
            Tour.updateOne({_id: tour.dayInfo[i]._id}, {$addToSet: { images: req.body["images" + String(Number(i+1)) + String(j)] } },{upsert: true}, (err, updatedImages) => {
              if (err) {
                console.log(err);
              } else {
                  console.log(updatedImages);
              }
            })
          }
          console.log("updated imagess for images ");
        };
        res.redirect("/");
    }
  })
});

  <form class="some-form"  action="/tours/<%= tour._id %>/dayinfo/images?_method=PUT" method="POST">

             <% tour.dayInfo.forEach ( (day) => { %>
                  <header>
                    <h3>Images of <b>Day  <%= day.day %><b></h3>
                  </header>
                  <hr>

                   <% for (var i = 1; i <= day.imageamount; i++ ) { %>
                    <!-- tour info -->
                    <div class="row">
                      <div class="col-md-6">
                        <input type="text" name="images<%= day.day %><%= i %>[title]" value="" placeholder="Short title of image" class="form-control">
                      </div>
                      <div class="col-md-6">
                        <input type="text" name="images<%= day.day %><%= i %>[description]" value="" placeholder="Short description of image" class="form-control">
                      </div>
                    </div>
                    <br>
                    <input type="text" name="images<%= day.day %><%= i %>[link]" value="" placeholder="link of image" class="form-control">
                    <br>
                   <% } %>
          <% }); %>

          <input type="submit" name="" value="SAVE" class="btn btn-success btn-block">
        </form>

// this code seems to work, yet when applying the same approach for a deeper laying doc, it does not work i get a message saying that '\'addToSet'\' is empty.

/ update({_id: ObjectId("5bf404f0fd415e077e849694")}, {$addToSet: {dayInfo:  {day: 8} }}, {upsert: true} )
app.put("/tours/:id/dayinfo", (req, res) => {
    Tour.findById(req.params.id, (err, tour) => {
        if (err) {
          console.log(err)
        } else {
          for (var i = 1; i <= tour.duration; i++){
            Tour.update({_id: req.params.id}, {$addToSet: { dayInfo: req.body["dayInfo" + String(i)] } }, {upsert: true}, (err, updatedDayInfo) => {
              if (err) {
                console.log(err);
              } else {
                  console.log(req.body["dayInfo" + String(i)]);
              }
            })
          console.log("successfully updated day " + i );
          }
        }
    })
    res.redirect("/tours/" + req.params.id  + "/dayinfo/images" );
  });