在猫鼬中集合引用是如何工作的？

Question

First time i am trying to use refrence in mongoose , so i am trying to understand if i want to save template with user id , Do we need to get createdBy value from client or how it will be inserted into templateSchema . basically i want to save user id _id when user save template.I was able to save template but i did not get any error and createdBy property did not saved to template collection. Any layman explanation to understand refrencing in mongoose and how i can make it work with below code.

user.js

var UserSchema = new mongoose.Schema({
  _id: { type: String, required: true, index: {unique: true}},
  firstName: String,
  lastName: String,
  type: String,
  groups:[{type: String, ref: 'Group', required: false}]
},
  {
    toObject: {
      virtuals: true
    },
    toJSON: {
      virtuals: true
    }
  });

template.js

var User = require('../user/user.model.js');

var TemplateSchema = new mongoose.Schema({
  _id: { type: String, required: true},
  name: String,
  id: String,
  appliesTo: [],
  properties: [],
  createdBy: { type: mongoose.Schema.Types.ObjectId, ref: 'User'}
 });

templateCtrl.js

var eTemplate = require('./template.model');

var templatesJavaClass = {
          "_id": 12586,
          "name": "Java Class",
          "id": "javaClass",
          "appliesTo": [
              "bpmn:UserTask"
          ],
          "properties": [{
              "label": "Java Package Name",
              "type": "String",
              "editable": true,
              "binding": {
                  "type": "property",
                  "name": "camunda:class"
              }
          }],
        "createdBy": "user1"
      }

 var template = new eTemplate(templatesJavaClass);

 template.save(function(error){
  console.log("successfully saved template");
  if (error){
    console.log(error);
  }
 });

Answer 1

You need to put user _id in createdBy field of template document while creating/saving it.

Also, make sure it is of Type ObjectId and not string . Otherwise you might get Cast Error .

Try this:

var templatesJavaClass = {
    "_id": 12586,
    "name": "Java Class",
    "id": "javaClass",
    "appliesTo": [
        "bpmn:UserTask"
    ],
    "properties": [{
        "label": "Java Package Name",
        "type": "String",
        "editable": true,
        "binding": {
            "type": "property",
            "name": "camunda:class"
        }
    }],
  //save users _id in createdBy field
  "createdBy": user1._id;//assuming user1 is the users document
}

var template = new eTemplate(templatesJavaClass);

template.save(function(error){
    console.log("successfully saved template");
    if (error){
      console.log(error);
    }
});