Mongoose Populate not working while querying data - node.js

Question

I have 2 models, category and story.
Story contains reference id of the category.
In controller story, I have a function mystories which should fetch all the story records of particular user along with category information.
I am getting data from story collection but not from category collection.
The result which I receive is something like this:
category_id: "5d10978c8e0f5d5380fdb3e6"
created_at: "2019-06-25T10:02:47.637Z"
created_by: "5d1066fba920ef2ccfe68594"
image: "uploads/1561456967615_164.jpg"
published: "no"
status: "pending"
text: "<p><strong>Fashion</strong> is a popular aesthetic expression in a certain time and context, especially in clothing, footwear, lifestyle, accessories, makeup, hairstyle and body </p>"
title: "New fashion"
__v: 0
_id: "5d11f14757f8616041616217"
It should however return category collection information instead of
category id.
Category model:
const mongoose = require('mongoose');
const categorySchema = mongoose.Schema({
_id: mongoose.Schema.Types.ObjectId,
name: {
type: String,
required: true,
unique: true
},
status: {
type: String,
required: true,
enum: ['active','inactive','deleted']
},
created_at: { type: Date, default: Date.now },
created_by: { type: mongoose.Schema.Types.ObjectId, ref: 'User', required: true},
});
module.exports = mongoose.model('Category', categorySchema);
Story model:
const mongoose = require('mongoose');
const storySchema = mongoose.Schema({
_id: mongoose.Schema.Types.ObjectId,
title: {
type: String,
required: true
},
text: {
type: String,
required: true
},
category_id: {
type: mongoose.Schema.Types.ObjectId,
ref: 'Category',
required: true
},
image: {
type: String,
required: true
},
status: {
type: String,
required: true,
enum: ['pending','approved','deleted']
},
published: {
type: String,
required: true,
enum: ['yes','no']
},
created_at: { type: Date, default: Date.now },
created_by: { type: mongoose.Schema.Types.ObjectId, ref: 'User', required: true},
});
module.exports = mongoose.model('Story', storySchema);
Controller code:
const mongoose = require('mongoose');
const Story = require('../models/story');
const Category = require('../models/category');
exports.mystories = async (req, res, next) => {
const user_id = req.userData.id;
const all_stories = await Story
.find({ created_by: user_id})
.populate('name','category')
.sort({ created_at: -1 })
.exec();
if(all_stories.length > 0) {
return res.status(200).json({
response: all_stories
});
}else {
return res.status(200).json({
response: []
});
}
};
exports.add_story = (req, res, next) => {
console.log(req.file);
const story = new Story({
_id: new mongoose.Types.ObjectId(),
title: req.body.story_title,
text: req.body.story_text,
category_id: req.body.story_category,
image: req.file.path,
status: 'pending',
published: 'no',
created_by: req.userData.id
});
story
.save()
.then(result => {
console.log(result);
res.status(200).json({
response: 'added_story'
});
})
.catch(err => {
console.log(err);
res.status(500).json({
error: err
})
});
};

Answer 1

populate takes the field name as it is given in story schema.
it should be :
.populate({path: 'category_id', select: 'name'})