Recently, I encountered an error while trying to add comments to my posts by using nested populate for mongoose. Initially, everything was working fine when I only pre-populated user data. However, as soon as I implemented nested populate, I started receiving an error stating "posts is not iterable". To provide more clarity on this issue, I have shared a snippet of my code below.
Error
TypeError: /home/vivek/Vivek/CN WEBD/codel/views/home.ejs:16
14| <div id="posts-list-container">
15| <ul>
>> 16| <% for (post of posts){ %>
17|
18|
19| <li>
posts is not iterable
at eval (eval at compile (/home/vivek/Vivek/CN WEBD/codel/node_modules/ejs/lib/ejs.js:662:12), <anonymous>:21:21)
at home (/home/vivek/Vivek/CN WEBD/codel/node_modules/ejs/lib/ejs.js:692:17)
...
// Remaining error stack trace omitted for brevity
Home_controller.js:
const Post = require('../models/post');
module.exports.home = function(req, res){
Post.find({})
.populate('user').
populate({
path: 'comments',
populate: {
path: 'user'
}
})
.exec(function(err, posts){
return res.render('home', {
title: "Home",
posts: posts
});
})
};
Home.ejs: where i am trying to fetch the data
<div id="posts-list-container">
<ul>
<% for (post of posts ){ %>
<li>
<p><%= post.user.name %>
<%= post.content %>
</p>
<div class="post-comments">
<% if (locals.user){ %>
<form action="/comments/create" method="POST">
<input type="text" name="content" placeholder="type here to comment">
<input type="hidden" name="post" value="<%= post._id%>">
<input type="submit" value="Add comment">
</form>
<%}%>
<div class="post-comment-list">
<ul id="post-comments-<%= post._id %>">
<% for (comment of posts.comments){ %>
<p>
<%= comment.content %>
<br>
<small>
<%= comment.user.name %>
</small>
</p>
<%} %>
</ul>
</div>
</div>
</li>
<% }%>
</ul>
</div>
CommentsSchema model
const mongoose = require('mongoose');
const commentScehma = new mongoose.Schema({
content:{
type: String,
required: true
},
//comment belogns to user
user: {
type: mongoose.Schema.Types.ObjectId,
ref: 'User'
},
post: {
type: mongoose.Schema.Types.ObjectId,
ref: 'Post'
}
},{
timestamps: true
})
const Comment = mongoose.model('Comment', commentScehma)
module.exports = Comment;
Post Schema Model
const mongoose = require('mongoose');
const postSchema = new mongoose.Schema({
content: {
type: String,
required: true
},
user: {
type: mongoose.Schema.Types.ObjectId,
ref: 'User'
},
// inclue the array of id's of all comments in this post schema itself
comments: [
{
type: mongoose.Schema.Types.ObjectId,
ref: 'comment'
}
]
},{
timestamps: true
});
const Post = mongoose.model('Post', postSchema);
module.exports = Post;