How to save a Nested Object in MongoDB - mongodb

Question

const checkAuth = require("../../../util/checkAuth");
const { Post } = require("../../../models/post");
const { Like } = require("../../../models/like");
const upvoteComment = async (_, { username, postID, commentID }, context) => {
checkAuth(context);
/* TODO Securety concern one Person can upvote the same post via post request */
const like = new Like({
username: username,
createdAt: new Date(),
});
const post = await Post.findOne({ _id: postID });
const findComment = (post) => {
for (let i = 0; post.comments.length > i; i++) {
if (post.comments[i]._id == commentID) {
return i;
}`enter code here`
}
};
const index = findComment(post);
console.log(index, "index");
console.log(post.comments[0]);
post.comments[index].likes.push(like);
post.save();
return like;
};
module.exports = { upvoteComment };
I am trying to save a Like which I have modelled into a Comment on a Post. First I fetch the Post from my Mongo DB database, then I loop through the comments to find the comment with the id of the comment that was liked and I push the new like object into that comments likes array but when I save the like will not be saved... Does this have something to do with nesting?
So i changed the Code to this
const checkAuth = require("../../../util/checkAuth");
const { Post } = require("../../../models/post");
const { Like } = require("../../../models/like");
const upvoteComment = async (_, { username, postID, commentID }, context) => {
checkAuth(context);
/* TODO Securety concern one Person can upvote the same post via post request */
const like = new Like({
username: username,
createdAt: new Date(),
});
const post = await Post.findOne({ _id: postID });
console.log(post.comments);
const findComment = (post) => {
for (let i = 0; post.comments.length > i; i++) {
if (post.comments[i]._id == commentID) {
return i;
}
}
return -1;
};
const index = findComment(post);
/* console.log(index, "index");
console.log(post.comments[index]);
*/
if (index !== -1) {
post.comments[index].likes.push(username);
post.comments[index].likes.push(like);
post.title="this title will be saved"
const res = await post.save();
console.log("likes on the server: ", res.comments[index].likes);
}
const savedPost = await Post.findOne({ _id: postID });
console.log("likes on Database: ", savedPost.comments[index].likes);
return like;
};
module.exports = { upvoteComment };
and the console will return this:
likes on the server: [
'username',
{
_id: 6081838453f4aa1ff4db6b5e,
username: 'username',
createdAt: 2021-04-22T14:09:08.817Z
}
]
likes on Database: []
This does indeed change the title of the post so I have concluded that mongoDB sees the post.comment[i].likes field as uneditable even though i have declared it as an Array... The type of item doesnt matter for this either as i have tested it in this example.

Answer 1

Try this once hope it works for you.
const upvoteComment = async (_, { username, postID, commentID }, context) => {
checkAuth(context);
/* TODO Securety concern one Person can upvote the same post via post request */
const like = new Like({
username: username,
createdAt: new Date(),
});
const post = await Post.findOne({ _id: postID });
const findComment = (post) => {
for (let i = 0; post.comments.length > i; i++) {
if (post.comments[i]._id == commentID) {
return i;
}
}
return -1;
};
const index = findComment(post);
console.log(index, "index");
console.log(post.comments[0]);
if(index !== -1)
post.comments[index].likes.push(like);
await post.save();
return like;
};

Answer 2

Try using
post.comments[i].likes.push({
username: "johndoe",
createdAt: new Date(),
});
instead of using new Like({...})
By the way, you should use findIndex for conciseness and clarity:
...
const i = post.comments.findIndex(comment => comment._id === commentID);
post.comments[i].likes.push(like);
await post.save();
...

Answer 3

So the Problem lied within my Schema definiotion and was a simple Typo I apologize to everyone that tried to wrap their head around this...