/Javascript/Express/How to Delete Comment from Post on Node, express and Mongoose and Ajax

How to Delete Comment from Post on Node, express and Mongoose and Ajax

// How to Delete Comment from Post on Node, express and Mongoose and Ajax

You need to know both the postId and the commentId to be able to delete the comment from posts collection. Also it would be good to delete the comment inside the comments collection.

So change your delete route to include postId and commentId as req.params. You can delete a comment from posts using the findByIdAndUpdate method and $pull operator.

router.delete("/comments/:postId/:commentId", async function (req, res) {
  try {
    const post = await Post.findByIdAndUpdate(
      req.params.postId,
      {
        $pull: { comments: req.params.commentId },
      },
      { new: true }
    );

    if (!post) {
      return res.status(400).send("Post not found");
    }

    await Comment.findByIdAndDelete(req.params.commentId);

    res.send("Success");
  } catch (err) {
    console.log(err);
    res.status(500).send("Something went wrong");
  }
});
TEST

Let's say we have this post document with 3 comments.

Posts:

{
    "_id" : ObjectId("5e8b10c49ae619486094ed10"),
    "comments" : [
        ObjectId("5e8b104f9ae619486094ed0d"),
        ObjectId("5e8b10599ae619486094ed0e"),
        ObjectId("5e8b105e9ae619486094ed0f")
    ],
    "title" : "Title",
    "description" : "Description...",
    "from" : "From",
    "postImage" : "Post Image",
    "createdAt" : ISODate("2020-04-06T14:21:40.884+03:00")
}
Comments:

{
    "_id" : ObjectId("5e8b105e9ae619486094ed0f"),
    "message" : "Comment 3"
},

{
    "_id" : ObjectId("5e8b10599ae619486094ed0e"),
    "message" : "Comment 2"
},
{
    "_id" : ObjectId("5e8b104f9ae619486094ed0d"),
    "message" : "Comment 1"
}
If we want to delete the comment with _id:5e8b10599ae619486094ed0e, we need to send a DELETE request to our route using url like this:

http://localhost:3000/posts/comments/5e8b10c49ae619486094ed10/5e8b10599ae619486094ed0e
5e8b10c49ae619486094ed10 is the postId, 5e8b10599ae619486094ed0e is the commentId.

Result will be like this:

Posts:

{
    "_id" : ObjectId("5e8b10c49ae619486094ed10"),
    "comments" : [
        ObjectId("5e8b104f9ae619486094ed0d"),
        ObjectId("5e8b105e9ae619486094ed0f")
    ],
    "title" : "Title",
    "description" : "Description...",
    "from" : "From",
    "postImage" : "Post Image",
    "createdAt" : ISODate("2020-04-06T14:21:40.884+03:00")
}
Comments:

{
    "_id" : ObjectId("5e8b105e9ae619486094ed0f"),
    "message" : "Comment 3"
},
{
    "_id" : ObjectId("5e8b104f9ae619486094ed0d"),
    "message" : "Comment 1"
}
Share
Follow
answered Apr 6 '20 at 11:37

SuleymanSah
12.8k55 gold badges1717 silver badges4242 bronze badges
1
@SuleymanSahThank you so much for taking your time to explain to me how it works, i really appreciate it. I did exactly what you said with the code you gave me above, and changed my link to include post id like this ` <a class="delete-comment" href="#" data-id="<%=post.id%>/<%=item._id%>">Delete</a> ` and everything is – Chukwuma Kingsley Apr 6 '20 at 11:58

Similar codes

0 vote208 views1 answer
Error sending empty object express
Javascript Express
1 vote234 views1 answer
Express static auth
Javascript Express
0 vote196 views1 answer
Insert a data into mongo using express
Javascript Express
-2 votes221 views3 answers
React and express
Javascript Express
8 votes209 views1 answer
Express router file
Javascript Express
7 votes186 views3 answers
Express request path
Javascript Express
0 vote184 views1 answer
Apex express 18 forgot password
Javascript Express
0 vote190 views1 answer
Err handling express
Javascript Express
11 votes258 views4 answers
Node express setup
Javascript Express
3 votes230 views1 answer
Express get cookie
Javascript Express