Hoot Back-End Delete Comment

Learning objective: By the end of this lesson, students will be able build a route that deletes embedded subdocuments inside a single hoot.

Overview

In this section, we will create a delete route to find and delete a single comment within a hoot.

We will be following these specs when building the route:

CRUD Action: DELETE
Method: DELETE
Path: /hoots/:hootId/comments/:commentId
Response: JSON
Success Status Code: 200 Ok
Success Response Body: A JSON status message.
Error Status Code: 500 Internal Server Error
Error Response Body: A JSON object with an error key and a message describing the error

Define the route

Our route will listen for DELETE requests on /hoots/:hootId/comments/:commentId:

DELETE /hoots/:hootId/comments/:commentId

Add the following to controllers/hoots.js:

// controllers/hoots.js

router.delete("/:hootId/comments/:commentId", verifyToken, async (req, res) => {
  // add route
});

🧠 This route might be seem intimidating at first. It requires both a hootId a commentId, so that we can locate both the parent, and then the child document within it.

❗ A user needs to be logged in to update a comment, so be sure to include the verifyToken middleware.

Code the controller function

Let’s breakdown what we’ll accomplish inside our controller function.

First we call upon the Hoot model’s findById() method. The retrieved hoot is the parent document that holds an array of comments. We’ll need to remove a specific comment from this array.

To do so, we’ll make use of the MongooseArray.prototype.remove() method. This method is called on the array property of a document, and removes an embedded subdocument based on the provided query object ({ _id: req.params.commentId }).

After removing the subdocument, we save the parent hoot document, and issue a JSON response with a message of Ok.

Add the following to controllers/hoots.js:

// controllers/hoots.js

router.delete("/:hootId/comments/:commentId", verifyToken, async (req, res) => {
  try {
    const hoot = await Hoot.findById(req.params.hootId);
    const comment = hoot.comments.id(req.params.commentId);

    // ensures the current user is the author of the comment
    if (comment.author.toString() !== req.user._id) {
      return res
        .status(403)
        .json({ message: "You are not authorized to edit this comment" });
    }

    hoot.comments.remove({ _id: req.params.commentId });
    await hoot.save();
    res.status(200).json({ message: "Comment deleted successfully" });
  } catch (err) {
    res.status(500).json({ err: err.message });
  }
});

Test the route in Postman

Now that we have finished the route let’s test it with Postman. We’ll do this by sending a DELETE request to /hoots/:hootId/comments/:commentId.

Create a new request in Postman. Let’s name this request Delete Comment and set its request type to DELETE. Your Postman URL should look something like this.

http://localhost:/hoots/63390dddff7c27bc4b86a1aa/comments/633915e08845c5a891cd4bf2

Your Postman request should look something like this:

Delete request

The response should be an object containing a message: "Comment deleted successfully" property:

Delete response