DeleteComments ticket failing

MongoDB University M220J: MongoDB for Java Developers
#1

My unit tests are all passing. mflix is not throwing any exceptions while it’s executing, but it is giving me the following error:

Delete Comments: Deletion was performed but unsuccessful.

When I have it outputting the comment that’s being inserted versus the deletes it’s trying to do, the comment IDs do not match. Is anyone else running into the same problem?

#2

yes the same for me. Also that happens with “update comments” - tests pass, but no code from web site’s mflix status

#3

Hi @tjcasser,

Try putting commentId match in query filter. If that also does not work, please share the query.

Kanika

#4

Hi @Marina_37816,

Please share the error you are seeing from console when running the status page.

Kanika

#5

It’s still not working. I’ve actually tried it multiple ways and while the unit tests pass, the production continues to fail.
My current query that validates against the unit tests:

    Bson queryFilter = new Document("_id", new ObjectId(commentId)).append("email", email);
    DeleteResult dr = commentCollection.deleteOne(queryFilter);

What I am noticing (via some convenient System.out.println’s to see how it’s running) is that the mflix site seems to be trying to set the comment with a pre-set ID… and then goes looking for another one anyway.

Inserted comment from mflix:
Comment{id=5ce5d9cd4a50657dd15a2355, oid=5ce5d9cd4a50657dd15a2355, text=feefee, date=Wed May 22 19:22:53 EDT 2019, email=cxlrfh3pd@4goug.8mz, name=ke5o7f60q, movieId=573a13eff29313caabdd82f3, movieObjectId=573a13eff29313caabdd82f3}

Deletes are looking for:
Document{{_id=5a9427658b0beebeb697bc39, email=g9cwpr0bf@vyg4w.y2r}}
Document{{_id=5a9427658b0beebeb697bc39, email=cxlrfh3pd@4goug.8mz}}

5a9427658b0beebeb697bc39 is a different comment within the system.

#6

What do you return as the value of the method?

#7

return dr.getDeletedCount() == 1;

#8

That should work.

Just a wild guess but try to run the portal in incognito mode. Some people got issues with the cache.

#9

I tried that, actually. :frowning: No dice. I’m just soldiering on for the moment, but it annoys me.

#10

If not in the delete that the problem must lie in the insert. Are all the types the same? Some other people where adding _id not being an objectid and deleting with _id being an objectid.

#11

The inserts look like they’re going correctly too. It’s just annoying.

#12

no errors on console unfortunately. Just line turns red when in /status for udate/add comment and for delete comment; while tests for those two tickets run successfully. Please, can you do anything so that I would be able to be graded. I think that I did tickets correctly, when:
1.
mvn test -Dtest=DeleteCommentTest
works

mvn test -Dtest=UpdateCreateCommentTest
works.

If you do something incorrectly with JWT token, while i should lose grades?

#13

Are the comments sorted according to the requirements in getMovie*?

#14

I have exactly the same problem as guys here. Btw. something similar is happening for Create/Update comments Ticket Validation.

Here is my deleteComment implementation:

  public boolean deleteComment(String commentId, String email) {
    // TODO> Ticket Delete Comments - Implement the method that enables the deletion of a user
    // comment
    // TIP: make sure to match only users that own the given commentId
    final Bson filter = and(Arrays.asList(eq("_id", new ObjectId(commentId)), eq("email", email)));
    return commentCollection.deleteOne(filter).getDeletedCount() > 0;
    // TODO> Ticket Handling Errors - Implement a try catch block to
    // handle a potential write exception when given a wrong commentId.
  }

Of course all related unit tests are GREEN.

#15

To answer the question directly - yes, the types are the same.

For the record, the ‘suggested solution’ for create/update comments doesn’t pass when I substitute it for my code. I suspect there’s a deeper problem here with the mflix application’s test suite.

I’ve somewhat accepted that I’m just not going to get the delete working and have moved on.

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#16

Had the same problem and found the answer was due to missing something that wasn’t caught in a previous step.

Hint:- in the “Get Comments” ticket, the requirements included sorting the comments from newest to oldest. So if you haven’t got a $sort as part of your $lookup pipeline, try going back and adding that and then re-try the delete ticket.

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