How to use upsert | Exception while simulating the effect of invoking '' TypeError: Cannot read properties of undefined (reading '_id')

help
1

Hi, I’m having trouble with upsert . I could update questions finely with the below codes but I won’t be able to insert new data.

file in client side

const onSave = () =>{
       // there is  more codes but omitted
     questions.forEach(question => {
     Meteor.call('modifyQuestion', question);
 })
}

file in server side (collection file)

  modifyQuestion(question) {
    check(question, Object);

    const questionId = Measures.findOne({questionId: question._id});
    Measures.upsert(
      {_id: questionId._id},
      {
        $set: {
          title: question.text,
        },
      },
    );
  },

Got error saying…
Exception while simulating the effect of invoking 'modifyQuestion' TypeError: Cannot read properties of undefined (reading '_id')

I thought when {_id: questionId._id} got undefined, that’s the time upsert understand that there is no matching data found and insert as new data into the database.
Is this wrong?

2

it’s not the upsert error. The problem is the questionId is undefined.
you can change it from

{_id: questionId._id},

to

{_id: questionId?._id},

But it would lead you to other problem. The find condition will be empty object {}, which means it will match any record, then it will update the first one in your collection.
You should use 2 different cases for insert and update or modify the upsert condition like:

import { Random } from 'meteor/random'
...
{_id: questionId?._id || Random.id()},
3

Hi @miki11, Welcome to the forum :slight_smile:

it seems to me that this code is wrong… you don’t need to perform a findOne to do an upsert, you can simply just use it like this: {_id: question._id},

4

Thank you for your answer! @minhna and @hschmaiske

As you two suggested when I remove fiindOne and change operator, the error was gone!
I changed the code like below

  modifyQuestion(question) {
    check(question, Object);
    Measures.upsert(
      {questionId: questionId._id},  // changed _id to questionId
      {
        $set: {
          title: question.text,
        },
      },
    );
  },

Now my problem is I can update documents but not insert.

Do you have any ideas how to insert documents if they don’t exist?

Do I need to use not only $set but also $setOnInsert ?

I just saw a article that is using $setOnInsert when they have upsert

5

I’m sure that code doesn’t work. questionId is undefined.
When you’re not sure how to use upsert function, you can use insert and update instead.
For example:

if (document_exist) {
 // call update function
} else {
 // call insert function
}
6

Again Thank you for your answer!

Actually that’s exactly I’m trying to do now

modifyQuestion(question) {
  const checkExistingQuestion = Measures.findOne({questionId: question._id});

  if (checkExistingQuestion) {
    Measures.update(
      {questionId: question._id},
      {
        $set: {
          title: question.text,
        },
      },
    );
  } else {
    Measures.insert({
      $set: {
        title: question.text,
      },
    });
  }
},

And I’m seeing the error saying

while simulating the effect of invoking 'modifyQuestion' Error: When the validation object contains mongo operators, you must set the modifier option to true

I also tried removing findOne({}) and using if(question){ } else{ } but still got the same error…

Do you know what is meaning of this error? I’m googling but couldn’t figure out a answer

7

Check the format of insert parameters

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