How to store `_id` in a different document in different collection right after a document is inserted

help
1

What I need to do is… store _id in the different document in different collection right after a document is inserted.

For example, I have a button to create or edit todos. Each todo has _id, title and description. So after hitting the save button, users can create a new todo or update an existing todo.

And I’m focusing on creating a new todo here.

client side

const Todos = ({ listId }) => {
  const [title, setTitle] = useState('')
  const [description, setDescription] = useState('')

  const listId = '12312313'

  const handleUpdate = ({title, description}) => {
    Meteor.call("updateTodo", _id, title, description, listId);
  };

  return (
    <>
    .
    .
    .
      <button onClick={handleUpdate}>Update or create todo</button>
    </>
  );
};

server side

Meteor.methods({
  updateTodo(_id = "", title, description, listId) {
    check(_id, Match.Maybe(String));
    check(title, String);
    check(description, String);
    check(listId, String);

    Todos.update(
      { _id },
      {
        $set: {
          title: title,
          description: description,
        }
      },
      { upsert: true, multi: false } 
    );
  }
});

I like to store _id that’s not existing in Todos collection yet in one of the documents in Lists collection when the save button is clicked.

So the flow will be
1, Users click the save button to create a new todo
2, updateTodo gets called
3, Title, description are stored in a new document (mongodb automatically generates _id)
4, _id needs to be stored in todoIds property that’s in Lists collection (I have access to listsId so I can get an document from Lists collection that I need to store this _id)

I do not know how to access _id in Todos collection and also don’t know how to store it in the document in Lists collection.

Attempts

I simply added this code below after Todos.update()

Lists.direct.update(listId, {$set: {todoIds: [_id]}});

I checked if the document in Lists collection is updated but todoIds property is set to [null]. what I want to store is _id from the document in Todos collection.

additional question

Right now if Lists.direct.update(listId, {$set: {todoIds: [_id]}}); works, the todoIds property will be overwritten by _id.

But what I want to do here is add _id to the end of the todoIds array so the document would look like this.

{
    _id:'1231231',
    todoIds : [
       'asdasssdasd',
       'dfgthfghfhf',
       'slirfjlsffs'   // that's _id from the document in Todos collection
    ]
}

Thanks in advance.

2

you modify your updateTodo so you will have the _id valuet:

updateTodo(_id = "", title, description, listId) {
    check(_id, Match.Maybe(String));
    check(title, String);
    check(description, String);
    check(listId, String);

  let theId;
  if (!_id) {
    // do insert here
    theId = Todos.insert()
  } else {
    // do update here
    
    theId = _id;
  }

  // now you have theId variable
``
1 Like
3

It worked Thank you!

1 Like