[SOLVED] Smart contract event handling- issue with beforeSave trigger

Moralis General
#1

Hi,
I’m trying to create a very basic cloud function trigger for my smart contract event, but it’s not working.
Just for testing, I trimmed everything, and kept the basic functionality, and it still does not work, not sure where exactly is the issue here:

Cloud function code:

Moralis.Cloud.beforeSave("EQuestionStatusNEW", (request) => {
    const Question = Moralis.Object.extend("EQuestionNEW");
    const query = new Moralis.Query(Question);
    query.equalTo("questionId", 2);
    const question = await query.first();
    question.set("questionStatusId", 1);    // this is not updated in collection
    question.save();    
});

EQuestionStatusNEW & EQuestionNEW are the collection names.

Can you please help resolve this.

1 Like
#2

Hey @vikasg

Looks like you are trying to find a record in the database before it was made.

question is probably undefined

You can use afterSave trigger instead. Or you can edit your code a bit for using it with beforeSave":

You need to get info from request object, because the record you are trying to get doesn’t exist in the db yet.

Here how should your code look like:

Moralis.Cloud.beforeSave("EQuestionStatusNEW", async (request) => {
    const questionId = request.object.get("questionId");
    question.set("questionStatusId", 1);    // this is not updated in collection
    await question.save();    
});

Hope this helps :man_mechanic:

1 Like
#3

Thanks @Yomoo for your reply.

Makes sense to use afterSave trigger here, will do that.

Also, EQuestionNEW is a different collection altogether, and it has entry with questionId = 2. The requirement here is to update a different collection (EQuestionNEW) once I receive event from smart contract.

    const Question = Moralis.Object.extend("EQuestionNEW");
    const query = new Moralis.Query(Question);
    query.equalTo("questionId", 2);
    const question = await query.first();

I saw this await was missing from my code earlier, but even after putting this, its not updating the EQuestionNEW collection.
await question.save();

So final expected code should look like this:

Moralis.Cloud.afterSave("EQuestionStatusNEW", (request) => {
    const questionId =  request.object.get("questionId");
    const questionStatusId =  request.object.get("questionStatusId");
    
    const Question = Moralis.Object.extend("EQuestionNEW");
    const query = new Moralis.Query(Question);
    query.equalTo("questionId", questionId);
    const question = await query.first();
    
    question.set("questionStatusId", questionStatusId);
    await question.save();    
});
#4

you could check if a question object was found there
it will not work if no object is found
you can also try to use master key in case that it is needed

#5

Object is there. I also checked Moralis admin log, strange error there:

2022-01-08T11:24:05.517Z - TypeError: Cannot read properties of undefined (reading 'set')
    at eval (eval at customUserPlugin (/moralis-server/cloud/main.js:140:21), <anonymous>:1:213)
    at processTicksAndRejections (node:internal/process/task_queues:96:5)
2022-01-08T11:24:05.515Z - afterSave failed for EQuestionStatusNEW for user undefined:
  Input: {"block_timestamp":{"__type":"Date","iso":"2022-01-08T11:24:04.000Z"},"transaction_hash":"0x3589f438656633f521352f786461f22654995a5837d660da6395ff8e3c7bfca5","log_index":0,"questionId":"4","questionStatusId":"1","address":"0x2a0ea93f4979ddaf532ac65ec5345e4cc4828fbf","block_hash":"0x24e2dcd692591f48408a259d96223c8cb5eefc39798320c592fe3cc581fdf96b","block_number":15682380,"transaction_index":0,"createdAt":"2022-01-08T11:24:05.490Z","updatedAt":"2022-01-08T11:24:05.490Z","objectId":"EaYkbechbyrimaFOmglJxdeC"}
  Error: {"message":"Cannot read properties of undefined (reading 'set')","code":141}

Could not understand the error:

  Error: {"message":"Cannot read properties of undefined (reading 'set')","code":141}

This column questionStatusId do exists in EQuestionNEW collection.
Any quick help would be appreciated, seems I’m stuck for a while now.

#6

you can check if that query returned an object, it looks like it returns undefined from that error

#7

Its resolved now. The last issue was related to collection column datatype.
Thanks everyone for your help. Really appreciate it!

1 Like