Bug: Calling method after awaiting something else causes `Called saveOriginals twice without retrieveOriginals` error

[wildhart]

This is a weird bug which occurs when calling a method to insert or upsert a document into a collection after a UI button click but first doing something async.

Steps to reproduce

Packages:

• jam:method@1.7.1
• jam:offline@0.2.2 - however keepAll is false, and for the purposes of this repro I've not called keep() on this collection, and the bug occurs when online, so I'm pretty sure this bug is not in jam:offline.

Here's my method - just a simple upsertAsync (but I've also tried insertAsync, and the sync versions with the same error result).

import { createMethod } from 'meteor/jam:method';

export const siteInspectionMethods = {
    upsertJam: createMethod({
        name: 'inspections.upsertJam',
        validate(inspection: SiteInspection) {
            /************************** VALIDATE PERMISSIONS ***********************************/
            check(this.userId, Match.isStaff);
            /************************** VALIDATE INPUTS ****************************************/
            check(inspection._id, Match.stringNotBlank);
            /***********************************************************************************/
        },
        async run(inspection: SiteInspection) {
            console.log('Method: inspections.upsertJam', inspection._id);
            await inspectionsCollection.upsertAsync(inspection._id, inspection);
            return inspection._id;
        },
    }),

And then a simple click handler in the UI:

async onButtonClick() {
    // simulate doing something async:
    await new Promise(resolve => setTimeout(resolve, 100));
    await siteInspectionMethods.upsertJam({_id: Random.id()});
},

Clicking the button causes this error (note that none of these trace lines are in jam:offline or jam:method):

If you remove the await new Promise(resolve => setTimeout(resolve, 100)); line, then it works without an error, and the document is upserted correctly.

If I remove jam:method by defining a simple method instead:

Meteor.methods({
    async upsertInspection(inspection: SiteInspection) {
        console.log('Method: upsertInspection', inspection._id);
        await inspectionsCollection.upsertAsync(inspection._id, inspection);
    },
});

Then call this method instead, after the delay:

async onButtonClick() {
    await new Promise(resolve => setTimeout(resolve, 100));
    //await siteInspectionMethods.upsertJam({_id: Random.id()});
    Meteor.call('upsertInspection', {_id: Random.id()});
},

Then it works OK without any error messages.

This also works:

async onButtonClick() {
    setTimeout(() => {
        siteInspectionMethods.upsertJam({_id: Random.id()});
    }, 100);
},

But this FAILS with the same error:

onButtonClick() {
    new Promise(resolve => setTimeout(resolve, 100)).then(() => {
        siteInspectionMethods.upsertJam({_id: Random.id()});
    });
},

Any ideas? Can you repro this?

[jamauro]

I will take a closer look soon but out of curiosity, is this with Meteor 2.16? Can you repro with 2.14 or 3.0.2?

[wildhart]

Yes, this is 2.16. I will try 2.14 later and let you know how I get on...

[jamauro]

I wasn't able to reproduce with async / await syntax.

async onButtonClick() {
    // simulate doing something async:
    await new Promise(resolve => setTimeout(resolve, 100));
    await siteInspectionMethods.upsertJam({_id: Random.id()});
}

I was able to reproduce with

onButtonClick() {
    new Promise(resolve => setTimeout(resolve, 100)).then(() => {
        siteInspectionMethods.upsertJam({_id: Random.id()});
    });
}

And more importantly I was able to reproduce without using jam:method:

onButtonClick() {
    new Promise(resolve => setTimeout(resolve, 100)).then(() => {
        Meteor.callAsync(methodName, ...args)
    });
}

I think this issue lies with Meteor 2.x itself and not this package. I remember a discussion a while back about some limitations with regard to *Async collection methods. I think some (maybe all) of those limitations were captured here: https://github.com/zodern/fix-async-stubs# which led to zodern's solution being incorporated into 3.x

[wildhart]

FYI I was able to reproduce on Meteor 2.14

Installing meteor add zodern:fix-async-stubs seems to resolve the issue, thanks for that. Feel free to close this issue.