there are no spans for queries w/out exec() for mongoose 5.6.3

[evgeni-k]

Describe the bug
The library does not automatically creates span if there is no explicit exec() function call on query object.

Mongoose uses native Promise.

mongoose.Promise = global.Promise;

Following code snippet is instrumented perfectly and span is created

async function test() {
    const result = await Model.find().exec();
    console.log(result);
}

This code snippet cannot be automatically instrumented (span cannot be created)

async function test() {
    const result = await Model.find();
    console.log(result);
}

Mongoose automatically calls exec when then is called https://github.com/Automattic/mongoose/blob/5.6.3/lib/query.js#L4297-L4299

To Reproduce

Run code snippets below in your app.
If you run with explicit exec call then span is created otherwise it won't.

Expected behavior

Span should be created w/ and w/out explicit exec function call.

Environment (please complete the following information)

• OS: Mac OS 10.15.1
• Node.js version: 12.13.0
• APM Server version: 7.4.0
• Agent version: 3.1.0

How are you starting the agent? (please tick one of the boxes)

• Calling agent.start() directly (e.g. require('elastic-apm-node').start(...))
• Requiring elastic-apm-node/start from within the source code
• Starting node with -r elastic-apm-node/start

[Qard]

This is an unresolved issue with Promise Hooks in V8 and async_hooks in Node.js core. nodejs/node#22360

The only way to make this work is to fix it in V8.

[evgeni-k]

Thank you for your reply. Probably it makes sense to update docs to explicitly highlight that fact about custom thenable.

Feel free to close the ticket.

[sibelius]

does this also affects .aggregate?

[Systerr]

nodejs/node#22360 (comment) async_hooks was fixed

[Qard]

Yep, I fixed the issue in V8 a few months ago. It's in Node.js 14.x. Still waiting on the backport to land in 12.x.

[david-luna]

Just came across this issue and did some test to see if still apply. Mongoose is added to the support list in elastic-apm-agent@4 This new version does not support node <14 though.

I've used this example from the main branch to test also with the latest version of the 3.x branch.

req.waterfall:
    trace 9fe140
    `- transaction ed477c "t1" (34.813ms, outcome=unknown)
       `- span 8fac72 "example-trace-mongoose.people.insert" (1ms, mongodb)
       `- span bc7a36 "example-trace-mongoose.people.find" (1ms, mongodb)
       `- span b84aca "example-trace-mongoose.people.delete" (1ms, mongodb)
       `- span ec1f92 "admin.$cmd.endSessions" (0ms, mongodb, sync)

Mongoose eersions tested were: 7.6.3, 6.12.2, 5.13.21 & 5.6.3

So I'm inclined to close this one @evgeni-k if there is nothing else to look

[sibelius]

this is breaking for

mongoose 8.03
mongodb 6.2.0

[ccstuff]

this is breaking for这是打破

mongoose 8.03 猫鼬 8.03 mongodb 6.2.0

me too.

[email protected]
mongodb: 6.2.0

[sibelius]

It is working fine on latest version of packages