Printed errors should show cause

[OliverJAsh]

Is there an existing issue for this?

• I have checked for existing issues https://github.com/getsentry/sentry-javascript/issues
• I have reviewed the documentation https://docs.sentry.io/
• I am using the latest SDK release https://github.com/getsentry/sentry-javascript/releases

How do you use Sentry?

Sentry Saas (sentry.io)

Which SDK are you using?

@sentry/node

SDK Version

7.64.0

Framework Version

No response

Link to Sentry event

No response

SDK Setup

No response

Steps to Reproduce

const Sentry = require('@sentry/node');
Sentry.init({ dsn: 'https://[email protected]/123' });

throw new Error('foo', { cause: 'bar' });

Expected Result

The printed error should include the cause.

Actual Result

The printed error does not include the cause:

$ node test.js
Error: foo
    at Object.<anonymous> (/Users/oliver/Code/unsplash/unsplash-web/test.js:4:7)
    at Module._compile (node:internal/modules/cjs/loader:1254:14)
    at Module._extensions..js (node:internal/modules/cjs/loader:1308:10)
    at Module.load (node:internal/modules/cjs/loader:1117:32)
    at Module._load (node:internal/modules/cjs/loader:958:12)
    at Function.executeUserEntryPoint [as runMain] (node:internal/modules/run_main:81:12)
    at node:internal/main/run_main_module:23:47

If we remove Sentry.init, the cause is shown:

$ node test.js
/Users/oliver/Code/unsplash/unsplash-web/test.js:4
throw new Error('foo', { cause: 'bar' });
^

Error: foo
    at Object.<anonymous> (/Users/oliver/Code/unsplash/unsplash-web/test.js:4:7)
    at Module._compile (node:internal/modules/cjs/loader:1254:14)
    at Module._extensions..js (node:internal/modules/cjs/loader:1308:10)
    at Module.load (node:internal/modules/cjs/loader:1117:32)
    at Module._load (node:internal/modules/cjs/loader:958:12)
    at Function.executeUserEntryPoint [as runMain] (node:internal/modules/run_main:81:12)
    at node:internal/main/run_main_module:23:47 {
  [cause]: 'bar'
}

It seems that Sentry is changing the way that exceptions are printed. I believe this custom logic needs to be updated to include the cause. Furthermore, I am wondering if it's possible to disable this and use Node's default behaviour?

[Lms24]

Hi @OliverJAsh thanks for writing in!

I took a look at this and can confirm that we're not showing the cause (or fwiw any other properties of an error), in case the error has a stack trace.

First of all, the Node SDK registers a handler for UncaughtException which will override the default behaviour. By default, the entire error object seems to be logged, along with the code line and the Node version (basically, what you showed in your last snippet).

We try to emulate this default behaviour by explicitly logging the error to the console but for some reason, we only log the stack trace if the error has one (as in your example), meaning, we omit other error properties, such as cause:

sentry-javascript/packages/node/src/integrations/utils/errorhandling.ts

Line 13 in 891a44e

console.error(error && error.stack ? error.stack : error);

I tried tracking down why we're doing this but couldn't find an explanation other than that we seemed to have added it when we moved from raven-node (very old SDK version) to @sentry/node.

I'll open a PR to just always log the entire error instead here. This won't 1:1 replicate the entire default logging behaviour but at least it'll show you cause (or other properties).

[Lms24]

FYI, the cause field is only shown on Node 16 and newer. Previous Node versions only printed the stack trace of the error when calling console.error(err) but also when directly throwing the error and using Node's default behaviour.