Sentry.captureException doesn't close readable stream opened by createReadStream in getContextLinesFromFile

[mstrokin]

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

8.47.0

Framework Version

No response

Link to Sentry event

No response

Reproduction Example/SDK Setup

https://github.com/mstrokin/sentry-openfiles-bug

Steps to Reproduce

Running this in a Node Express server opens same files repeatedly without ever closing them, since 8.10.0 (8.9.0 works fine).

for (var i = 0; i < 1000; i++) {
Sentry.captureException('fake exception to test the files opening');
}

This is the cause of it: #12221

const stream = createReadStream(path);

this stream never gets closed (even though it supposed to use autoClose I think)

Expected Result

There are no open files in lsof output after sending the exceptions.

Actual Result

New files are opened every time captureException is called.

[mstrokin]

Repro:
https://github.com/mstrokin/sentry-openfiles-bug

[mstrokin]

Removed Express from the reproducible example, It's a Sentry bug after all.

[mstrokin]

The worst scenario happens if there's a loop doing captureException - it leads to same files being reopened & not closed.

I.e. If we call captureException using an Express route it doesn't open extra files with subsequent HTTP requests, it only reads files once it seems.

[AbhiPrasad]

Hey @mstrokin thanks for the repro and PR!

What version of node did you run the repro with? Want to see what test matrix to add to the PR.

Assigning myself this issue, will try to update the PR tomorrow and get it merged in!

[mstrokin]

Node v23.5.0 locally and Node v20 alpine on the server

Tested it again on all of these, works the same everywhere.
lts/fermium -> v14.21.3
lts/gallium -> v16.20.2
lts/hydrogen -> v18.20.5
lts/iron -> v20.18.1
lts/jod -> v22.12.0

[mstrokin]

Also, fun fact that I didn't debug - if you move the code into a single file (i.e. move App code into main.ts) - it stops happening, I guess it already has a file in the memory in that case.

[mstrokin]

I've debugged it a bit more and added new commit to repro repo, the bug is here - if we use lineReaded.removeAllListeners() it never closes the stream, not sure if it's a Node bug.

if (currentRangeIndex === ranges.length - 1) {
          // We need to close the file stream and remove listeners, else the reader will continue to run our listener;
          lineReaded.close();
          lineReaded.removeAllListeners();
          return;
}

[mstrokin]

nodejs/node#9002 Node says it's not a bug

[AbhiPrasad]

released with https://github.com/getsentry/sentry-javascript/releases/tag/8.49.0!