github/oneuptime
1
1
Fork 0
mirror of https://github.com/OneUptime/oneuptime.git synced 2026-04-06 00:32:12 +02:00
Code Issues 193 Packages Projects Releases Wiki Activity

feat: Implement child process termination logic to prevent leaks in SyntheticMonitor

Browse Source
This commit is contained in:
Nawaz Dhandala
2026-02-26 18:25:46 +00:00
parent 43d4854917
commit ad9e937b9e
1 changed files with 44 additions and 1 deletions
Download Patch File Download Diff File Expand all files Collapse all files

45
Probe/Utils/Monitors/MonitorTypes/SyntheticMonitor.ts
View File

@@ -253,12 +253,51 @@ export default class SyntheticMonitor {
});
}
/**
* Ensure the child process is always killed to prevent leaked processes.
* The worker calls process.exit() on itself, but if that hangs (e.g.
* browser cleanup holding a ref) the child would linger until the OS
* reclaims it. We send SIGTERM first to allow graceful shutdown, then
* schedule a SIGKILL as a guaranteed cleanup.
*/
const ensureChildKilled: () => void = (): void => {
try {
if (child.exitCode === null && child.signalCode === null) {
// Child is still running — ask it to exit gracefully
child.kill("SIGTERM");
// If it doesn't exit within 5s, force-kill
const forceKillTimer: ReturnType<typeof setTimeout> =
global.setTimeout(() => {
try {
if (child.exitCode === null && child.signalCode === null) {
child.kill("SIGKILL");
}
} catch {
// ignore — process may have already exited
}
}, 5000);
// Don't let this timer keep the parent process alive
if (forceKillTimer.unref) {
forceKillTimer.unref();
}
}
} catch {
// ignore — process may have already exited
}
};
// Explicit kill timer as final safety net (well beyond the worker's own safety timer)
const killTimer: ReturnType<typeof setTimeout> = global.setTimeout(
() => {
if (!resolved) {
resolved = true;
child.kill("SIGKILL");
try {
child.kill("SIGKILL");
} catch {
// ignore — process may have already exited
}
reject(
new Error("Synthetic monitor worker killed after timeout"),
);
@@ -271,6 +310,8 @@ export default class SyntheticMonitor {
if (!resolved) {
resolved = true;
global.clearTimeout(killTimer);
// Kill the child in case it hangs during its own cleanup
ensureChildKilled();
resolve(result);
}
});
@@ -279,6 +320,8 @@ export default class SyntheticMonitor {
if (!resolved) {
resolved = true;
global.clearTimeout(killTimer);
// Kill the child — it errored but may still be running
ensureChildKilled();
reject(err);
}
});