Fix Docker volume leak on SIGTERM, SIGHUP, and concurrent cleanup

src/index.ts

@@ -14,13 +14,23 @@ import packageJson from "../package.json";
 
 const jobs: Job[] = [];
 
-process.on("SIGINT", async (_: string, code: number) => {
-    await cleanupJobResources(jobs);
-    process.exit(code);
-});
+let cleanupAndExitPromise: Promise<void> | null = null;
+
+async function cleanupAndExit (code: number) {
+    // First caller's exit code wins — subsequent callers join the in-flight cleanup.
+    if (cleanupAndExitPromise) return cleanupAndExitPromise;
+    cleanupAndExitPromise = cleanupJobResources(jobs).finally(() => process.exit(code));
+    return cleanupAndExitPromise;
+}
+
+process.on("SIGINT", () => cleanupAndExit(130));
+process.on("SIGTERM", () => cleanupAndExit(143));
+process.on("SIGHUP", () => cleanupAndExit(129));
 
 // Graceful shutdown for nodemon
-process.on("SIGUSR2", async () => await cleanupJobResources(jobs));
+process.on("SIGUSR2", async () => {
+    if (!cleanupAndExitPromise) await cleanupJobResources(jobs);
+});
 
 (() => {
     const yparser = yargs(process.argv.slice(2));
@@ -42,8 +52,7 @@ process.on("SIGUSR2", async () => await cleanupJobResources(jobs));
                     } else {
                         process.stderr.write(chalk`{red ${e.stack ?? e}}\n`);
                     }
-                    await cleanupJobResources(jobs);
-                    process.exit(1);
+                    await cleanupAndExit(1);
                 }
             },
             builder: (y: any) => {

src/job.ts

@@ -772,11 +772,19 @@ If you know what you're doing and would like to suppress this warning, use one o
         }
     }
 
+    private _cleanupPromise: Promise<void> | null = null;
+
     async cleanupResources () {
         clearTimeout(this._longRunningSilentTimeout);
 
         if (!this.argv.cleanup) return;
 
+        if (this._cleanupPromise) return this._cleanupPromise;
+        this._cleanupPromise = this._doCleanupResources();
+        return this._cleanupPromise;
+    }
+
+    private async _doCleanupResources () {
         if (this._containersToClean.length > 0) {
             try {
                 await Utils.spawn([this.argv.containerExecutable, "rm", "-vf", ...this._containersToClean]);