feat: support using process.on to listen SIGTERM (#10)

Author: gxkl

src/index.ts

@@ -10,6 +10,7 @@ export interface Options {
   label?: string;
   timeout?: number;
   beforeExit?: BeforeExit;
+  sigterm?: 'always' | 'once';
 }
 
 export function graceful(options: Options = {}) {
@@ -43,10 +44,23 @@ export function graceful(options: Options = {}) {
 
   // https://github.com/eggjs/egg-cluster/blob/master/lib/agent_worker.js#L35
   // exit gracefully
-  process.once('SIGTERM', () => {
-    printLogLevels.info && logger.info('[%s] receive signal SIGTERM, exiting with code:0', label);
-    exit(0);
-  });
+  if (options.sigterm === 'always') {
+    let called = false;
+    process.on('SIGTERM', () => {
+      if (called) {
+        printLogLevels.info && logger.info('[%s] receive signal SIGTERM again, waiting for exit', label);
+        return;
+      }
+      called = true;
+      printLogLevels.info && logger.info('[%s] receive signal SIGTERM, exiting with code:0', label);
+      exit(0);
+    });
+  } else {
+    process.once('SIGTERM', () => {
+      printLogLevels.info && logger.info('[%s] receive signal SIGTERM, exiting with code:0', label);
+      exit(0);
+    });
+  }
 
   process.once('exit', code => {
     const level = code === 0 ? 'info' : 'error';

test/fixtures/child.cjs

@@ -8,11 +8,19 @@ http.createServer((req, res) => {
 }).listen(8000);
 
 console.log(`Worker ${process.pid} started`);
-graceful({
+const options = {
   logger: console,
   label: 'test-child',
   logLevel: process.env.NODE_LOG_LEVEL,
-});
+};
+if (process.env.ALWAYS_ON_SIGTERM) {
+  options.sigterm = 'always';
+  options.beforeExit = async () => {
+    await new Promise(r => setTimeout(r, 1000));
+    console.log('exit after 1000ms');
+  };
+}
+graceful(options);
 
 // run again should work
 graceful();

test/fixtures/cluster.cjs

@@ -15,12 +15,22 @@ if (cluster.isMaster) {
   });
 
   process.once('SIGTERM', () => {
-    for (const id in cluster.workers) {
-      cluster.workers[id].process.kill('SIGTERM');
+    const killWorkers = () => {
+      for (const id in cluster.workers) {
+        cluster.workers[id].process.kill('SIGTERM');
+      }
+    };
+
+    killWorkers();
+
+    if (process.env.ALWAYS_ON_SIGTERM) {
+      setTimeout(killWorkers, 50);
+      setTimeout(() => process.exit(0), 2100);
+    } else {
+      setTimeout(() => {
+        process.exit(0);
+      }, 100);
     }
-    setTimeout(() => {
-      process.exit(0);
-    }, 100);
   });
 } else {
   // Workers can share any TCP connection
@@ -35,8 +45,16 @@ if (cluster.isMaster) {
 
   console.log(`Worker ${process.pid} started`);
   const { graceful } = require('../..');
-  graceful({
+  const options = {
     label: 'app-worker-' + cluster.worker.id,
     logLevel: process.env.NODE_LOG_LEVEL,
-  });
+  };
+  if (process.env.ALWAYS_ON_SIGTERM) {
+    options.sigterm = 'always';
+    options.beforeExit = async () => {
+      await new Promise(r => setTimeout(r, 1000));
+      console.log('exit after 1000ms');
+    };
+  }
+  graceful(options);
 }

test/fixtures/master-sigterm.cjs

@@ -0,0 +1,15 @@
+/* eslint-disable @typescript-eslint/no-var-requires */
+const childProcess = require('node:child_process');
+const path = require('node:path');
+
+const childFile = path.join(__dirname, 'child.cjs');
+
+const child = childProcess.fork(childFile);
+
+process.once('SIGTERM', () => {
+  child.kill('SIGTERM');
+  setTimeout(() => child.kill('SIGTERM'), 50);
+  setTimeout(() => process.exit(0), 1500);
+});
+
+console.log('master fork %s done', childFile);

test/index.test.ts

@@ -82,6 +82,28 @@ describe('test/index.test.ts', () => {
       // no exit event on coverage mode
       // child.expect('stdout', /worker \d+ died, code 0, signal null/);
     });
+
+    it('should always listen sigterm work', async () => {
+      const startFile = path.join(fixtures, 'cluster.cjs');
+      const child: any = coffee.fork(startFile, [], {
+        env: {
+          ...process.env,
+          ALWAYS_ON_SIGTERM: 'Y',
+        },
+      })
+        .debug();
+      await sleep(waitStart);
+      child.proc.kill('SIGTERM');
+      await sleep(2200);
+      if (process.platform !== 'win32') {
+        // windows can't handle SIGTERM signal
+        child.expect('stdout', /\[app-worker-\d\] receive signal SIGTERM, exiting with code:0/);
+        child.expect('stdout', /\[app-worker-\d\] receive signal SIGTERM again, waiting for exit/);
+        child.expect('stdout', /exit after 1000ms/);
+      }
+      child.expect('stdout', /\[app-worker-1\] exit with code:0/);
+      child.expect('stdout', /\[app-worker-2\] exit with code:0/);
+    });
   });
 
   describe('child_process.fork', () => {
@@ -101,6 +123,28 @@ describe('test/index.test.ts', () => {
         child.expect('stderr', /\[test-child\] exit with code:110/);
       }
     });
+
+    it('should always listen sigterm work', async () => {
+      const startFile = path.join(fixtures, 'master-sigterm.cjs');
+      const child: any = coffee.fork(startFile, [], {
+        env: {
+          ...process.env,
+          ALWAYS_ON_SIGTERM: 'Y',
+        },
+      })
+        .debug();
+      await sleep(waitStart);
+      // the worker exit by graceful-process
+      child.proc.kill('SIGTERM');
+      await sleep(2000);
+      if (process.platform !== 'win32') {
+        // windows can't handle SIGTERM signal
+        child.expect('stdout', /\[test-child\] receive signal SIGTERM, exiting with code:0/);
+        child.expect('stdout', /\[test-child\] receive signal SIGTERM again, waiting for exit/);
+        child.expect('stdout', /exit after 1000ms/);
+        child.expect('stdout', /\[test-child\] exit with code:0/);
+      }
+    });
   });
 
   describe.skip('child_process.spawn', () => {