fix(server.js): terminate http server process gracefully (#313)

* fix(server.js): refuse new request and finish the current one before exit(0)
* fix: hmr and cleanup
* fix: use http-graceful-shutdown to terminate server process
* fix: set timeout before SIGKILL to 15 seconds

config/utils/killProcess.js

@@ -1,14 +1,14 @@
 const ALLOWED_SIGNALS = ['SIGTERM', 'SIGINT', 'SIGQUIT'];
 
-export default (process, { signal = 'SIGTERM', timeout = 4000 } = {}) => {
+export default (process, { signal = 'SIGTERM', timeout = 15000 } = {}) => {
     if (!ALLOWED_SIGNALS.includes(signal)) {
         throw new Error(`Invalid signal: "${signal}", expecting one of ${ALLOWED_SIGNALS.join()}`);
     }
 
     return new Promise((resolve) => {
         const killTimeout = setTimeout(() => {
             // eslint-disable-next-line no-console
-            console.warn('[Vitamin] Server timeout: sending SIGKILL...');
+            console.warn('[Vitamin] Process timeout: sending SIGKILL...');
             process.kill('SIGKILL');
         }, timeout);
 

package.json

@@ -68,6 +68,7 @@
     "file-loader": "^0.11.1",
     "friendly-errors-webpack-plugin": "^1.6.1",
     "history": "^3.2.1",
+    "http-graceful-shutdown": "^1.0.6",
     "isomorphic-style-loader": "^1.1.0",
     "js-string-escape": "^1.0.1",
     "json-loader": "^0.5.4",

src/server/components/DivLayout.jsx

@@ -1,3 +1,5 @@
+/* eslint react/no-danger: 0 */
+
 import { PropTypes } from 'react';
 
 const propTypes = {

src/server/components/HTMLLayout.jsx

@@ -1,3 +1,5 @@
+/* eslint react/no-danger: 0 */
+
 import { PropTypes } from 'react';
 
 const HelmetHeadPropTypes = PropTypes.shape({

src/server/middlewares/errorHandler.jsx

@@ -47,13 +47,13 @@ const onError = (errorContext) => {
         console.error(chalk.red.bold(errorContext.error.message));
         console.error(chalk.grey(errorContext.error.stack));
     }
-    /* eslint-enable no-console */
     try {
         userOnError(errorContext);
     } catch (err) {
         console.error(chalk.red('An error occured while calling the onError function'));
         console.error(err);
     }
+    /* eslint-enable no-console */
 };
 
 const errorToErrorContext = (ctx, error) => ({

src/server/server.js

@@ -6,29 +6,30 @@ import express from 'express';
 import chalk from 'chalk';
 import fetch from 'node-fetch';
 import readline from 'readline';
+import httpGracefulShutdown from 'http-graceful-shutdown';
 
-import app from './app';
+import appMiddleware from './appMiddleware';
 import config from '../../config';
 import webpackClientConfig from '../../config/build/webpack.config.client';
 
 global.fetch = fetch;
 
-let currentApp = app;
+let currentApp = appMiddleware;
 function appServer() {
-    const server = new Koa();
-    server.use(
+    const app = new Koa();
+    app.use(
         process.env.NODE_ENV === 'production' ? currentApp
             // ecapsulate app for hot reload
             : (ctx, next) => currentApp(ctx, next),
     );
-    return server.callback();
+    return app.callback();
 }
 
 const mountedServer = express();
 
 if (process.env.NODE_ENV !== 'production' && module.hot) {
     const hotReloadServer = () => {
-        const server = express();
+        const app = express();
         const webpack = require('webpack');
         const clientBuildConfig = webpackClientConfig({
             hot: true,
@@ -39,7 +40,7 @@ if (process.env.NODE_ENV !== 'production' && module.hot) {
         const compiler = webpack(clientBuildConfig);
         let clientBuilt = false;
         const parsedPublicPath = parseUrl(config.publicPath).pathname || '';
-        server.use(require('webpack-dev-middleware')(compiler, {
+        app.use(require('webpack-dev-middleware')(compiler, {
             quiet: true,
             noInfo: true,
             publicPath: parsedPublicPath,
@@ -56,19 +57,19 @@ if (process.env.NODE_ENV !== 'production' && module.hot) {
         }));
 
         const hmrPath = `${parsedPublicPath}/__webpack_hmr`;
-        server.use(require('webpack-hot-middleware')(compiler, {
+        app.use(require('webpack-hot-middleware')(compiler, {
             log: () => {},
             path: hmrPath,
             reload: true,
         }));
 
-        return server;
+        return app;
     };
 
     mountedServer.use(hotReloadServer());
-    module.hot.accept('./app', () => {
+    module.hot.accept('./appMiddleware', () => {
         try {
-            currentApp = require('./app').default;
+            currentApp = require('./appMiddleware').default;
         } catch (e) {
             console.error(e);
         }
@@ -78,7 +79,7 @@ if (process.env.NODE_ENV !== 'production' && module.hot) {
 const { port, host } = config.server;
 mountedServer.use(config.basePath, appServer());
 
-mountedServer.listen(process.env.PORT || port, process.env.HOST || host, () => {
+const server = mountedServer.listen(process.env.PORT || port, process.env.HOST || host, () => {
     readline.clearLine(process.stdout);
     readline.cursorTo(0, process.stdout);
     process.stdout.write(`\x1b[0G${chalk.green('\u2713')} Server listening on: ${
@@ -92,3 +93,11 @@ mountedServer.listen(process.env.PORT || port, process.env.HOST || host, () => {
     }
 });
 
+httpGracefulShutdown(server, {
+    signals: 'SIGINT SIGTERM SIGQUIT',
+    timeout: 15000,
+    development: process.env.NODE_ENV !== 'production',
+    callback: () => {
+        process.stdout.write('Server gracefully terminated.');
+    },
+});

yarn.lock

@@ -2442,6 +2442,13 @@ http-errors@~1.5.0:
     setprototypeof "1.0.2"
     statuses ">= 1.3.1 < 2"
 
+http-graceful-shutdown@^1.0.6:
+  version "1.0.6"
+  resolved "https://registry.yarnpkg.com/http-graceful-shutdown/-/http-graceful-shutdown-1.0.6.tgz#26314e3e1ca812f1acba243d05cbc0965a8f17f6"
+  dependencies:
+    debug "^2.2.0"
+    lodash "^4.1.0"
+
 http-signature@~1.1.0:
   version "1.1.1"
   resolved "https://registry.yarnpkg.com/http-signature/-/http-signature-1.1.1.tgz#df72e267066cd0ac67fb76adf8e134a8fbcf91bf"