spider - crawling headless browser client

index.js

@@ -2,8 +2,10 @@ const express = require("express")
     , expressLogging = require("express-logging")
     , logger = require("logops")
     , hostname = require('os').hostname()
-    , browser = require('./HeadlessBrowser')
-    , port = 32023;
+    , browser = require('./src/service/HeadlessService')
+    , port = 32101
+    , { NoSuchSessionError } = require("selenium-webdriver/lib/error")
+    // , { puppeteerErrors } = require("puppeteer-core/lib/cjs/puppeteer/common/Errors");
 
 
 logger.getContext = function getContext() {
@@ -21,6 +23,58 @@ app.listen(port, () => {
     logger.info({ app: 'Headless browser' }, 'Startup');
 });
 
+
+// process.stdin.resume();//so the program will not close instantly
+
+exitHandler = (options, exitCode) => {
+    if (options.cleanup) logger.info('cleanup')
+    if (exitCode || exitCode === 0) logger.info('exit code :', exitCode)
+    browser.close().then(() => process.exit());
+}
+
+/**
+ * Process shutdown events handling
+ */
+//do something when app is closing
+process.on('exit', exitHandler.bind(null, { cleanup: true }));
+
+//catches ctrl+c event
+process.on('SIGINT', exitHandler.bind(null, { exit: true }));
+
+process.on('SIGTERM', exitHandler.bind(null, { cleanup: true }));
+
+// setTimeout(() => {
+//     process.on('SIGKILL', exitHandler.bind(null, {exit:true}));
+// }, 2000)
+
+
+// catches "kill pid" (for example: nodemon restart)
+// process.on('SIGUSR1', exitHandler.bind(null, {exit:true}));
+// process.on('SIGUSR2', exitHandler.bind(null, {exit:true}));
+
+//catches uncaught exceptions
+// process.on('uncaughtException', exitHandler.bind(null, {exit:true}));
+
+/**
+ * request handler
+ */
 app.post('/', async (req, res, next) => {
-    browser.real(req.body.url).then(html => res.send(html))
+    const requestPage = () => browser.real(req.body.url).then(html => res.send(html)).catch(e => {
+        if(e instanceof NoSuchSessionError) {
+            browser.reset()
+            logger.error({ reason: e.message, url: req.url }, 'Browser session expired')
+        }else {
+            logger.error({ reason: e.message, url: req.url }, 'Browser error occured')
+        }        
+        res.status(500).send({ code: 500, message: e.message })
+        // browser.close().then(() => e instanceof puppeteerErrors.TimeoutError ? setTimeout(() => requestPage(), 3000) : res.status(500).send(e.message))
+    })
+    requestPage()
+})
+
+app.get('/restart', (req, res, next) => {
+    // browser.close().then(() => {
+    //     res.json({message: 'Browser closed and lanuch with new request'})
+    // })
+    process.exit()    
 })