using standard logging library, reuse session for performance

Author: smithclay

examples/visitgoogle.js

@@ -11,5 +11,5 @@ $browser.findElement($driver.By.name('btnK')).click();
 $browser.wait($driver.until.titleIs('Google'), 1000);
 $browser.getTitle().then(function(title) {
     console.log("title is: " + title);
+    console.log('Finished running script!');
 });
-console.log('Finished running script!');

index.js

@@ -4,26 +4,33 @@ const fs = require('fs');
 
 const chromium = require('./lib/chromium');
 const sandbox = require('./lib/sandbox');
-const { log } = require('./lib/helpers');
+const log = require('lambda-log');
 
-console.log('Loading function');
+log.info('Loading function');
+
+// Create new session (spawns chromium and webdriver)
+$browser = chromium.createSession();
 
 exports.handler = (event, context, callback) => {
   context.callbackWaitsForEmptyEventLoop = false;
 
-  if (process.env.CLEAR_TMP) {
-    log('attempting to clear /tmp directory')
-    log(child.execSync('rm -rf /tmp/core*').toString());
+  /*if (process.env.CLEAR_TMP) {
+    log.info('attempting to clear /tmp directory')
+    log.info(child.execSync('rm -rf /tmp/core*').toString());
+  }*/
+
+  if (process.env.DEBUG_ENV || process.env.SAM_LOCAL) {
+    log.config.debug = true;
+    log.config.dev = true;
   }
 
-  if (process.env.DEBUG_ENV) {
-    //log(child.execSync('set').toString());
-    log(child.execSync('pwd').toString());
-    log(child.execSync('ls -lhtra .').toString());
-    log(child.execSync('ls -lhtra /tmp').toString());
+  if (process.env.LOG_DEBUG) {
+    log.debug(child.execSync('pwd').toString());
+    log.debug(child.execSync('ls -lhtra .').toString());
+    log.debug(child.execSync('ls -lhtra /tmp').toString());  
   }
 
-  log('Received event:', JSON.stringify(event, null, 2));
+  log.info(`Received event: ${JSON.stringify(event, null, 2)}`);
 
   // Read input
   const inputParam = event.Base64Script || process.env.BASE64_SCRIPT;
@@ -32,17 +39,13 @@ exports.handler = (event, context, callback) => {
   }
 
   const inputBuffer = Buffer.from(inputParam, 'base64').toString('utf8');
-  if (process.env.DEBUG_ENV) {
-    log(`Executing "${inputBuffer}"`);
-  }
+  log.debug(`Executing script "${inputBuffer}"`);
 
-  // Start selenium webdriver session
-  $browser = chromium.createSession();
   sandbox.executeScript(inputBuffer, $browser, webdriver, function(err) {
-    if (process.env.DEBUG_ENV) {
-      log(child.execSync('ps aux').toString());
+    if (process.env.LOG_DEBUG) {
+      log.debug(child.execSync('ps aux').toString());
+      log.debug(child.execSync('cat /tmp/chromedriver.log').toString())
     }
-
     if (err) {
       callback(err, null);
     }

lib/chromium.js

@@ -1,5 +1,4 @@
 const child = require('child_process');
-const { log } = require('./helpers');
 const os = require('os');
 const path = require('path');
 const chrome = require('selenium-webdriver/chrome');
@@ -44,9 +43,15 @@ const defaultChromeFlags = [
 const HEADLESS_CHROME_PATH = 'bin/headless-chromium';
 const CHROMEDRIVER_PATH = '/var/task/bin/chromedriver';
 exports.createSession = function() {
-  const service = new chrome.ServiceBuilder(CHROMEDRIVER_PATH)
-    .enableVerboseLogging()
-    .build();
+  var service;
+  if (process.env.LOG_DEBUG || process.env.SAM_LOCAL) {
+    service = new chrome.ServiceBuilder(CHROMEDRIVER_PATH)
+      .loggingTo('/tmp/chromedriver.log')
+      .build();
+  } else {
+    service = new chrome.ServiceBuilder(CHROMEDRIVER_PATH)
+      .build();
+  }
 
   const options = new chrome.Options();
 
@@ -60,16 +65,3 @@ exports.createSession = function() {
   return chrome.Driver.createSession(options, service);
 }
 
-const spawnProcess = function(localPath, flags) {
-  const opts = {
-      cwd: os.tmpdir(),
-      shell: true,
-      detached: true,
-  };
-
-  const proc = child.spawn(path.join(process.env.LAMBDA_TASK_ROOT, localPath), 
-    flags,
-    opts
-  );
-  return proc; 
-};

lib/helpers.js

@@ -1,4 +1,5 @@
 const vm = require('vm');
+const log = require('lambda-log');
 
 exports.executeScript = function(scriptText, browser, driver, cb) {
   // Create Sandbox VM
@@ -14,7 +15,7 @@ exports.executeScript = function(scriptText, browser, driver, cb) {
   try {
     script.runInContext(scriptContext);
   } catch (e) {
-    console.log('[script error]', e);
+    log.error(`[script error] ${e}`);
     return cb(e, null);
   } 
 
@@ -27,8 +28,13 @@ exports.executeScript = function(scriptText, browser, driver, cb) {
       }
   });
   */
-
-  $browser.quit().then(function() {
-    cb(null);
+  // https://github.com/GoogleChrome/puppeteer/issues/1825#issuecomment-372241101
+  // Reuse existing session, likely some edge cases around this...
+  browser.manage().deleteAllCookies().then(function() {
+    return $browser.get('about:blank').then(function() {
+      cb(null);
+    }).catch(function(err) {
+      cb(err);
+    });
   });
 }

lib/sandbox.js

@@ -1,6 +1,6 @@
 {
   "name": "lambdium",
-  "version": "0.1.0",
+  "version": "0.1.1",
   "description": "headless chromium in lambda prototype",
   "main": "index.js",
   "scripts": {
@@ -9,6 +9,7 @@
   "author": "Clay Smith",
   "license": "ISC",
   "dependencies": {
+    "lambda-log": "^1.3.0",
     "selenium-webdriver": "^3.6.0"
   }
 }

package-lock.json

@@ -9,10 +9,9 @@ Resources:
       Runtime: nodejs6.10
       FunctionName: lambdium
       Description: headless chromium running selenium
-      MemorySize: 1024
-      Timeout: 10
+      MemorySize: 1156
+      Timeout: 20
       Environment:
         Variables:
-          DEBUG_ENV: "true"
           CLEAR_TMP: "true"
       CodeUri: .