added demo for persisting browser #42

CHANGELOG.md

@@ -13,7 +13,7 @@
 
 ## 0.3.0
 
-> *20xx-xx-xx* (not released)
+> *2018-08-13*
 
 > Make a crawl instance sharable among multiple scripts
 

examples/persistent-browser.php

@@ -0,0 +1,50 @@
+<?php
+
+/*
+ * This exemple shows how to share a single instance of chrome for multiple scripts.
+ *
+ * The first time the script is started we use the browser factory in order to start chrome,
+ * afterwhat we save the uri to connect to this browser in the file system.
+ *
+ * Next calls to the script will read the uri from that file in order to connect to the chrome instance instead
+ * of creating a new one. If chrome was closed or crashed, a new instance is started again.
+ */
+
+require(__DIR__ . '/../vendor/autoload.php');
+
+// path to the file to store websocket's uri
+$socketFile = '/tmp/chrome-php-demo-socket';
+
+// initialize $browser variable
+$browser = null;
+
+// try to connect to chrome instance if it exists
+if (file_exists($socketFile)) {
+    $socket =  file_get_contents($socketFile);
+
+    try {
+        $browser = \HeadlessChromium\BrowserFactory::connectToBrowser($socket, [
+            'debugLogger' => 'php://stdout'
+        ]);
+    } catch (\HeadlessChromium\Exception\BrowserConnectionFailed $e) {
+        // The browser was probably closed
+        // Keep $browser null and start it again bellow
+    }
+}
+
+// if $browser is null then create a new chrome instance
+if (!$browser) {
+    $factory = new \HeadlessChromium\BrowserFactory();
+    $browser = $factory->createBrowser([
+        'headless' => false,
+        'keepAlive' => true
+    ]);
+
+    // save the uri to be able to connect again to browser
+    file_put_contents($socketFile, $browser->getSocketUri());
+}
+
+// do something with the browser
+$page = $browser->createPage();
+
+$page->navigate('http://example.com')->waitForNavigation();