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+# Integration of XHProf profiler to the OpenSILEX WebApp (use case: export of all scientific objects)
+
+## I/ Prerequisite
+- 1/ [XHProf-Tideways extension](https://github.com/tideways/php-xhprof-extension.git)
+
+- 2/ [Tideways Toolkit (tk)](https://github.com/tideways/toolkit.git) *A collection of commandline tools*
+
+
+- 3/ [Graphviz](https://doc.ubuntu-fr.org/graphviz) *Graph Visualization Software*
+
+
+<br>
+
+
+## 1/ Installation of XHProf-Tideways 
+
+XHProf is a profiler designed to analyze PHP applications. Initially created and open sourced by Facebook (compatible with php5). Tideways company maintain a fork of the original XHProf extension that provides PHP 7 support [Tideways XHProf extension](https://github.com/tideways/php-xhprof-extension.git).
+
+
+### Install the server Dependencies
+
+
+
+```console
+user@phis:~$ sudo apt install php7.0-dev
+
+//install the extension from source
+user@phis:~$ git clone https://github.com/tideways/php-xhprof-extension.git
+user@phis:~$ cd php-xhprof-extension/
+user@phis:~$ phpize
+user@phis:~$ ./configure
+user@phis:~$ make
+user@phis:~$ sudo make install
+```
+
+Include the following contents in the php.ini file:
+```
+extension=tideways_xhprof.so
+```
+Restart Apache
+```console
+user@phis:~$ sudo systemctl restart apache2
+```
+
+
+## 2/ Installation of Tideways Toolkit (tk)  
+
+### Prerequisite
+- [Go](https://golang.org/dl/) *Tideways Toolkit is written in Go and you can install it with the Go compiler*
+
+```console
+user@phis:~$ go get github.com/tideways/toolkit
+```
+
+You will then find the compiled binary in ```/home/$USER/code/golang/bin/toolkit``` and can copy or symlink it to ```/usr/local/bin/tk```
+</br>
+
+
+## 3/ Installation of Graphviz
+```console
+user@phis:~$ sudo apt install graphviz
+```
+</br>
+</br>
+
+## II/ Profilling OpenSILEX webapp (export of scientific objects use case)
+
+### Code source integration
+
+Add the fellowing instructions to enable and disable the profiler
+
+```php
+if (extension_loaded('tideways_xhprof')) {
+    tideways_xhprof_enable(TIDEWAYS_XHPROF_FLAGS_MEMORY | TIDEWAYS_XHPROF_FLAGS_CPU);
+}
+```
+
+
+```php
+if (extension_loaded('tideways_xhprof')) {
+    $data = tideways_xhprof_disable();
+    file_put_contents(
+        sys_get_temp_dir() . "/ScientificObjectController_profiling.xhprof",
+        json_encode($data)
+        );
+}
+```
+
+In this case we enable the profiler when starting export of scientific objects and disable it before sending the result.
+
+```php
+<?php
+/*
+phis-webapp/controllers/ScientificObjectController.php 
+*/
+public function actionDownloadCsv() {
+
+//---------->>>>>>>>>> XHProf integration
+if (extension_loaded('tideways_xhprof')) {
+    tideways_xhprof_enable(TIDEWAYS_XHPROF_FLAGS_MEMORY | TIDEWAYS_XHPROF_FLAGS_CPU);
+}
+//----------<<<<<<<<<<
+
+
+$searchModel = new ScientificObjectSearch();
+if (isset($_GET['model'])) {
+    $searchParams = $_GET['model'];
+    $searchModel->label = isset($searchParams["alias"]) ? $searchParams["alias"] : null;  //why alias ? and not label , c'est quoi l'alias ?
+    $searchModel->type = isset($searchParams["type"]) ? $searchParams["type"] : null;
+    $searchModel->experiment = isset($searchParams["experiment"]) ? $searchParams["experiment"] : null;
+}
+$searchParams = []; // ???
+// Set page size to 10000 for better performances
+$searchModel->pageSize = 10000;
+//get all the data (if multiple pages) and write them in a file
+$serverFilePath = \config::path()['documentsUrl'] . "AOFiles/exportedData/" . time() . ".csv";
+$stringToWrite = "ScientificObjectURI" . Yii::$app->params['csvSeparator'] .
+        "Alias" . Yii::$app->params['csvSeparator'] .
+        "RdfType" . Yii::$app->params['csvSeparator'] .
+        "ExperimentURI" . Yii::$app->params['csvSeparator'] .
+        "Geometry" .
+        "\n";
+$totalPage = 1;
+for ($i = 0; $i < $totalPage; $i++) {
+    //1. call service for each page
+    $searchParams["page"] = $i;
+    $searchResult = $searchModel->search(Yii::$app->session['access_token'], $searchParams);
+    //2. write in file
+    $models = $searchResult->getmodels();
+    foreach ($models as $model) {
+        // Parse geoJson geometry to WKT if exists
+        $geoJson = $model->geometry;
+        if ($geoJson != null) {
+            $geom = \geoPHP::load($model->geometry, 'json');
+            $wktGeometry = (new \WKT())->write($geom);
+        } else {
+            $wktGeometry = "";
+        }
+
+        $stringToWrite .= $model->uri . Yii::$app->params['csvSeparator'] . 
+                            $model->label . Yii::$app->params['csvSeparator'] .
+                            $model->rdfType . Yii::$app->params['csvSeparator'] .
+                            $model->experiment . Yii::$app->params['csvSeparator'] . 
+                            '"' . $wktGeometry . '"' . Yii::$app->params['csvSeparator'] . 
+                            "\n";
+    }
+    $totalPage = intval($searchModel->totalPages);
+}
+file_put_contents($serverFilePath, $stringToWrite, FILE_APPEND);
+
+//---------->>>>>>>>>> XHProf integration
+if (extension_loaded('tideways_xhprof')) {
+    $data = tideways_xhprof_disable();
+    file_put_contents(
+        sys_get_temp_dir() . "/ScientificObjectController_profiling.xhprof",
+        json_encode($data)
+        );
+}
+//----------<<<<<<<<<<
+
+Yii::$app->response->sendFile($serverFilePath);
+}
+
+
+```
+
+### Generation of callgraph visualization
+```console
+user@phis:~$ cd /tmp
+user@phis:~$ tk generate-xhprof-graphviz ScientificObjectController_profiling.xhprof
+```
+
+
+### Convert callgraph to a viewable image
+```console
+user@phis:~$ dot -Tpng callgraph.dot > callgraph.png
+```
+
+callgraph.png
+<img src="img/callgraph.png"/>
+
+
+
+
+
+	
+
+    
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