ask for the re-authentication in api when logout from dropbox - php

Question

I am using php sdk provided by dropbox to fetch user's images.
All is working fine. When user comes to my website and clicks on the dropbox button, it is asking for the authentication first and then imports the user's images. Because of this process user automatically logs in the dropbox.com as well. It is expected behavior.
But after all this process, if user logs out from dropbox.com, and then again clicks on the dropbox button in my website, I believe my app shall ask for authentication but it does not ask for the authentication but provides the images from the user dropbox account.
Please ask for more details If I was not clear.
Thank you in advance.
Edit:
index.php
<?php
/***********************************************************************
* Plugin Name: Dropbox Plugin
* Plugin URI: http://www.picpixa.com/
* Version: 1.0
* Author: Ashish Shah
* Description: Plugin To Import Images From User's Dropbox Account
**********************************************************************/
session_start();
include_once '/home/picpixa/wp-config.php';
//ini_set("display_errors",1);
?>
<!-- Bootstrap -->
<link href='https://www.picpixa.com/wp-content/plugins/create-own-object/plugin-dropbox/css/bootstrap.css' rel='stylesheet'>
<link href='https://www.picpixa.com/wp-content/plugins/create-own-object/plugin-dropbox/css/style.css' rel='stylesheet'>
<style>
.loader {
position: fixed;
left: 0px;
top: 0px;
width: 100%;
height: 100%;
z-index: 9999;
background: url('https://www.picpixa.com/wp-content/plugins/create-own-object/plugin-dropbox/Images/page-loader.gif') 50% 50% no-repeat rgb(249,249,249);
}
</style>
<script src="//ajax.googleapis.com/ajax/libs/jquery/1.9.1/jquery.min.js"></script>
<script type="text/javascript">
$(window).load(function() {
$(".loader").fadeOut("slow");
});
//creating dynamic back button
//var docRef = document.referrer;
//$('#backBtn').html('Go Back');
//alert('Go Back');
/* Not in use
//This function will call on the click event of <div class='row'>
function loadBackBtn()
{
$('#backBtn').html('<a class="btn btn-primary" href="' + document.referrer + '">Back</a>');
}
//document.write('<a class='btn btn-primary' href="' + document.referrer + '">Back</a>');*/
</script>
<script>
function loader(){
$('#load').show();
}
/*function loadExistingImages(){
window.opener.$('#loader_img').show();
result=null;
window.opener.$('#fileupload').each(function () {
var that = this;
window.opener.$.getJSON(this.action, function (result) {
if (result && result.length) {
window.opener.$(that).fileupload('option', 'done')
.call(that, null, {result: result});
//console.log('ss='+$('.table-striped tbody').find('.btn-danger').length);
if(window.opener.$('.table-striped .files').find('.btn-danger').length>0){
window.opener.$('.coo-images-other-buttons').show();
}else{
window.opener.$('.coo-images-other-buttons').hide();
}
}
window.opener.$('#loader_img').hide();
if (window.opener.$('.table-striped.files').children().length > 0)
{
window.opener.$('.table_tagline').show();
}
});
});
}*/
</script>
<!-- Adding this block to allow to see the login page like other social media -->
<!-- Login Block Start -->
<?php /*
if(isset($_SESSION['comingFirstTime']) && $_SESSION['comingFirstTime']==true)
{
?>
<div id="load" class="loader"></div>
<div id="wrap">
<div class="header">
<h4>Dropbox</h4>
</div>
<div class="cl"></div>
<div id="middal_part">
<div class="left_side">
<img src="Images/dropbox.jpg"/>
</div>
<div class="right_side">
<a class='btn btn-primary' href="<?php echo $loginUrl ?>" onclick="loader()">Login</a><br><br>
<button class="btn btn-primary close_window" type="button" onClick="window.close();">Close</button>
</div>
<div class="cl"></div>
</div>
</div>
<?php
$_SESSION['comingFirstTime'] = false;
die;
}*/
?>
<!-- Login Block End -->
<script type="text/javascript">$('#load').hide();</script>
<?php
if(isset($_POST['copy']) && $_POST['dropbox'])
{
$imgArray = $_POST['dropbox'];
$current_user = wp_get_current_user();
if(isset($current_user->ID) && trim($current_user->ID)!='' && trim($current_user->ID)!=0){
$extraSessionStr = 'usr-'.md5($current_user->ID).'/';
$user = $current_user->ID;
}else{
$sesstionId = session_id();
$user = $sesstionId;
$extraSessionStr = $sesstionId.'/';
}
foreach ($imgArray as $img)
{
//Getting a file name
$imgInfo = pathinfo($img); //This will become an array with keys ('dirname','basename','extension','filename')
$oriFileName=$imgInfo['filename'];//Getting a file name without extension
$fileName = (string) $oriFileName.".".$imgInfo['extension'];//Creating a file name with extension
//Check weather the file is exists or not rename the file if exists
$i=1;
if(file_exists('/home/picpixa/server/php/files/'.$extraSessionStr.$fileName)){
while(file_exists('/home/picpixa/server/php/files/'.$extraSessionStr.$fileName)){
$fileName = (string) $oriFileName."(".$i.").".$imgInfo['extension'];
$i++;
}
}
// Read file content
$file_content = file_get_contents($img);
file_put_contents('/home/picpixa/server/php/files/'.$extraSessionStr.$fileName, $file_content);
//file_put_contents('/home/picpixa/server/php/thumbnails/'.$extraSessionStr.$fileName, $file_content);
/* To create thumbnail */
// Max vert or horiz resolution
$maxsize=80;
// create new Imagick object
$image = new Imagick($img); //"input_image_filename_and_location"
// Resizes to whichever is larger, width or height
if($image->getImageHeight() <= $image->getImageWidth())
{
// Resize image using the lanczos resampling algorithm based on width
$image->resizeImage($maxsize,0,Imagick::FILTER_LANCZOS,1);
}
else
{
// Resize image using the lanczos resampling algorithm based on height
$image->resizeImage(0,$maxsize,Imagick::FILTER_LANCZOS,1);
}
// Set to use jpeg compression
$image->setImageCompression(Imagick::COMPRESSION_JPEG);
// Set compression level (1 lowest quality, 100 highest quality)
$image->setImageCompressionQuality(75);
// Strip out unneeded meta data
$image->stripImage();
// Writes resultant image to output directory
$image->writeImage('/home/picpixa/server/php/thumbnails/'.$extraSessionStr.$fileName); //"output_image_filename_and_location"
// Destroys Imagick object, freeing allocated resources in the process
$image->destroy();
}
?>
<script type="text/javascript">
window.opener.$('tbody.files').find('tr').remove();
//loadExistingImages();
var myVar;
if (/(MSIE\ [0-9]{1})/i.test(navigator.userAgent)) {
window.opener.$(window.opener.loadExistingFiles());
myVar = setTimeout(function(){
window.opener.$('tbody.files').find('tr .preview a[title="<?php echo $fileName;?>"]').click();
},1000);
}
else{
window.opener.$.when(window.opener.loadExistingFiles()).done(function(){
myVar = setTimeout(function(){
window.opener.$('tbody.files').find('tr .preview a[title="<?php echo $fileName;?>"]').click();
},1000);
});
}
</script>
<?php
echo "<h2>The selected images have been uploaded successfully.</h2>";
//echo "<h3>Please click on \"Proceed With Uploaded Images\" button to Proceed OR ";
//echo "Click on the \"Upload More Images\" Button to upload more images.</h3>";
?>
<div class="modal-footer">
<input type='button' name='continue' value='Upload More Images' class='btn btn-primary' onclick='loader();window.location.href="https://www.picpixa.com/wp-content/plugins/create-own-object/plugin-dropbox/index.php/";'>
<!-- <input type='button' name='closeWindow' value='Close' class='btn btn-primary pading' onClick="window.close();"> -->
</div>
<?php
die();
}
elseif (isset($_POST['copy']))
{
echo "<h2>You have not selected any image(s) to move.</h2><br><br>";
//echo "<h3>Please click on \"Close\" button to Close the window OR ";
//echo "Click on the \"Upload Images\" Button to upload images.</h3>";
?>
<div class="modal-footer">
<input type='button' name='continue' value='Upload Images' class='btn btn-primary' onclick='loader();window.location.href="https://www.picpixa.com/wp-content/plugins/create-own-object/plugin-dropbox/index.php/";'>
<!-- <input type='button' name='closeWindow' value='Close' class='btn btn-primary pading' onClick="window.close();"> -->
</div>
<?php
die();
}
require_once __DIR__.'/dropbox-sdk/Dropbox/strict.php';
$appInfoFile = __DIR__."/AppInfo.json";
// NOTE: You should be using Composer's global autoloader. But just so these examples
// work for people who don't have Composer, we'll use the library's "autoload.php".
require_once __DIR__.'/dropbox-sdk/Dropbox/autoload.php';
use \Dropbox as dbx;
$requestPath = init();
if ($requestPath === "/") {
$dbxClient = getClient();
if ($dbxClient === false) {
$loginUrl = getPath("dropbox-auth-start");
/*$loginPage = <<<login
<div id="load" class="loader"></div>
<div id="wrap">
<div class="header">
<h4>Dropbox</h4>
<p>Display Your Photo Stream</p>
</div>
<div class="cl"></div>
<div id="middal_part">
<div class="left_side">
<img src="https://www.picpixa.com/wp-content/plugins/create-own-object/plugin-dropbox/Images/dropbox.jpg"/>
</div>
<div class="right_side">
<a class='btn btn-primary' href="$loginUrl" onclick="loader()">Login</a>
<button class="btn btn-primary close_window" type="button" onClick="window.close();">Close</button>
</div>
<div class="cl"></div>
</div>
</div>
login;*/
$loginPage = <<<login
<div id="load" class="loader"></div>
<div id="wrap">
<div class="header">
<h4>Dropbox</h4>
<p>Display Your Photo Stream</p>
</div>
<div class="cl"></div>
<div id="middal_part">
<div class="left_side">
<img src="https://www.picpixa.com/wp-content/plugins/create-own-object/plugin-dropbox/Images/dropbox.jpg"/>
</div>
<div class="right_side">
<a class='btn btn-primary' href="$loginUrl" onclick="loader()">Login</a>
</div>
<div class="cl"></div>
</div>
</div>
login;
echo $loginPage;
//header("Location: ".getPath("dropbox-auth-start"));
exit;
}
$path = "/";
if (isset($_GET['path'])) $path = $_GET['path'];
$entry = $dbxClient->getMetadataWithChildren($path);
if ($entry['is_dir']) {
echo renderFolder($entry);
}
else {
echo renderFile($entry);
}
}
else if ($requestPath == "/download") {
$dbxClient = getClient();
if ($dbxClient === false) {
header("Location: ".getPath("dropbox-auth-start"));
exit;
}
if (!isset($_GET['path'])) {
header("Location: ".getPath(""));
exit;
}
$path = $_GET['path'];
$fd = tmpfile();
$metadata = $dbxClient->getFile($path, $fd);
header("Content-Type: $metadata[mime_type]");
fseek($fd, 0);
fpassthru($fd);
fclose($fd);
}
else if ($requestPath === "/upload") {
if (empty($_FILES['file']['name'])) {
echo renderHtmlPage("Error", "Please choose a file to upload");
exit;
}
if (!empty($_FILES['file']['error'])) {
echo renderHtmlPage("Error", "Error ".$_FILES['file']['error']." uploading file. See <a href='http://php.net/manual/en/features.file-upload.errors.php'>the docs</a> for details");
exit;
}
$dbxClient = getClient();
$remoteDir = "/";
if (isset($_POST['folder'])) $remoteDir = $_POST['folder'];
$remotePath = rtrim($remoteDir, "/")."/".$_FILES['file']['name'];
$fp = fopen($_FILES['file']['tmp_name'], "rb");
$result = $dbxClient->uploadFile($remotePath, dbx\WriteMode::add(), $fp);
fclose($fp);
$str = print_r($result, TRUE);
echo renderHtmlPage("Uploading File", "Result: <pre>$str</pre>");
}
else if ($requestPath === "/dropbox-auth-start") {
$authorizeUrl = getWebAuth()->start();
header("Location: $authorizeUrl");
}
else if ($requestPath === "/dropbox-auth-finish") {
try {
list($accessToken, $userId, $urlState) = getWebAuth()->finish($_GET);
// We didn't pass in $urlState to finish, and we're assuming the session can't be
// tampered with, so this should be null.
assert($urlState === null);
}
catch (dbx\WebAuthException_BadRequest $ex) {
respondWithError(400, "Bad Request");
// Write full details to server error log.
// IMPORTANT: Never show the $ex->getMessage() string to the user -- it could contain
// sensitive information.
error_log("/dropbox-auth-finish: bad request: " . $ex->getMessage());
exit;
}
catch (dbx\WebAuthException_BadState $ex) {
// Auth session expired. Restart the auth process.
header("Location: ".getPath("dropbox-auth-start"));
exit;
}
catch (dbx\WebAuthException_Csrf $ex) {
respondWithError(403, "Unauthorized", "CSRF mismatch");
// Write full details to server error log.
// IMPORTANT: Never show the $ex->getMessage() string to the user -- it contains
// sensitive information that could be used to bypass the CSRF check.
error_log("/dropbox-auth-finish: CSRF mismatch: " . $ex->getMessage());
exit;
}
catch (dbx\WebAuthException_NotApproved $ex) {
echo renderHtmlPage("Not Authorized?", "Why not?");
exit;
}
catch (dbx\WebAuthException_Provider $ex) {
error_log("/dropbox-auth-finish: unknown error: " . $ex->getMessage());
respondWithError(500, "Internal Server Error");
exit;
}
catch (dbx\Exception $ex) {
error_log("/dropbox-auth-finish: error communicating with Dropbox API: " . $ex->getMessage());
respondWithError(500, "Internal Server Error");
exit;
}
// NOTE: A real web app would store the access token in a database.
$_SESSION['access-token'] = $accessToken;
echo renderHtmlPage("Authorized!",
"Authorization complete, <a href='".htmlspecialchars(getPath(""))."' onclick='loader()'>click here</a> to browse.");
}
else if ($requestPath === "/dropbox-auth-unlink") {
// "Forget" the access token.
unset($_SESSION['access-token']);
//$_SESSION = array();
/*echo renderHtmlPage("Logged Out",
"<div class='modal-footer'>
You have been logged out.<br>
<input type='button' name='login' value='Login Again' class='btn btn-primary' onClick='location.href = \"https://www.picpixa.com/wp-content/plugins/create-own-object/plugin-dropbox/index.php/\";'>
<input type='button' name='closeWindow' value='Close' class='btn btn-primary pading' onClick='window.close();'>
</div>"
);*/
echo renderHtmlPage("Logged Out",
"<div class='modal-footer'>
You have been logged out.<br>
<input type='button' name='login' value='Login Again' class='btn btn-primary' onClick='location.href = \"https://www.picpixa.com/wp-content/plugins/create-own-object/plugin-dropbox/index.php/\";'>
</div>"
);
}
else {
echo renderHtmlPage("Bad URL", "No handler for $requestPath");
exit;
}
function renderFolder($entry)
{
/*echo "entry:<pre>";
print_r($entry);
echo "</pre>entry end.<br>Session:<pre>";
print_r($_SESSION);
echo "</pre>Session end.";
die;*/
$dbxClient = getClient();//Using to use the createTemporaryDirectLink() function
// TODO: Add a token to counter CSRF attacks.
// $upload_path = htmlspecialchars(getPath('upload'));
//$path = htmlspecialchars($entry['path']);
//$form = <<<HTML <form action='$upload_path' method='post' enctype='multipart/form-data'> <label for='file'>Upload file:</label> <input name='file' type='file'/> <input type='submit' value='Upload'/> <input name='folder' type='hidden' value='$path'/> </form> HTML;
//$form = <<<HTML HTML;
$listing_folder = '';
$listing_folder .= "<div class='container'>
<div class='row'>
<div class='col-lg-12 col-md-12 col-sm-12 col-xs-12'>
<div style='clear: both;'></div>
<div class='modal-body'>";
$listing = "<div id='load' class='loader'></div>
<div class='container'>
<div class='row'>
<div class='col-lg-12 col-md-12 col-sm-12 col-xs-12'>
<div style='clear: both;'></div>";
/*//This section is to display logout button
if(isset($entry['contents']) && $entry['contents']){
$listing .= "<div class='modal-footer'>
<script>
function goDirect(){
window.location.href='dropbox-auth-unlink';
}
</script>
<input type='button' name='logout' value='Logout' class='btn btn-primary' onclick='goDirect()'>
</div>";
}*/
$listing .= "<form method='POST' action=''>
<div class='modal-body imgAlignment'>";
$i=0;
$showBtn=False;
foreach($entry['contents'] as $child) {
$type='Folder';
$cp = $child['path'];
$cn = basename($cp);
if (!$child['is_dir']){
$type=$child['mime_type'];
}
$cp = htmlspecialchars($cp);
$link = getPath("?path=".htmlspecialchars($cp));
if ($child['is_dir']){
$listing_folder .= "<div class='baby_img'>
<a style='text-decoration: none' href='$link'>
<img src='https://www.picpixa.com/wp-content/plugins/create-own-object/plugin-dropbox/Images/folder.jpeg' style='margin: 0px 5px 0 10px !important; width:100px !important; height:100px !important; padding: 0 5px 10px 10px !important;display: block !important;clear: left !important;float: left !important;'>
<div style='clear: both;'></div>
<p style='margin: 0px 5px 0 10px !important; padding: 0 0 0 0 !important;'>$cn</p>
</a>
</div>";
$cn .= '/';
}
else{
if(strcmp($type,'image/*')==1){
$img = $dbxClient->createTemporaryDirectLink($cp);
$listing .= "<div class='baby_img'>
<input type='checkbox' id='dropbox_".$i."' name='dropbox[]' value='".$img[0]."' class='styled' />";
$listing .= "<img src='".$img[0]."' class='img-responsive' style='width:100px !important; height:100px !important;'/>";
$listing .= '</div>';
$i++;
$showBtn=true;
}
}
}
$listing .= '<div class="clearfix"></div>
<div class="modal-footer btnAlignment">';
if($showBtn){
$listing .= "<input type='submit' name='copy' value='Copy Selected Files' class='btn btn-primary' onclick='loader();'>";
}
//$listing .= "<input type='button' name='closeWindow' value='Close This Window' class='btn btn-primary pading' onClick='window.close();'>";
$listing .= '</div>
</div>';
$listing .= "</form>
</div>
</div>
</div>";
$listing_folder .= "</div>
</div>
</div>
</div>";
return renderHtmlPage("App/picpixa$entry[path]", $listing_folder.$listing);
}
function getAppConfig()
{
global $appInfoFile;
try {
$appInfo = dbx\AppInfo::loadFromJsonFile($appInfoFile);
}
catch (dbx\AppInfoLoadException $ex) {
throw new Exception("Unable to load \"$appInfoFile\": " . $ex->getMessage());
}
$clientIdentifier = "examples-web-file-browser";
$userLocale = null;
return array($appInfo, $clientIdentifier, $userLocale);
}
function getClient()
{
if(!isset($_SESSION['access-token'])) {
return false;
}
list($appInfo, $clientIdentifier, $userLocale) = getAppConfig();
$accessToken = $_SESSION['access-token'];
return new dbx\Client($accessToken, $clientIdentifier, $userLocale, $appInfo->getHost());
}
function getWebAuth()
{
list($appInfo, $clientIdentifier, $userLocale) = getAppConfig();
$redirectUri = getUrl("dropbox-auth-finish");
$csrfTokenStore = new dbx\ArrayEntryStore($_SESSION, 'dropbox-auth-csrf-token');
return new dbx\WebAuth($appInfo, $clientIdentifier, $redirectUri, $csrfTokenStore, $userLocale);
}
function renderFile($entry)
{
$metadataStr = htmlspecialchars(print_r($entry, true));
$downloadPath = getPath("download?path=".htmlspecialchars($entry['path']));
$body = <<<HTML
<pre>$metadataStr</pre>
Download this file
HTML;
return renderHtmlPage("File: ".$entry['path'], $body);
}
function renderHtmlPage($title, $body)
{
$output = <<<HTML
<html>
<head>
<meta charset='utf-8'>
<meta http-equiv='X-UA-Compatible' content='IE=edge'>
<meta name='viewport' content='width=device-width, initial-scale=1'>
<title>$title</title>
<!-- Bootstrap -->
<link href='https://www.picpixa.com/wp-content/plugins/create-own-object/plugin-dropbox/css/bootstrap.css' rel='stylesheet'>
<link href='https://www.picpixa.com/wp-content/plugins/create-own-object/plugin-dropbox/css/style.css' rel='stylesheet'>
</head>
<body>
HTML;
$permLink = "https://www.picpixa.com/wp-content/plugins/create-own-object/plugin-dropbox/index.php/";
if(isset($_GET) && $_GET['path'] && $_GET != "/")
{
$path = $_GET['path'];
$filename = substr(strrchr($path, "/"), 1);
$newPath = $permLink."?path=".str_replace('/'.$filename,'',$path);
if($newPath == $permLink."?path="){
//Setting the newPath to the root path if there there is first folder
$newPath = $permLink;
}
$output .= "<br><div class='container'>
<div class='row'>
<div class='col-lg-12 col-md-12 col-sm-12 col-xs-12'>
<a href = '".$newPath."' class='btn btn-primary pading'>Back</a>
</div>
</div>
</div>";
}
$output .= <<<HTML
$body
</body>
</html>
HTML;
return $output;
}
function respondWithError($code, $title, $body = "")
{
$proto = $_SERVER['SERVER_PROTOCOL'];
header("$proto $code $title", true, $code);
echo renderHtmlPage($title, $body);
}
function getUrl($relative_path)
{
if (isset($_SERVER['HTTPS']) && $_SERVER['HTTPS'] !== 'off') {
$scheme = "https";
} else {
$scheme = "http";
}
$host = $_SERVER['HTTP_HOST'];
$path = getPath($relative_path);
return $scheme."://".$host.$path;
}
function getPath($relative_path)
{
if (PHP_SAPI === 'cli-server') {
return "/".$relative_path;
} else {
return $_SERVER["SCRIPT_NAME"]."/".$relative_path;
}
}
function init()
{
global $argv;
// If we were run as a command-line script, launch the PHP built-in web server.
if (PHP_SAPI === 'cli') {
launchBuiltInWebServer($argv);
assert(false);
}
if (PHP_SAPI === 'cli-server') {
// For when we're running under PHP's built-in web server, do the routing here.
return $_SERVER['SCRIPT_NAME'];
}
else {
// For when we're running under CGI or mod_php.
if (isset($_SERVER['PATH_INFO'])) {
return $_SERVER['PATH_INFO'];
} else {
return "/";
}
}
}
function launchBuiltInWebServer($argv)
{
// The built-in web server is only available in PHP 5.4+.
if (version_compare(PHP_VERSION, '5.4.0', '<')) {
fprintf(STDERR,
"Unable to run example. The version of PHP you used to run this script (".PHP_VERSION.")<br>".
"doesn't have a built-in web server. You need PHP 5.4 or newer.<br>".
"<br>".
"You can still run this example if you have a web server that supports PHP 5.3.<br>".
"Copy the Dropbox PHP SDK into your web server's document path and access it there.<br>");
exit(2);
}
$php_file = $argv[0];
if (count($argv) === 1) {
$port = 5000;
} else if (count($argv) === 2) {
$port = intval($argv[1]);
} else {
fprintf(STDERR,
"Too many arguments.<br>".
"Usage: php $argv[0] [server-port]<br>");
exit(1);
}
$host = "localhost:$port";
$cmd = escapeshellarg(PHP_BINARY)." -S ".$host." ".escapeshellarg($php_file);
$descriptors = array(
0 => array("pipe", "r"), // Process' stdin. We'll just close this right away.
1 => STDOUT, // Relay process' stdout to ours.
2 => STDERR, // Relay process' stderr to ours.
);
$proc = proc_open($cmd, $descriptors, $pipes);
if ($proc === false) {
fprintf(STDERR,
"Unable to launch PHP's built-in web server. Used command:<br>".
" $cmd<br>");
exit(2);
}
fclose($pipes[0]); // Close the process' stdin.
$exitCode = proc_close($proc); // Wait for process to exit.
exit($exitCode);
}
?>

Answer 1

"But after all this process, if user logs out from dropbox.com, and then again clicks on the dropbox button in my website, I believe my app shall ask for authentication".
Your website is remembering the user because you're using a session to do so. If you don't want to remember the user, stop doing it. :-)
In general, a user logging out of one website has no impact on their sessions at other websites. So a user logging out of dropbox.com has no effect on their logged in status on your website. Perhaps you want to set an expiration time on the session so the user is forced to reauthenticate after a while? Or you could not use a session at all (i.e. not store the access token), in which case the user would have to reauthenticate on every page load?
EDIT
Here's the code you shared that remembers the user:
if ($requestPath === "/") {
$dbxClient = getClient();
if ($dbxClient === false) {
$loginUrl = getPath("dropbox-auth-start");
...
function getClient()
{
if(!isset($_SESSION['access-token'])) {
return false;
}
list($appInfo, $clientIdentifier, $userLocale) = getAppConfig();
$accessToken = $_SESSION['access-token'];
return new dbx\Client($accessToken, $clientIdentifier, $userLocale, $appInfo->getHost());
}