#3 working with data stored in files && securing your application
This chapter reveals that you can use files and databases together to build PHP application that waash in binary data.
The application needs to store images.
Firstly, we should use the ALTER statement to change the structure of a database.
ALTER TABLE guitarwars
ADD COLUMN screeshot varchar(64)
Next step, we should understand how can we get an image from the user ?
<input type="file" id="screenshot" name="screenshot" />
This can use a file input field to allow image file uploads.
Then we should Insert the data posted from the form into the table, use the INSERT statment :
INSERT INTO guitarwars VALUES
(0, NOW(), '$name', '$score', '$screenshot')
Here we just need to insert the filename into the table , so $screenshot represents the name of the file
the super variable $_FILES is where PHP stores infomation about an uploaded file.
$screenshot = $_FILES['screenshot']['name']
// some other attributes :
$_FILES['screenshot']['type']
$_FILES['screenshot']['size']
$_FILES['screenshot']['tmp_name']
$_FILES['screenshot']['error']
you may have a question why dont just store the image file into the database ?
Databases excel at storing text data, not raw binary data such as images. so its better to just store a reference to an image in the database .
This reference is the name of the image file.
Another reason is beacese it would be much harderto display them using HTML code. You can see that generating an image tag
in HTML involves using an image filename, not raw image data. just like :
<img src = "phizsscore.jpg" alt = "Score image" />
Here is another question, when we uploads the file, where did they go ?
The answer is the file is actually uploaded to a temporary folder on the server. The temporary folder is created automatically on the server
and usually has a weird name with a bunch of random letter and numbers.
If we want to use the files again, we should control the initial storage location of uploaded files in PHP.
You can move file from the temporary folder to a permanenet folder by using this function :
move_uploaded_file( $_FILES['screenshot']['name'], $target) ;
$target is the destination location where you want to put the file on server .
Every Application needs a image folder. so create a home for uploaded iamge files.
$target = GW_UPLOADPATH.$screenshot ;
There is another problem, if two users uploaded image file with the same filenames, it will overwrite the one before.
A simple way to solve this is to add current server time to the front of the filename:
$target = GW_UPLOADPATH. time() . $screenshot
Just a tips here : If your PHP App is hosted anywhere other than your local computer, you'll need to use FTP to
create the images folder on the server.
If the path changes, you have to change the code in all places, so you can use define() to avoid this :
define('GW_UPLOADPATH', 'images/')
and if you want to access the constants in other scripts, you may use the require_once()
require_once('appvars.php');
Just think of require_onece as "insert" . This statement inserts shared script code into other scripts.
We almost finish our application. But if this would be a real appliaction, is needs the VALIDATION .
Validation on the image file serves two vitial purposes. 1, it can beef up the prevention of large file uploads, providing users with notification that
a file cant be larger than 32kb. 2, it can stop people from uploading files that aren't images. try the code below:
if (
( ($screenshot_type == 'image/gif') || ($screenshot_type=='image/jpeg')
||($screenshot_type == 'image/pjpeg') || ($screenshot_type == 'image/png'))
&& ($screenshot_size > 0) && ($screenshot_size <= GW_MAXFILESIZE)
) {
...
}
IN the real application, we often need some function groups and pages which can only be used by the admin, so the administrator
can manage this application. We will add an admin model in this app too.
The project files are as follows :
/**** index.php **** /
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>Guitar Wars - High Scores</title>
<link rel="stylesheet" type="text/css" href="style.css" />
</head>
<body>
<h2>Guitar Wars - High Scores</h2>
<p>Welcome, Guitar Warrior, do you have what it takes to crack the high score list? If so, just <a href="addscore.php">add your own score</a>.</p>
<hr /> <?php
require_once('appvars.php');
require_once('connectvars.php'); // Connect to the database
$dbc = mysqli_connect(DB_HOST, DB_USER, DB_PASSWORD, DB_NAME); // Retrieve the score data from MySQL
$query = "SELECT * FROM guitarwars ORDER BY score DESC, date ASC";
$data = mysqli_query($dbc, $query); // Loop through the array of score data, formatting it as HTML
echo '<table>';
$i = 0;
while ($row = mysqli_fetch_array($data)) {
// Display the score data
if ($i == 0) {
echo '<tr><td colspan="2" class="topscoreheader">Top Score: ' . $row['score'] . '</td></tr>';
}
echo '<tr><td class="scoreinfo">';
echo '<span class="score">' . $row['score'] . '</span><br />';
echo '<strong>Name:</strong> ' . $row['name'] . '<br />';
echo '<strong>Date:</strong> ' . $row['date'] . '</td>';
if (is_file(GW_UPLOADPATH . $row['screenshot']) && filesize(GW_UPLOADPATH . $row['screenshot']) > 0) {
echo '<td><img src="' . GW_UPLOADPATH . $row['screenshot'] . '" alt="Score image" /></td></tr>';
}
else {
echo '<td><img src="' . GW_UPLOADPATH . 'unverified.gif' . '" alt="Unverified score" /></td></tr>';
}
$i++;
}
echo '</table>'; mysqli_close($dbc);
?> </body>
</html>
/**** addscore.php ****/
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>Guitar Wars - Add Your High Score</title>
<link rel="stylesheet" type="text/css" href="style.css" />
</head>
<body>
<h2>Guitar Wars - Add Your High Score</h2> <?php
require_once('appvars.php');
require_once('connectvars.php'); if (isset($_POST['submit'])) {
// Grab the score data from the POST
$name = $_POST['name'];
$score = $_POST['score'];
$screenshot = $_FILES['screenshot']['name'];
$screenshot_type = $_FILES['screenshot']['type'];
$screenshot_size = $_FILES['screenshot']['size']; if (!empty($name) && !empty($score) && !empty($screenshot)) {
if ((($screenshot_type == 'image/gif') || ($screenshot_type == 'image/jpeg') || ($screenshot_type == 'image/pjpeg') || ($screenshot_type == 'image/png'))
&& ($screenshot_size > 0) && ($screenshot_size <= GW_MAXFILESIZE)) {
if ($_FILES['screenshot']['error'] == 0) {
// Move the file to the target upload folder
$target = GW_UPLOADPATH . $screenshot;
if (move_uploaded_file($_FILES['screenshot']['tmp_name'], $target)) {
// Connect to the database
$dbc = mysqli_connect(DB_HOST, DB_USER, DB_PASSWORD, DB_NAME); // Write the data to the database
$query = "INSERT INTO guitarwars VALUES (0, NOW(), '$name', '$score', '$screenshot')";
mysqli_query($dbc, $query); // Confirm success with the user
echo '<p>Thanks for adding your new high score! It will be reviewed and added to the high score list as soon as possible.</p>';
echo '<p><strong>Name:</strong> ' . $name . '<br />';
echo '<strong>Score:</strong> ' . $score . '<br />';
echo '<img src="' . GW_UPLOADPATH . $screenshot . '" alt="Score image" /></p>';
echo '<p><a href="index.php"><< Back to high scores</a></p>'; // Clear the score data to clear the form
$name = "";
$score = "";
$screenshot = ""; mysqli_close($dbc);
}
else {
echo '<p class="error">Sorry, there was a problem uploading your screen shot image.</p>';
}
}
}
else {
echo '<p class="error">The screen shot must be a GIF, JPEG, or PNG image file no greater than ' . (GW_MAXFILESIZE / 1024) . ' KB in size.</p>';
} // Try to delete the temporary screen shot image file
@unlink($_FILES['screenshot']['tmp_name']);
}
else {
echo '<p class="error">Please enter all of the information to add your high score.</p>';
}
}
?> <hr />
<form enctype="multipart/form-data" method="post" action="<?php echo $_SERVER['PHP_SELF']; ?>">
<input type="hidden" name="MAX_FILE_SIZE" value="<?php echo GW_MAXFILESIZE; ?>" />
<label for="name">Name:</label>
<input type="text" id="name" name="name" value="<?php if (!empty($name)) echo $name; ?>" /><br />
<label for="score">Score:</label>
<input type="text" id="score" name="score" value="<?php if (!empty($score)) echo $score; ?>" /><br />
<label for="screenshot">Screen shot:</label>
<input type="file" id="screenshot" name="screenshot" />
<hr />
<input type="submit" value="Add" name="submit" />
</form>
</body>
</html>
/**** appvars.php ****/
<?php
// Define application constants
define('GW_UPLOADPATH', 'images/');
define('GW_MAXFILESIZE', 32768); // 32 KB
?>
/**** connectvars.php ****/
<?php
// Define database connection constants
define('DB_HOST', 'localhost');
define('DB_USER', 'root');
define('DB_PASSWORD', 'root');
define('DB_NAME', 'gwdb');
?>
About the adminuser, you can visit the admin model by : localhost/...path/guitarwars/admin.php
/**** admin.php ****/
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>Guitar Wars - High Scores Administration</title>
<link rel="stylesheet" type="text/css" href="style.css" />
</head>
<body>
<h2>Guitar Wars - High Scores Administration</h2>
<p>Below is a list of all Guitar Wars high scores. Use this page to remove scores as needed.</p>
<hr /> <?php
require_once('appvars.php');
require_once('connectvars.php'); // Connect to the database
$dbc = mysqli_connect(DB_HOST, DB_USER, DB_PASSWORD, DB_NAME); // Retrieve the score data from MySQL
$query = "SELECT * FROM guitarwars ORDER BY score DESC, date ASC";
$data = mysqli_query($dbc, $query); // Loop through the array of score data, formatting it as HTML
echo '<table>';
while ($row = mysqli_fetch_array($data)) {
// Display the score data
echo '<tr class="scorerow"><td><strong>' . $row['name'] . '</strong></td>';
echo '<td>' . $row['date'] . '</td>';
echo '<td>' . $row['score'] . '</td>';
echo '<td><a href="removescore.php?id=' . $row['id'] . '&date=' . $row['date'] .
'&name=' . $row['name'] . '&score=' . $row['score'] .
'&screenshot=' . $row['screenshot'] . '">Remove</a></td></tr>';
}
echo '</table>'; mysqli_close($dbc);
?> </body>
</html>
/**** removescore.php ****/
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>Guitar Wars - Remove a High Score</title>
<link rel="stylesheet" type="text/css" href="style.css" />
</head>
<body>
<h2>Guitar Wars - Remove a High Score</h2> <?php
require_once('appvars.php');
require_once('connectvars.php'); if (isset($_GET['id']) && isset($_GET['date']) && isset($_GET['name']) && isset($_GET['score']) && isset($_GET['screenshot'])) {
// Grab the score data from the GET
$id = $_GET['id'];
$date = $_GET['date'];
$name = $_GET['name'];
$score = $_GET['score'];
$screenshot = $_GET['screenshot'];
}
else if (isset($_POST['id']) && isset($_POST['name']) && isset($_POST['score'])) {
// Grab the score data from the POST
$id = $_POST['id'];
$name = $_POST['name'];
$score = $_POST['score'];
}
else {
echo '<p class="error">Sorry, no high score was specified for removal.</p>';
} if (isset($_POST['submit'])) {
if ($_POST['confirm'] == 'Yes') {
// Delete the screen shot image file from the server
@unlink(GW_UPLOADPATH . $screenshot); // Connect to the database
$dbc = mysqli_connect(DB_HOST, DB_USER, DB_PASSWORD, DB_NAME); // Delete the score data from the database
$query = "DELETE FROM guitarwars WHERE id = $id LIMIT 1";
mysqli_query($dbc, $query);
mysqli_close($dbc); // Confirm success with the user
echo '<p>The high score of ' . $score . ' for ' . $name . ' was successfully removed.';
}
else {
echo '<p class="error">The high score was not removed.</p>';
}
}
else if (isset($id) && isset($name) && isset($date) && isset($score)) {
echo '<p>Are you sure you want to delete the following high score?</p>';
echo '<p><strong>Name: </strong>' . $name . '<br /><strong>Date: </strong>' . $date .
'<br /><strong>Score: </strong>' . $score . '</p>';
echo '<form method="post" action="removescore.php">';
echo '<input type="radio" name="confirm" value="Yes" /> Yes ';
echo '<input type="radio" name="confirm" value="No" checked="checked" /> No <br />';
echo '<input type="submit" value="Submit" name="submit" />';
echo '<input type="hidden" name="id" value="' . $id . '" />';
echo '<input type="hidden" name="name" value="' . $name . '" />';
echo '<input type="hidden" name="score" value="' . $score . '" />';
echo '</form>';
} echo '<p><a href="admin.php"><< Back to admin page</a></p>';
?> </body>
</html>
At last, some css styles :
.error {
font-weight: bold;
color: #FF0000;
}
.topscoreheader {
text-align: center;
font-size: 200%;
background-color: #36407F;
color: #FFFFFF;
}
.score {
font-size:150%;
color: #36407F;
}
.scoreinfo {
vertical-align: top;
padding-right:15px;
}
#3 working with data stored in files && securing your application的更多相关文章
- #3 working with data stored in files && securing your application (PART II)
Security problems is more and more important on the internet today. You can see the problems . This ...
- Enabling granular discretionary access control for data stored in a cloud computing environment
Enabling discretionary data access control in a cloud computing environment can begin with the obtai ...
- 安装mysql时出现initialize specified but the data directory has files in in.Aborting.该如何解决
eclipse中写入sql插入语句时,navicat中显示的出现乱码(???). 在修改eclipse工作空间编码.navicate中的数据库编码.mysql中my.ini中的配置之后还是出现乱码. ...
- The multi-part request contained parameter data (excluding uploaded files) that exceeded the limit for maxPostSize set on the associated connector.
springboot 表单体积过大时报错: The multi-part request contained parameter data (excluding uploaded files) tha ...
- Springboot 上传报错： Failed to parse multipart servlet request; nested exception is java.lang.IllegalStateException: The multi-part request contained parameter data (excluding uploaded files) that exceede
Failed to parse multipart servlet request; nested exception is java.lang.IllegalStateException: The ...
- MYSQL常见安装错误集:[ERROR] --initialize specified but the data directory has files in it. Abort
1.[ERROR] --initialize specified but the data directory has files in it. Abort [错误] -初始化指定,但数据目录中有文件 ...
- 启动MySQL5.7时报错:initialize specified but the data directory has files in it. Aborting.
启动MySQL5.7时报错:initialize specified but the data directory has files in it. Aborting 解决方法: vim /etc/m ...
- Data caching per request in Owin application
Data caching per request in Owin application 解答1 Finally I found OwinRequestScopeContext. Very simpl ...
- Fast data loading from files to R
Recently we were building a Shiny App in which we had to load data from a very large dataframe. It w ...
随机推荐
- Soft skill
不要害怕让别人看到自己的无知 作为高级程序员的一个好处是,当别人问一些我不懂的问题时,我可以很淡然地告诉他们: 这个东西我也不懂,因为以前没有遇到过,不过我可以看一下,然后再告诉你. 当我还是一个初级 ...
- BZOJ3798: 特殊的质数(分段打表)
题意 题目链接 Sol 分块打表,非常好的思想. 对于这种求$[A, B]$区间内xxx的数的个数,然后$B$又不算是特别大的题,考虑分段打表 每个块的大小为$10^5$,打$3 * 10^3$个.然 ...
- JAXB介绍一
参考博客: https://www.cnblogs.com/chenbenbuyi/p/8283657.html https://www.cnblogs.com/cnsdhzzl/p/8390514. ...
- iOS 当使用FD_FullscreenPopViewController的时候遇到scrollView右滑手势无法使用的解决
当我们在ViewController中有scrollView的时候, 可能会遇到右滑无法响应返回手势, 有以下解决办法: 自定义scrollView, 实现该scrollView的以下方法即可: @i ...
- Android商城开发系列（十三）—— 首页热卖商品布局实现
热卖商品布局效果如下图: 这个布局跟我们上节做的推荐是一样的,也是用LinearLayout和GridView去实现的,新建一个hot_item.xml,代码如下所示: <?xml versio ...
- jQuery_2_常规选择器-进阶选择器
进阶选择器: 1. 群组选择器 $("span,em,#box") 获取多个选择器的DOM对象 <div id="d1">div< ...
- codevs 2620 战壕
时间限制: 1 s 空间限制: 32000 KB 题目等级 : 黄金 Gold 题目描述 Description Smart和Sarah正在玩一个即时战略游戏. Smart在他的基地附近建立了n个 ...
- m3u8视频下载方法
部分网站的视频内容,采用了m3u8的格式.正常打开网页可以,但是如果想下载到本地,就存在一定问题了.这里可以再获取到m3u8地址之后,利用vlc软件,来下载m3u8的视频. 工具:Firefox浏览器 ...
- IOS Block动画
● + (void)transitionFromView:(UIView *)fromView toView:(UIView *)toView duration:(NSTimeInterval)dur ...
- 【HDU4507】恨7不成妻（数位DP）
点此看题面 大致题意: 让你求出一段区间内与\(7\)无关的数的平方和.与\(7\)无关的数指整数中任意一位不为\(7\).整数的每一位加起来的和不是\(7\)的整数倍.这个整数不是\(7\)的倍数. ...