


我所经历的大文件数据导出(后台执行,自动生成),数据导出自动生成
一、前言
记录一下以前做的后台excel格式导出统计信息的功能,也是最近同事问到了相关东西,一时之间竟忘了具体的细节,因此记录一下;
大家知道,excel导出数据的功能,后台几乎是必须功能,一般都是点击后,生成文件然后自动下载,
如果是数据量小的话,一下子便可请求完成,从而下载到本地;
但是,如果数据量特别大的时候,页面就必须一直在等待,直到写入excel成功,
这样便影响了后台使用者无法操作其他页面,为此,对excel导出做了以下功能优化:
二、生成excel文件
生成excel文件的方法有很多,暂不一一记录,只是记录本次的方法;
这里用到了table的html格式,以及相应的excel的声明
(隐约记得其他的方法用office07打开的时候好像是乱码,后面尝试用csv格式文件,可还是乱码,所以用了table的形式)
文件的开头:

当然,文件中间就是一些tr td 标签了。
三、让程序在后台执行
<p><span> 场景:</span></p> <p><span> 用户点击 生成excel后,跳转到下载页面,程序在后台执行,用户可不必等待生成完成,可执行其他操作;</span></p> <p><span> 下载页面可看到文件生成的进度以及是否可下载状态</span></p> <p><span> 思路:</span></p> <p><span> 点击 生成excel,显示下载页面 ---> show_download方法</span></p> <p><span> 生成excel ---> create_excel 方法</span></p>
show_download方法中调用 create_excel方法,而show_download 方法中,自己用了一下命令行执行程序的方式,
利用php命令行的方式,把参数传递给 create_excel方法
<span><span>1</span> <span>//</span><span> $cmd = "/usr/bin/php /home/xxx/xxx.php " . $strjoin . " >/dev/null & "; </span><span>2</span> <span> // $a=exec($cmd, $out, $returndata);</span> <span>3</span> <span>4</span> <span>5</span> <span>$command</span> = "/usr/bin/php ".STATISTIC_EXPORT_SCRIPT_DIR."xxx.php " . "'" .<span>$strjoin</span> ."'". " " . <span>$uid</span> . " ". <span>$action</span> ." & "<span>; </span><span>6</span> <span>$process</span> = <span>proc_open</span>(<span>$command</span>, <span>array</span>(),<span>$pipes</span><span>); </span><span>7</span> <span>$var</span> = <span>proc_get_status</span>(<span>$process</span><span>); </span><span>8</span> <span>proc_close</span>(<span>$process</span><span>); </span><span>9</span> <span>$pid</span> = <span>intval</span>(<span>$var</span>['pid'])+1;</span>
而在create_excel方法中:
需填写以下代码:
<span><span>1</span> <span>set_time_limit</span>(0); <span>//</span><span>取消脚本运行时间的超时上限</span> <span>2</span> <span>3</span> <span>ignore_user_abort</span>(<span>TRUE</span>); <span>//</span><span>后台运行,不受用户关闭浏览器的影响</span></span>
调用相关的api得到数据:
<span><span>1</span> <span>$statistic</span> = <span>call_user_func</span>(<span>array</span>('shellscript','get_result'),<span>$url</span>,<span>$params</span><span>); </span><span>2</span> <span>if</span>(!<span>is_object</span>(<span>$statistic</span>) || !<span>isset</span>(<span>$statistic</span>->data-><span>items)){ </span><span>3</span> <span>usleep</span>(400000);<span>//</span><span>停止400毫秒</span> <span>4</span> <span>$statistic</span> = <span>call_user_func</span>(<span>array</span>('shellscript','get_result'),<span>$url</span>,<span>$params</span><span>); </span><span>5</span> }</span>
四、显示文件生成进度
但是怎么显示相应的文件生成进度呢,怎么知道文件到底生成好了没有呢?
这里,我用到的方法是,在写入数据文件的时候data.xsl,每个数据文件都生成一个对应的文件进度文件,暂且称为flag_data.xsl;
思路:
查看文件的进度方法:

五、下载文件
文件的下载就好说了,既然已经都生成成功,下载的方法如下:
<span><span> 1</span> <span>public</span> <span>function</span><span> execscript_download(){ </span><span> 2</span> <span>$filename</span> = <span>$_REQUEST</span>['filename'<span>]; </span><span> 3</span> <span>$uid</span> = <span>$_REQUEST</span>['uid'<span>]; </span><span> 4</span> <span>$file_dir</span> = STATISTIC_EXPORT_FILE_DIR.<span>$uid</span>.'/'.<span>$filename</span><span>; </span><span> 5</span> <span>if</span> (!<span>file_exists</span>(<span>$file_dir</span><span>)){ </span><span> 6</span> <span>header</span>("Content-type: text/html; charset=utf-8"<span>); </span><span> 7</span> <span>echo</span> "File not found!"<span>; </span><span> 8</span> <span>exit</span><span>; </span><span> 9</span> } <span>else</span><span> { </span><span>10</span> <span>ini_set</span>("memory_limit","500M"<span>); </span><span>11</span> <span>header</span>('Content-Description: File Transfer'<span>); </span><span>12</span> <span>header</span>('Content-Type: application/octet-stream'<span>); </span><span>13</span> <span>header</span>('Content-Disposition: attachment; filename='.<span>basename</span>(<span>$file_dir</span><span>)); </span><span>14</span> <span>header</span>('Content-Transfer-Encoding: binary'<span>); </span><span>15</span> <span>header</span>('Expires: ' . <span>gmdate</span>('D, d M Y H:i:s') . ' GMT'<span>); </span><span>16</span> <span>header</span>('Cache-Control: must-revalidate,post-check=0, pre-check=0'<span>); </span><span>17</span> <span>header</span>('Pragma: public'<span>); </span><span>18</span> <span>header</span>('Content-Length: ' . <span>filesize</span>(<span>$file_dir</span><span>)); </span><span>19</span> <span>readfile</span>(<span>$file_dir</span><span>); </span><span>20</span> <span> } </span><span>21</span> <span>22</span> }</span>
六、上线后出现的问题
本地本来已经测试完毕,可上线后,却出现了奇怪的问题;
<p><span> 现象描述:</span></p> <p><span> 当在后台点击生成文件,跳转到下载页的时候,因为下载页是显示文件进度的页面,</span><br /><span> 竟然出现有时候有刚刚点击的文件进度,有时候没有,就感觉没有生成相应的文件一样;</span></p> <p><span> 解决方法:</span></p> <p><span> 因为数据文件和进度文件都是生成在程序的某个文件夹file中,所以读取的时候都是读取的文件夹下的文件,从而判断显示进度;</span></p> <p><span> 后面才知道,由于后台程序有两台服务器,导致读取以及下载的时候找不到相应的文件夹,两个服务器相应的文件夹弄个共享目录就可以了</span></p>
七、相应的后续优化
由于下载的文件多了,导致文件夹下的文件越来越多,而原来生成的文件是没有价值的,所以加了个定期删除文件的功能,只保留近七天的文件
当然可以用crontab,只不过我比较懒,是在点击生成文件的时候,判断了一下文件夹中的过期文件,从而删除
<span><span> 1</span> <span>public</span> <span>function</span><span> execscript_process_show(){ </span><span> 2</span> <span>$this</span>->load->library('smarty'<span>); </span><span> 3</span> <span>$uid</span> = <span>$_REQUEST</span>['uid'<span>]; </span><span> 4</span> <span>$url_dir</span> = STATISTIC_EXPORT_FILE_DIR.<span>$uid</span> .'/';<span>//</span><span>@todo</span> <span> 5</span> <span>if</span>(!<span>is_dir</span>(<span>$url_dir</span><span>)){ </span><span> 6</span> @<span>mkdir</span>(<span>$url_dir</span>,0777<span>); </span><span> 7</span> <span> } </span><span> 8</span> <span>$files</span> = <span>scandir</span>(<span>$url_dir</span><span>); </span><span> 9</span> <span>if</span>(!<span>empty</span>(<span>$files</span><span>)){ </span><span>10</span> <span>foreach</span> (<span>$files</span> <span>as</span> <span>$key</span> => <span>$value</span><span>) { </span><span>11</span> <span>if</span>(<span>$value</span>!='.' && <span>$value</span>!='..'<span>){ </span><span>12</span> <span>foreach</span> (<span>$files</span> <span>as</span> <span>$key</span> => <span>$value</span><span>) { </span><span>13</span> <span>if</span>(<span>$value</span>!='.' && <span>$value</span>!='..'<span>){ </span><span>14</span> <span>if</span>(<span>substr</span>(<span>$value</span>, 0 , 5)!="flag_"<span>){ </span><span>15</span> <span>$filenamedate</span> = <span>substr</span>(<span>$value</span>, 0,10<span>); </span><span>16</span> <span>$today</span> = <span>date</span>('Y-m-d',<span>time</span><span>()); </span><span>17</span> <span>$filenamedate</span> = <span>date</span>('Y-m-d',<span>strtotime</span>(<span>$filenamedate</span>)+(STATISTIC_FILE_EXPIRE_DAY-1)*24*3600<span>); </span><span>18</span> <span>if</span>(<span>$today</span>><span>$filenamedate</span>){<span>//</span><span>文件过期</span> <span>19</span> @<span>unlink</span>(<span>$url_dir</span> . <span>$value</span><span>); </span><span>20</span> @<span>unlink</span>(<span>$url_dir</span> . 'flag_' . <span>$value</span><span>); </span><span>21</span> <span> } </span><span>22</span> <span> } </span><span>23</span> <span> } </span><span>24</span> <span> } </span><span>25</span> <span> } </span><span>26</span> <span> } </span><span>27</span> <span> } </span><span>28</span> <span>29</span> <span>$this</span>->smarty->assign('uid',<span>$uid</span><span>); </span><span>30</span> <span>$this</span>->smarty->display('interact/statistic/execscript.tpl'<span>); </span><span>31</span> }</span>
八、后记
大文件的导出大体就是这个样子,欢迎大家吐槽,共同交流;
当时在用命令行执行方法的时候,也参考了一下相应的资料,记录一下;
<span>http://blog.csdn.net/yysdsyl/article/details/4636457 http://www.codesky.net/article/201202/163385.html http://www.cnblogs.com/zdz8207/p/3765567.html http://blog.163.com/mojian20040228@126/blog/static/4112219320097300922992/ http://php.net/manual/en/features.commandline.php http://blog.csdn.net/yangjun07167/article/details/5603425 http://blog.csdn.net/yunsongice/article/details/5445448 http://www.cppblog.com/amazon/archive/2011/12/01/161281.aspx http://blog.51yip.com/tag/proc_open http://www.justwinit.cn/post/1418/ http://limboy.me/tech/2010/12/05/php-async.html</span>

PHP is used to build dynamic websites, and its core functions include: 1. Generate dynamic content and generate web pages in real time by connecting with the database; 2. Process user interaction and form submissions, verify inputs and respond to operations; 3. Manage sessions and user authentication to provide a personalized experience; 4. Optimize performance and follow best practices to improve website efficiency and security.

PHP uses MySQLi and PDO extensions to interact in database operations and server-side logic processing, and processes server-side logic through functions such as session management. 1) Use MySQLi or PDO to connect to the database and execute SQL queries. 2) Handle HTTP requests and user status through session management and other functions. 3) Use transactions to ensure the atomicity of database operations. 4) Prevent SQL injection, use exception handling and closing connections for debugging. 5) Optimize performance through indexing and cache, write highly readable code and perform error handling.

Using preprocessing statements and PDO in PHP can effectively prevent SQL injection attacks. 1) Use PDO to connect to the database and set the error mode. 2) Create preprocessing statements through the prepare method and pass data using placeholders and execute methods. 3) Process query results and ensure the security and performance of the code.

PHP and Python have their own advantages and disadvantages, and the choice depends on project needs and personal preferences. 1.PHP is suitable for rapid development and maintenance of large-scale web applications. 2. Python dominates the field of data science and machine learning.

PHP is widely used in e-commerce, content management systems and API development. 1) E-commerce: used for shopping cart function and payment processing. 2) Content management system: used for dynamic content generation and user management. 3) API development: used for RESTful API development and API security. Through performance optimization and best practices, the efficiency and maintainability of PHP applications are improved.

PHP makes it easy to create interactive web content. 1) Dynamically generate content by embedding HTML and display it in real time based on user input or database data. 2) Process form submission and generate dynamic output to ensure that htmlspecialchars is used to prevent XSS. 3) Use MySQL to create a user registration system, and use password_hash and preprocessing statements to enhance security. Mastering these techniques will improve the efficiency of web development.

PHP and Python each have their own advantages, and choose according to project requirements. 1.PHP is suitable for web development, especially for rapid development and maintenance of websites. 2. Python is suitable for data science, machine learning and artificial intelligence, with concise syntax and suitable for beginners.

PHP is still dynamic and still occupies an important position in the field of modern programming. 1) PHP's simplicity and powerful community support make it widely used in web development; 2) Its flexibility and stability make it outstanding in handling web forms, database operations and file processing; 3) PHP is constantly evolving and optimizing, suitable for beginners and experienced developers.


Hot AI Tools

Undresser.AI Undress
AI-powered app for creating realistic nude photos

AI Clothes Remover
Online AI tool for removing clothes from photos.

Undress AI Tool
Undress images for free

Clothoff.io
AI clothes remover

AI Hentai Generator
Generate AI Hentai for free.

Hot Article

Hot Tools

SublimeText3 Chinese version
Chinese version, very easy to use

SAP NetWeaver Server Adapter for Eclipse
Integrate Eclipse with SAP NetWeaver application server.

Dreamweaver Mac version
Visual web development tools

Safe Exam Browser
Safe Exam Browser is a secure browser environment for taking online exams securely. This software turns any computer into a secure workstation. It controls access to any utility and prevents students from using unauthorized resources.

MinGW - Minimalist GNU for Windows
This project is in the process of being migrated to osdn.net/projects/mingw, you can continue to follow us there. MinGW: A native Windows port of the GNU Compiler Collection (GCC), freely distributable import libraries and header files for building native Windows applications; includes extensions to the MSVC runtime to support C99 functionality. All MinGW software can run on 64-bit Windows platforms.