Angelo discusses the Zend PHP 5 Certification Study Guide 2nd edition and explains how to implement Open Flash Charts into your PHP project.
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If you’re looking for clean and simple resource or reference on the Rewrite Module in Apache, look no further. This page is the most useful and to the point resource on the subject I have come across to date.
Module Rewrite - URL Rewriting Guide
If you are looking for a cheat sheet, check out I Love Jack Daniels’ mod_rewrite Cheat Sheet for a Rewrite Module cheat sheet as well as others.
Lighttpd web server, also known as Lighty, is an excellent web server and has potential to replace Apache completely. I am slowly migrating web sites that use feature specific settings in Apache to use Lighty. A few months ago I ran into a problem with Lighty’s ModRewrite alternative for rewriting URLs. Lighty uses two separate modules to handle internal rewrites and Location: redirects. It uses the common HTTP 301 Moved Permanently status code. For most circumstances, this works well but in some cases the application may require that the redirect only be temporary and return the HTTP 302 Found status code. Instead of modifying the mod_redirect.c source and changing the http_status code value from 302 to 301, I added new code to support a new url.redirect parameter url.redirect-found.
I’ve posted the source to the Lighttpd bug tracking system in hopes it will be added to a future version of Lighty. http://trac.lighttpd.net/trac/ticket/1446
This addition should help the Lighty web server to be capable of handling the appropriate HTTP status codes for all situations that may arise for the web site in question.
Three months ago I started looking at an alternative web server to serve URL redirects. The need arose when I found that Apache web server would consume a lot of system memory when testing simulated spikes to the server. Apache could handle between 1,200 to 1,700 requests a second. Though the number of requests per second was satisfactory, the memory usage when these simulated spikes was concerning.
I did some research and came across Lighttpd web server, also known as Lighty. Lighty took some time to figure out, but once I did I found the XML style configuration files were not hard to implement and understand. I did find the rewriting to be rather limited in comparison to the mod_rewrite module found in Apache. Never the less, I was able to duplicate the rewrite that I had in Apache in Lighty. For my application, I did have to modify the Lighty source code that way redirects returned a 302 HTTP response (It defaulted to 301 without any way of changing in the configuration files).
After performing similar tests with the same server configured with Lighty, I found that Lighty could handle between 3,900-4,100 requests per second. On top of this, memory usage was minimized to only a fraction of the total memory available on the server. Processor usage did increase, but was not substantial enough to warrant the change.
I am currently experimenting with combining Lighty with Apache services on one server in order to utilize the best of both worlds. See my post on the lighttpd.net forums: http://forum.lighttpd.net/topic/13830
Lighty may be able to also serve dynamic PHP files using FastCGI faster than Apache. I am still concerned that PHP will not function correctly since it is not multi-threaded friendly. I also have security concerns based on what I’ve seem with source code being exposed with a popular web site recently, I am not ready to take on that much risk.
If your web server to supports .htaccess files and you can specify “Options” from within your .htaccess file, then the following is a quick 1 line solution to your file listing needs.
So you just uploaded a tun of pictures to a web directory and you want a list of all the images. Since the only types of files in the directory are images, the security risk of displaying the list diminishes. In actuality, the list of images can be quite useful especially when trying to find a specific one.
The answer, create a 1 line .htaccess file with the following: Options Indexes
If you don’t have control over your apache configuration files and this option is not available to you, don’t fret. Chris Snyder created an excellent php script that allows you to list the contents of a web directory.
Link: http://chxo.com/scripts/image-list.php
This script is very useful, I’ve customized it for my subversion repository in order to display a list of repositories in the root of the subversion web server.
I’ve been auditing apache web logs from statistics gathered in AWStats. I found 6 different IP addresses that are using a lot of the servers bandwidth. After looking at the logs, I discovered one of the IP addresses was a spammer and the rest are from web robots or bots. One bot used over 2.5GB of traffic last month. That is unbelievable. That is 2.5% of the months bandwidth. Of course Google and Yahoo combined have downloaded almost 30GB, but we want Google and Yahoo to index our sites. So what can we do to save our bandwidth and still provide the information to the search engines? Compress it with Mod_deflate!
The mod_deflate module in Apache is not new. What is new is the trend to use it. The deflate module uses gzip compression and is relatively fast in comparison to the bandwidth time. You can do the math, but if your page was 1MB and took 20 seconds to download, and compressed it is 250k and takes 1 second to compress, 5 second to download, and 2 second to decompress, the compression method is faster. You can crunch numbers till you are blue in the face, but the basic premise holds true.
First, you need to make sure the mod_deflate module is enabled in apache. Look for the line in your apache configuration files and uncomment:
LoadModule deflate_module modules/mod_deflate.so
Then add the following lines within a <Location> or <VirtualHost> section.
SetInputFilter DEFLATE
The above will compress everything. Instead of compressing everything, especially if you have a lot of files on your web site such as images, media, zip files, etc.. that are already compressed, you may want to only add compression for particular content types. To compress specific content types, replace the SetInputFilter with one or more of the following.
AddOutputFilterByType DEFLATE text/html
AddOutputFilterByType DEFLATE text/plain
AddOutputFilterByType DEFLATE text/xml
AddOutputFilterByType DEFLATE text/css
AddOutputFilterByType DEFLATE text/javascript
AddOutputFilterByType DEFLATE application/x-javascript
AddOutputFilterByType DEFLATE application/xml
AddOutputFilterByType DEFLATE application/x-httpd-php
If you work with other content types such as application/xml, you can add those as well.
You can test your server by using the GID Network gzip test located here: http://www.gidnetwork.com/tools/gzip-test.php
Now that your web server is using compression, you can focus on other things like programming or eating pizza.
Have you ever made a lot of changes to your apache conf files on your web server that you were worried that the changes may result in apache not restarting? I know I have. There is a way to check your changes before you restart the running service.
cmd:
httpd -t # or /usr/sbin/httpd -t
If everything was entered correctly, you should see the following message printed: “Syntax OK”.
If there are errors, it will print the first one it finds and exits. Otherwise it will print all the warnings if any and then print the “Syntax OK” message.
If you keep each virtual host in a separate configuration files like I do, then you can check the specific httpd.conf file.
cmd:
httpd -t -f /path/to/virtual/httpd.conf
