I would go as far as to say that over the few months I have learned so much and am aiming to become an Apache master soon!
In the last year or two, I have also been using regular expressions (regexps) to do everything and I think it's fair to say I am a master of them. I find them to be the most useful thing you can know for using your computer on a day to day basis. I now use them to search my computer or a text editor, I have made my own programming language which uses them for matching in the compiler, and very recently to match things on my website. I recently mastered htaccess files on Apache and nginx servers. As part of this I have made my site much more SEO friendly and developed BalfBlog considerably. I have been using regexps for about five or six years, but I was not exactly using them often enough and skillfully enough. Back in my C# programming days (I haven't worked on my C# projects since 2013, but I am talking about when it was my main language in about 2008 - 2010) I used regexps in Wonderword for the search and replace features, in BlackRabbit Script it was pretty much the basis of the language and in other programs I used it for text replacement tools (also included in Wonderword, but also found in my BBCL library).
Recently I brought both of these masteries together and have done so much with my website to make it better. I improved my hotlink protection due to these regexps and, to be honest, I think I did a great job since I cut ninety lines down to three with some simple regexps.
So today I'm going to share this with you.
cPanel, by default, allows you to add URLs that will not be affected by hotlink protection. As such you enter them in (or if you add a new subdomain it adds them automatically). Except as great as this is, my URLs looked like this:
RewriteCond %{HTTP_REFERER} !^http://2010.archive.jamiebalfour.scot/.*$ [NC]
RewriteCond %{HTTP_REFERER} !^http://2010.archive.jamiebalfour.scot$ [NC]
RewriteCond %{HTTP_REFERER} !^http://2012.archive.jamiebalfour.scot/.*$ [NC]
RewriteCond %{HTTP_REFERER} !^http://2012.archive.jamiebalfour.scot$ [NC]
RewriteCond %{HTTP_REFERER} !^http://airdisplays.sites.jamiebalfour.scot/.*$ [NC]
RewriteCond %{HTTP_REFERER} !^http://airdisplays.sites.jamiebalfour.scot$ [NC]
RewriteCond %{HTTP_REFERER} !^http://alpha.archive.jamiebalfour.scot/.*$ [NC]
RewriteCond %{HTTP_REFERER} !^http://alpha.archive.jamiebalfour.scot$ [NC]
RewriteCond %{HTTP_REFERER} !^http://archive.jamiebalfour.scot/.*$ [NC]
RewriteCond %{HTTP_REFERER} !^http://archive.jamiebalfour.scot$ [NC]
RewriteCond %{HTTP_REFERER} !^http://ashes-scattered.sites.jamiebalfour.scot/.*$ [NC]
RewriteCond %{HTTP_REFERER} !^http://ashes-scattered.sites.jamiebalfour.scot$ [NC]
RewriteCond %{HTTP_REFERER} !^http://be.sites.jamiebalfour.scot/.*$ [NC]
RewriteCond %{HTTP_REFERER} !^http://be.sites.jamiebalfour.scot$ [NC]
RewriteCond %{HTTP_REFERER} !^http://castleinn.sites.jamiebalfour.scot/.*$ [NC]
RewriteCond %{HTTP_REFERER} !^http://castleinn.sites.jamiebalfour.scot$ [NC]
RewriteCond %{HTTP_REFERER} !^http://clickit.education/.*$ [NC]
RewriteCond %{HTTP_REFERER} !^http://clickit.education$ [NC]
RewriteCond %{HTTP_REFERER} !^http://developer.jamiebalfour.scot/.*$ [NC]
RewriteCond %{HTTP_REFERER} !^http://developer.jamiebalfour.scot$ [NC]
RewriteCond %{HTTP_REFERER} !^http://doodle.jamiebalfour.scot/.*$ [NC]
RewriteCond %{HTTP_REFERER} !^http://doodle.jamiebalfour.scot$ [NC]
RewriteCond %{HTTP_REFERER} !^http://doodle.projects.jamiebalfour.scot/.*$ [NC]
RewriteCond %{HTTP_REFERER} !^http://doodle.projects.jamiebalfour.scot$ [NC]
RewriteCond %{HTTP_REFERER} !^http://edustream.jamiebalfour.scot/.*$ [NC]
RewriteCond %{HTTP_REFERER} !^http://edustream.jamiebalfour.scot$ [NC]
RewriteCond %{HTTP_REFERER} !^http://flitter.projects.jamiebalfour.scot/.*$ [NC]
RewriteCond %{HTTP_REFERER} !^http://flitter.projects.jamiebalfour.scot$ [NC]
RewriteCond %{HTTP_REFERER} !^http://firestarter.projects.jamiebalfour.scot/.*$ [NC]
RewriteCond %{HTTP_REFERER} !^http://firestarter.projects.jamiebalfour.scot$ [NC]
RewriteCond %{HTTP_REFERER} !^http://jamiebalfour.co.uk/.*$ [NC]
RewriteCond %{HTTP_REFERER} !^http://jamiebalfour.co.uk$ [NC]
RewriteCond %{HTTP_REFERER} !^http://jamiebalfour.scot/.*$ [NC]
RewriteCond %{HTTP_REFERER} !^http://jamiebalfour.scot$ [NC]
RewriteCond %{HTTP_REFERER} !^http://jbtest.projects.jamiebalfour.scot/.*$ [NC]
RewriteCond %{HTTP_REFERER} !^http://jbtest.projects.jamiebalfour.scot$ [NC]
RewriteCond %{HTTP_REFERER} !^http://projects.jamiebalfour.scot/.*$ [NC]
RewriteCond %{HTTP_REFERER} !^http://projects.jamiebalfour.scot$ [NC]
RewriteCond %{HTTP_REFERER} !^http://sites.jamiebalfour.scot/.*$ [NC]
RewriteCond %{HTTP_REFERER} !^http://sites.jamiebalfour.scot$ [NC]
RewriteCond %{HTTP_REFERER} !^http://wonderword.sites.jamiebalfour.scot/.*$ [NC]
RewriteCond %{HTTP_REFERER} !^http://wonderword.sites.jamiebalfour.scot$ [NC]
RewriteCond %{HTTP_REFERER} !^http://www.2010.archive.jamiebalfour.scot/.*$ [NC]
RewriteCond %{HTTP_REFERER} !^http://www.2010.archive.jamiebalfour.scot$ [NC]
RewriteCond %{HTTP_REFERER} !^http://www.2012.archive.jamiebalfour.scot/.*$ [NC]
RewriteCond %{HTTP_REFERER} !^http://www.2012.archive.jamiebalfour.scot$ [NC]
RewriteCond %{HTTP_REFERER} !^http://www.airdisplays.sites.jamiebalfour.scot/.*$ [NC]
RewriteCond %{HTTP_REFERER} !^http://www.airdisplays.sites.jamiebalfour.scot$ [NC]
RewriteCond %{HTTP_REFERER} !^http://www.alpha.archive.jamiebalfour.scot/.*$ [NC]
RewriteCond %{HTTP_REFERER} !^http://www.alpha.archive.jamiebalfour.scot$ [NC]
RewriteCond %{HTTP_REFERER} !^http://www.archive.jamiebalfour.scot/.*$ [NC]
RewriteCond %{HTTP_REFERER} !^http://www.archive.jamiebalfour.scot$ [NC]
RewriteCond %{HTTP_REFERER} !^http://www.ashes-scattered.sites.jamiebalfour.scot/.*$ [NC]
RewriteCond %{HTTP_REFERER} !^http://www.ashes-scattered.sites.jamiebalfour.scot$ [NC]
RewriteCond %{HTTP_REFERER} !^http://www.be.sites.jamiebalfour.scot/.*$ [NC]
RewriteCond %{HTTP_REFERER} !^http://www.be.sites.jamiebalfour.scot$ [NC]
RewriteCond %{HTTP_REFERER} !^http://www.castleinn.sites.jamiebalfour.scot/.*$ [NC]
RewriteCond %{HTTP_REFERER} !^http://www.castleinn.sites.jamiebalfour.scot$ [NC]
RewriteCond %{HTTP_REFERER} !^http://www.clickit.education/.*$ [NC]
RewriteCond %{HTTP_REFERER} !^http://www.clickit.education$ [NC]
RewriteCond %{HTTP_REFERER} !^http://www.developer.jamiebalfour.scot/.*$ [NC]
RewriteCond %{HTTP_REFERER} !^http://www.developer.jamiebalfour.scot$ [NC]
RewriteCond %{HTTP_REFERER} !^http://www.doodle.jamiebalfour.scot/.*$ [NC]
RewriteCond %{HTTP_REFERER} !^http://www.doodle.jamiebalfour.scot$ [NC]
RewriteCond %{HTTP_REFERER} !^http://www.doodle.projects.jamiebalfour.scot/.*$ [NC]
RewriteCond %{HTTP_REFERER} !^http://www.doodle.projects.jamiebalfour.scot$ [NC]
RewriteCond %{HTTP_REFERER} !^http://www.edustream.jamiebalfour.scot/.*$ [NC]
RewriteCond %{HTTP_REFERER} !^http://www.edustream.jamiebalfour.scot$ [NC]
RewriteCond %{HTTP_REFERER} !^http://www.flitter.projects.jamiebalfour.scot/.*$ [NC]
RewriteCond %{HTTP_REFERER} !^http://www.flitter.projects.jamiebalfour.scot$ [NC]
RewriteCond %{HTTP_REFERER} !^http://www.firestarter.projects.jamiebalfour.scot/.*$ [NC]
RewriteCond %{HTTP_REFERER} !^http://www.firestarter.projects.jamiebalfour.scot$ [NC]
RewriteCond %{HTTP_REFERER} !^http://www.jamiebalfour.co.uk/.*$ [NC]
RewriteCond %{HTTP_REFERER} !^http://www.jamiebalfour.co.uk$ [NC]
RewriteCond %{HTTP_REFERER} !^http://www.jamiebalfour.scot/.*$ [NC]
RewriteCond %{HTTP_REFERER} !^http://www.jamiebalfour.scot$ [NC]
RewriteCond %{HTTP_REFERER} !^http://www.jbtest.projects.jamiebalfour.scot/.*$ [NC]
RewriteCond %{HTTP_REFERER} !^http://www.jbtest.projects.jamiebalfour.scot$ [NC]
RewriteCond %{HTTP_REFERER} !^http://www.projects.jamiebalfour.scot/.*$ [NC]
RewriteCond %{HTTP_REFERER} !^http://www.projects.jamiebalfour.scot$ [NC]
RewriteCond %{HTTP_REFERER} !^http://www.sites.jamiebalfour.scot/.*$ [NC]
RewriteCond %{HTTP_REFERER} !^http://www.sites.jamiebalfour.scot$ [NC]
RewriteCond %{HTTP_REFERER} !^http://www.wonderword.sites.jamiebalfour.scot/.*$ [NC]
RewriteCond %{HTTP_REFERER} !^http://www.wonderword.sites.jamiebalfour.scot$ [NC]
RewriteCond %{HTTP_REFERER} !^http://www.zenlang.net/.*$ [NC]
RewriteCond %{HTTP_REFERER} !^http://www.zenlang.net$ [NC]
RewriteCond %{HTTP_REFERER} !^http://zenlang.net/.*$ [NC]
RewriteCond %{HTTP_REFERER} !^http://zenlang.net$ [NC]
I was looking at what it generated tonight since I've been fixing a lot of htaccess directive files across my site and subdomains and my other domains. I realised that I can put these down to just three lines of code and make it easier for me to maintain in the future. So this is what I've got:
RewriteCond %{HTTP_REFERER} !^https?://(www.)?(.*.)?(.*.)?jamiebalfour.co(m|.uk)(.*) [NC]
RewriteCond %{HTTP_REFERER} !^https?://(www.)?clickit.education(.*) [NC]
RewriteCond %{HTTP_REFERER} !^https?://(www.)?zenlang.net$ [NC]
So there you have a simple solution to a big problem. Learning regexps is like learning to use a calculator, it just saves so much time!
