Building a 'multi-site' application

Question

I'm planning an application that allow users to create a specific type of website. I wanted to link account names to 'account.myapp.com'. Going to 'account.myapp.com' will serve up a website. I haven't a clue on how to map this. I'll be using Code Igniter as my development tool.

I would like to give users the ability to add a registered domain name for their website, rather than use the standard sub domain. Any tips/methods on this?

Also, what are some pitfalls and problems I should be looking for when developing something with this design? My biggest concern is backing myself in a corner with bad database design, and creating a nightmare of an app to maintain or update.

Thanks for your time!

Answer 1

First, you have to setup your Apache (or whatever webserver you're using) to give every subdomain the same DNS settings (wildcard match). Then, you have to use CodeIgniter's routing features to parse the subdomain from the request URL, set that as param (or whatever that's called in CodeIgniter) and have some fun with it in your controller.

About pitfalls and problems: that depends on what you want to do. ;)

Answer 2

Your plan for having a single app that serves all the sites is going to be quite an undertaking and a lot of work. That is not to say it isn't possible (plenty of enterprise CMS's, including Sharepoint, allow you to run 'virtual sites' etc. from a single install).

You are going to need to undertake a lot of planning and design, specifically on the security front, to make sure the individual sites operate in isolation. I assume that each site will have its own account(s) - you are going to have to do a lot of work to make sure users can't accidentally (or malicously) start editing another site.

And you are right to consider maintanence - if you have all the sites running under a single application, and therefore a single database, that database is going to get big and messy, very quickly. It also then becomes a single point of failure.

A better plan would be to develop a self-contained solution (for a single website) - this can then run from it's own directory, with it's own database with it's own set of accounts. It would be significantly smaller (in terms of both code and database) and therefore probably perform a lot better. Day-to-Day maintanence would be easier (restore a website from backup), but software updates (to add a new feature) would be a bit trickier, though as it's PHP it's just file uploads and SQL patches, therefore you can automate this with ease.

In terms of domains: if you went with the invidual app (one per website) approach, you can use Apache's Dynamic Virtual Hosts feature, which effectively maps a URL to the filesystem, (so website.mydomain.com could be translated to automatically be severed from /home/vhosts/com/mydomain/website): thus deploying a new website would be a matter of simply copying the files into the correct directory, creating the database, and updating a config file, all of which could be automated with ease.

If users want to use their own URL's then they have to firstly update their DNS to point to your server and secondly you would need to configure an Apache vhost for that domain, which would probably involve a restart of apache and thus affect all other users.

Answer 3

This is very easy to do in codeigniter and can be complete done using routes.php, and a pre-controller hook.

THAT BEING SAID... Don't do this. It's generally not a good idea. Even 37Signals, who made this sort of account management famous is recanting, and moving towards centralized accounts. Check http://37signals.com/accounts

Answer 4

If I'm understanding your question correctly, you need to setup wildcard DNS, and use Apache mod_rewrite to internally redirect (example) myaccount.myapp.com to myapp.com/?account=myaccount. You app logic can take it from there.

I just Googled, "wildcard dns mod_rewrite account" (without quotes) and found some examples with instructions, such as:

http://www.reconn.us/content/view/46/67/

This is a valid and desirable way to structure certain web apps IMO. I'm not aware of serious drawbacks.

I don't really know of a great (automated/scalable) way to allow the users to specify their own individual domain names but you might be able to do it if you had them modify their domain's DNS to point to your web server, then added a ServerAlias directive to your "myapp" Apache configuration. You're still left with the problem of your myapp runtime instance understanding that requests coming through a customer's domain are specific to a customer account. So (example) customeraccount.com really equates to myapp.com/?account=customeraccount. Some more mod_rewrite rules could probably take care of this, but it's not automated (perhaps it could be though with an include file or such).

Sorry, you said you were using CodeIgniter ... substitute in then myapp.com/account/myaccount where I wrote myapp.com/?account=myaccount.