Has anyone tried a multi-domain/multi-database/single-deployment Rails setup?

Question

I'm developing an app (basically an intranet) which has a few small sets of users, each a company using the app internally.

Up to now, each set of users has its own deployment with a separate domain name and database, but all living on the same server. This means that each time I have to push an upgrade I need to deploy once per client. Also, each new client means adding a new deploy target, for which I'm currently using Capistrano's multistage plugin, but it's getting a bit ridiculous.

This is a less than ideal setup, so after some thought I came up with the idea of modifying the app so that it handles multiple domains, each mapped to a different database, but on a single deployment. I created a small proof-of-concept app which basically has a before_filter in ApplicationController acting as a multiplexer for domains/databases, connecting ActiveRecord to each domain's database on each request. This worked really well, but I haven't applied this to the big app yet and I can think of at least one problem down the road: running migrations across all databases. I'm pretty sure I can work around that one though, maybe I'll tweak the rake task a little, but I'm worried that might not be the last of problems with it.

Has anyone ever tried this, or can think of any major reasons why this would be a bad idea? I would like to listen to some opinions.

Thanks!

Answer 1

This is usually called multi-tenancy. Here is a presentation or video about doing it in rails. Couldn't tell if it was any good, it was blocked here at work.

And no, there is nothing wrong with it as an idea. I'm not sure about your particular implementation, but I have worked on apps that were multi-tenant in the past and can't say we ever had much difficulty except when trouble clients wanted to stay on a legacy version of the product and we wanted to move forward.