John Topley’s Weblog

I’m pleased to report that my AssetsGraphed Ruby on Rails application has been running continuously for over two hundred days now, as the screenshot below taken from my installation of monit shows. Okay, so AssetsGraphed isn’t exactly getting hammered like Facebook, but this level of reliability supports my decision to choose Rails Machine for hosting my Rails applications. Their choice of running Xen-based VPSs on Linux would appear to be a wise one and I know that 37signals themselves are moving in this direction.

The next milestone will be a year’s continuous uptime—let’s hope that posting this isn’t the kiss of death that takes AssetsGraphed offline! Happy New Year everyone.

As part of my process of continuous and sometimes arduous improvement of my AssetsGraphed web application, I’ve recently added slightly better localisation support. Localisation—sometimes called L10n—in the context of software means adding special features for a specific locale. It usually follows internationalisation (i18n), which is the full-blown support of different languages and cultures.

AssetsGraphed isn’t currently internationalised, and unless there is suddenly a massive demand for it to be, I have no plans on changing this. So the user interface text will remain in English and read from left to right, as that’s what I know. I also know that proper internationalisation is a bit more involved than that! What I have changed however is how the display of currencies is handled. As you might imagine this is a fairly significant part of a financial asset tracking application.

AssetsGraphed has supported multiple currencies from day one and users can select which one they want to use on the Settings screen. The example below shows an extract from the Assets screen with the U.S. Dollar as the currency:

That’s all well and good, but it’s not always appropriate to prefix the amount with the currency symbol, and not all cultures group digits using a comma. In France for example, they use a period. ISO 31-0 mandates a space character. To accommodate all this, the digit grouping symbol is now a per-user setting and as the system administrator I can control whether the currency symbol is displayed before or after the amount. Here’s what it looks like with Swiss Francs:

I recently added Shaun Inman’s superb Mint statistics package to my AssetGraphed Rails Machine installation. As the installation wasn’t particularly straightforward, I thought I’d write this little guide for others who may be struggling. I should point out that the real credit for the information here goes to Bradley Taylor from Rails Machine who was extremely helpful and persistent.

First of all, I should point out that these instructions cover installing Mint under your /public directory i.e. yoursite.tld/mint/ rather than the subdomain installation method (mint.yoursite.tld). Also note that → indicates that the line has a break in it in the instructions, but in reality it should all be on one line. With that out of the way, here’s what you need to do:

1. Install PHP on your Rails Machine using these instructions. You should have no problems with them if you follow them exactly.
2. Log in to your Rails Machine as your deploy user then become root by using su - root and entering your root password.
3. Edit /etc/httpd/conf/httpd.conf and search for DirectoryIndex index.html. Add index.php to the end if it’s not present as shown below and save the file:
   
DirectoryIndex index.html index.php
4. Edit /etc/httpd/conf/apps/yourapp.conf and add the following immediately after the RewriteEngine On line:
   
RewriteRule ^/mint/$ /mint/index.php [QSA]
5. Now find the three lines shown below:
   
# Redirect all non-static requests to cluster
RewriteCond %{DOCUMENT_ROOT}/%{REQUEST_FILENAME} !-f
RewriteRule ^/(.*)$→
balancer://yourapp_cluster%{REQUEST_URI} [P,QSA,L]—And add the following line immediately before them:

   # Don't redirect requests to /mint
RewriteCond %{REQUEST_URI} !^/mint/(.*)$

6. The full rewrite rules should look like this:
   
RewriteEngine On
RewriteRule ^/mint/?$ /mint/index.php [QSA]# Prevent access to .svn directories
RewriteRule ^(.*/)?\.svn/ - [F,L]
ErrorDocument 403 "Access Forbidden"

   # Check for maintenance file and redirect all requests
RewriteCond %{DOCUMENT_ROOT}/system/maintenance.html -f
RewriteCond %{SCRIPT_FILENAME} !maintenance.html
RewriteRule ^.*$ /system/maintenance.html [L]

   # Rewrite index to check for static
RewriteRule ^/$ /index.html [QSA]

   # Rewrite to check for Rails cached page
RewriteRule ^([^.]+)$ $1.html [QSA]

   # Don't redirect requests to /mint
RewriteCond %{REQUEST_URI} !^/mint/(.*)$

   # Redirect all non-static requests to cluster
RewriteCond %{DOCUMENT_ROOT}/%{REQUEST_FILENAME} !-f
RewriteRule ^/(.*)$→
balancer://yourapp_cluster%{REQUEST_URI} [P,QSA,L]

7. Save the file. It’s probably read-only. If you edited it using vi then you can save it even though it’s read-only by using :wq!
8. Finally, restart Apache by using /sbin/service httpd reload and log out completely from your Rails Machine.

You can now install Mint itself by adding it to your working copy directory under /public and adding it to your Subversion repository using svn add ./public/mint. Once you’ve deployed to your Rails Machine you’ll be able to complete the Mint installation by visiting http://yoursite.tld/mint/ and following the instructions.

P.S. I have spent the past several hours wrestling with WordPress trying to get the markup in this post to validate, but I have conceded defeat!

You may recall that a while ago I mentioned The Rails Way, which is a site where Rails core team members Jamis Buck and Michael Koziarski review code submissions and illustrate Rails best practices. Well, the big news is that they’ve started reviewing my code! I submitted a subset of the code from the AssetsGraphed application and the first article about it was posted yesterday. Incidentally, in case you’re wondering what I didn’t submit, it’s the code for the Reports feature and for the hidden administration interface that I use to manage users and currencies within the system etc.

The first part of the series is about removing a lot of duplicated code around the incomings and outgoings that each asset has. I always knew that having so much identical code was totally evil, but I wasn’t quite sure how to go about removing it. As is often the way with these things, it does seem kind of obvious now! I have to admit that it’s quite nerve-wracking having my early fumblings with Ruby and Rails subjected to public scrutiny, but it’s also a great way to learn, which is why I’m doing it. I intend to implement all of the improvements featured, although some of them may be more challenging to do than meets the eye because I have the added problem of having to preserve the existing data. I don’t know how many articles are going to be in the series, but there’s certainly lots of areas that I know could be done better.

I’ve also just launched the AssetsGraphed Forums where you can post any feature requests or bug reports or just generally hang out. I’m using Josh Goebel’s and Rick Olson’s Beast forum software. Go take a look!

I’ve just finished moving AssetsGraphed over to Rails Machine. The application was originally hosted by TextDrive, on the same server as this site. I don’t have any complaints about TextDrive but it was clear that I needed something more substantial for AssetsGraphed. I have lifetime hosting with TextDrive which is fine for websites but problematic for Ruby on Rails applications, as you’re limited to 48 MB resident memory and 80 MB virtual memory. If your application exceeds those limits—which are pretty generous for a shared hosting environment—then your Ruby process gets terminated without warning and it’s goodnight to your app. This was proving to be a problem for AssetsGraphed, which is fairly memory intensive due to the image processing required for the graphs.

I did consider TextDrive’s other plans, in particular their Accelerator Hosting plans whereby you get a proportion of a Solaris box and root access. It sounded great but a bit too DIY for me. I don’t mind the odd bit of system administration but I’d rather be writing code with my developer’s hat on. Enter Rails Machine. I’d read good things about them and watched the demo movie on their site. The thing that appealed to me was that they make it really very easy to set everything up and deploy your application, leaving you free to spend your brain power on development. You use their Rails Machine RubyGem and custom Capistrano recipe and it all just works, as if by magic.

I went for a three VPS set up, as shown below. One virtual server is given over entirely to the AssetsGraphed Rails application, a second one will host the forthcoming AssetsGraphed forum and blog and the third is the MySQL database server that all the applications use. It’s a nice, tidy set up:

One of the things that I didn’t appreciate from the Rails Machine site is that the don’t provide any DNS services, so you have to bring your own. I signed up for the cheapest account from DNS Made Easy and all I had to do was go into my GoDaddy domain control panel and enter the names of the nameservers that DNS Made Easy provided me with. Then, in the DNS Made Easy control panel I set up the records for the assetsgraphed.com domain so that they pointed to the IP addresses of my Rails Machine virtual servers.

Because I went for a multiple VPS arrangement, I did have a few configuration problems where my set up deviated from the instructions on the Rails Machine site, which assumes a single VPS per app. For example, something that caught me out was that when I initially set up the Rails Machine for AssetsGraphed, the assetsgraphed.com domain was still pointing to TextDrive, so I set the domain variable in the Capistrano recipe (deploy.rb) to the non-friendly server address assigned to me by Rails Machine. When I did switch the domain over and accessed the application, all I saw was a Welcome to Rails Machine! holding page. That was fixed by setting the domain variable to assetsgraphed.com and then running:

cap setup_web
cap reload_web

—To configure Apache correctly. I should stress that I got excellent help with this and the other issues that I had by dropping in to the Rails Machine Campfire chat and talking directly to Bradley Taylor, who has always been friendly and quick to help, no matter what else he was occupied with at the time!

If you come to Rails Machine from other hosting providers like I did, then you may find it a bit bare-bones at first. As well as no DNS service, there’s no Web-based control panel. It’s all driven through Capistrano and the command line. However, don’t let that put you off because once you wrap your brain around it then it all works extremely well. What you do get for your money is a high performance Rails hosting solution, with the emphasis being on solution. All the hard work of setting up a Subversion repository, importing your code into it and deploying and running your application has been done for you. Highly recommended.

I’ve just put my first Ruby on Rails application online. It’s called AssetsGraphed. It’s a free asset tracking application that also graphs your data. I created it as a vehicle for learning Rails and also because I needed a better handle on where my money goes!

AssetsGraphed lets you create assets and give them a starting balance. An asset can be anything financial that you want to track over time. For example, that dream holiday that you’re saving up for, a bank account, a retirement fund or even your pocket money. You enter incomings or outgoings against each asset and each incoming or outgoing is assigned a category, which might be something like Deposit for an incoming or Electricity Bill for an outgoing. You have complete control over your own categories. Oh, you can select which currency you want to do all this in too. There are eight to choose from, although it’s easy for me to add more. I made it default to the U.S. Dollar because that’s the nearest we have to a global currency. Don’t be offended if it’s not your currency, just select your own on the Settings screen.

The main AssetsGraphed screen gives an overview of all your assets and you can click them to drill down into the detail. Sparkline graphs plot the trends in the incomings, outgoings and overall balance for the asset. You can view or share asset activity by subscribing to its Atom feed. Yesterday I added a Reports page that for now just contains one report. It’s a pretty useful one though as it gives a breakdown of income or expenditure by category, either for all your assets or individual ones. So you can see the movement of your money very easily.

It’s important to understand that because AssetsGraphed is a learning exercise, it’s not a bulletproof web application. That means that it might crash, although I’ve been eating my own dog food on AssetsGraphed for just over a month now and it seems pretty solid. If it does crash on you then I’ll automatically get an e-mail about it and will investigate. You might find it a bit slow too. That’s because it’s actually running on the same shared server as this blog. I’m currently weighing up various options for moving it to a much more powerful hosting environment. I might even add SSL support too.

AssetsGraphed is just the first step on my journey to learn Ruby and Rails. There are lots of bits under the covers that I know could be done in better ways. I shall keep improving it as I learn more. There’s a really great community around Rails. I’d like to thank the Rails Weenie folks for patiently answering my questions and also Khoi Vinh for inspiring me with his Boxes and Arrows colour palette and letting me re-use it on AssetsGraphed.

Now that you’ve learned about AssetsGraphed and you’ve read the disclaimers, why not give it a try and let me know what you think?