Technologies

This page lists and discusses the various technologies used (and that we plan to use) in building the  trip planner.

• All of the back end (the byCycle core library) is written in  Python
  • Address normalization, geocoding, routing
  • Single-source, shortest-paths algorithm
  • Routing matrices are simple (built-in) Python objects serialized to disk
  • Database interaction
  • Web back end (i.e., the framework the Web browser interacts with)
  • and everything else

• For the front end we use XHTML, CSS, and JavaScript
  • We try to avoid tables, but sometimes it's just so much easier to use them than floating divs (or maybe I just don't know all the tr1x)
  • JavaScript is actually pretty cool. It has been derided for years by many, but it's making big comeback these days, with the likes of  Google Maps, etc. Also, it's a lot more like Python than Java. Libraries like  jQuery, which we'll be using in the next version of the UI, make it even better.

• Data is stored in a  PostgreSQL/ PostGIS database
  • Data is a crucial component of the system; without good data, a trip planner is nearly useless and most cities don't have data that would be suitable for generating bike routes
  • We receive the data as  ESRI Shapefiles, which we convert to database format and normalize; dealing with a database is a lot easier and faster for most things, and it uses less disk space because the data is normalized (repitition is reduced or eliminated)

•  GNU/Linux
  • My development machine is running  Ubuntu; Ubuntu is excellent both for software development and personal use and there's all kinds of cool, free software available just a few clicks/keystrokes away (sudo apt-get install xyz)
  • Our production server, graciously provide by  Metro, is running Fedora Core 9

•  Subversion version control system
  • Subversion (AKA SVN) rawks
  • Everyone (even non-developers) should use version control all the time

•  rsync for fast, secure, incremental backups
  • rsync also rawks; I wish I had found it sooner
  • Instead of (S)FTP and having to remembering which files you changed, it finds the changes for you and only sends the changes

•  http://www.apache.org/Apache Web server

•  Firefox Web browser
  • All Web development is done with Firefox and then "adjusted" for other browsers (most notably that stinking pile called Internet Explorer)
  • The  Firebug extension is invaluable for Web development

•  QGIS, a most excellent user-friendly GIS viewer and editor
  • Reads and can do some editing of  Shapefiles, PostGIS databases, and other formats

• I do most of my Python programming in  Emacs  Wing IDE; KomodoEdit? is also pretty nice (not Python specific)

•  Google Maps map interface

•  MapServer as a Web Mapping Service (WMS) for creating custom maps within the Google Maps interface
  • Currently, we have implemented a hybrid bike map for the Portland area; the base map is a standard Google street or satellite map and the BikeThere network is overlayed

•  JSON
  • There is actually no XML in use in the trip planner even though we use "AJAX"
  • AJAX is more a name for a technique than the use of specific languages/technologies, or so I've heard (OTOH, I would wager that JavaScript is the majority AJAX language, and I wouldn't be surprised if JSON is more popular than XML; AJAJ isn't quite as catchy though)
  • JSON is a lightweight alternative to XML that use JavaScript object notation, which makes it a natural choice for a Web application (not that I'm an XML-hater or anything)

•  Pylons Web framework