Friday, June 29, 2012

Mentoring In The Large

Dave Winer has a great aspiration for programmers to engage with long-projects that involve a teaching role.

Wednesday, June 27, 2012

Command 'n' Cursor

I've been travelling with my trusty (but ageing) eeepc netbook this last week. There's much to love about it but it's starting to feel slow in comparison with my other machine.

Increasingly when I use the netbook I try to get away with doing things in a ctrl-alt-f1 shell without logging in to the GUI at all. I'm starting to wish more software could be used in this environment so I began to look at Curses, the standard library for text-window UIs. There's a convenient Python wrapper of course. And there's another nice library in Python : Cmd, for creating a command-line driven apps. That is, not programs that literally run as small tools on the shell with command-line arguments, but programs which have their own internal "repl" style loop which you drive by typing in commands. Cmd handily hides the details from you, letting you declare a subclass of the Cmd class which simply defines handlers for specific commands. It's not a million miles away from something I ended up writing to handle the commands in SdiDesk.

For some of my projects it would be useful to combine the two modes : to have Cmd style input driving a 2D textual output using Curses. Unfortunately Cmd and Curses don't obviously play well together.  Both of them want to take over the input, with Curses thinking in terms of keystrokes while Cmd still expects full lines.

Nevertheless, after a bit of exploration, and learning about Curses's textpads and Cmd's supplementary methods, I'm starting to get the two to co-operate. As this gist shows :

It doesn't do anything yet. Just handles a "greet NAME" command that prints "hello NAME". And a "quit" command that exits the program. But it has combined Cmd inputs with Curses output.

Sunday, June 10, 2012

Show Your RSS

Dave Winer reminds us to help people find our RSS feeds, as it seems that browser-makers are increasingly trying to obscure them from us.[1].

My approach is non-standard, but hopefully conveys the message :-)

[1] Rather like Steve Jobs trying to hide the file-system, some people love to take away anything that it might actually empower you to learn about.

Iterative, Test-Driven Development

My Quora answer :
Iterative, "test driven", development.
Break your idea down into a number of simple "stories", each of which describes a single chunk of activity which goes all the way through from the beginning to the end of a user's experience with the software. Importantly a story is not a traditional "component" ... but represents a complete, working but minimal slice through the functionality.

For example, a story could be "the user goes to our site at a URL and sees a page describing our idea" or, for a drawing program, "the user can create and save a jpg file" (even though that jpg file is just a blank canvas).

Once you have some stories, order them by importance. If you could only get one story working, what would be the most valuable? If you could only get two stories, which would those be?

Start on the most important story. As any particular story shouldn't be too complicated, you can probably figure out fairly intuitively the components you need in order to make it happen. (If you can't, you're trying to fit too much into a single story.) Those components might be functions, they might be objects which have several methods (if so, ONLY worry about the methods of the object which satisfy the current story, ignore any others), they might be HTML forms or templates.

Now write AUTOMATED TESTS for the components you need for this story. Unit tests for the functions and objects. Ideally something like Selenium for the web forms.

Write code to pass the tests in a test-driven style ... ie. write test, write code to pass test, refactor your code to eliminate redundancy, write next test etc. When one story is finished, start figuring out how to do the next most important and work on that.

Somewhere down your list of stories you have your minimum viable product: that is, the minimal thing which is worth releasing to your customers in order for them to give you feedback on whether this is useful to them. That is not necessarily just one story, it might be after the first three. Or the first ten. Whatever it is, once you hit it, release your product to the customers and start getting their reaction.

From now on you are in maintenance / iterative growth mode. You'll be taking the feedback from the customer to rewrite and reorder the stories. While continuing to implement them according to your best, most up-to-date, sense of priorities. You'll want to release new development to the customer as fast as reasonably possible so you can collect the feedback on your improvements too.

Don't assume that one story has to equal one release, because you'll be tempted to inflate your individual story to contain more than it should. But try to keep releases down to as few stories as possible so they can happen frequently : which maximizes both your information, and the customer's sense of progress.