NOTE: I want to be able to reference the principles by #. How solid are they?
So you wanna develop a new microformat?
There must be a problem to be solved. No problem, no microformat.
Once you've found your 'problem,' ask yourself: 'is there a simpler problem here?' If so, let's solve that problem first. We want to deal with the simplest problems first and only then build up to more complex problems.
Also, ask around on the web. Chances are that someone else has encountered the same problem as you. If you still believe that you have an unsolved problem, post something to the [microformats-discuss] mailing list or any other public channel (see mf.org/discuss/) We want to involve all interested parties in the discussion.
Document Current Behavior
Document current behavior. Remember, we're paving the cowpaths- before you do that you have to find the cowpaths. Your documentation should be a collection of real world markup examples and analysis. These examples should be a respresenative collection of the diversity of markup styles used for marking up the data you're trying to put into a microformat.
This collection of examples should be public, preferably on a wiki because there's no way you can do it by yourself (no matter how many of you there are) review-formats is a good example. Before developing hReview 0.4 (in progress), the collaborators when out and documented current practices around reviews.
Its quite possible during this step that you'll find someone else who's dealt with the problem you're addressing. Do your best to dialog with others who have encountered your problem. We don't want to built walls between competeing communities- we want people to work together to develop a good solution which will cover the majority of cases.
Propose a Microformat
There are other things to try before developing a microformat. First, ask yourself these questions:
- Is there a standard element in XHTML that would work?
- Is there a compound of XHTML elements that would work?
- Ok, if the answer to the above two is 'no,' we can talk about a microformat.
First you should observe the microformats principles
After you understand the principes, ask yourself: "are there any schemas we can look at which address this problem?" For example, hCard and hCalendar were built on top of the IETF standards for vCard and iCal, respectively. The developers of those standards had already developed the schema, and it became much easier to map that schema into XHTML than to develop a new schema.
Remember, microformats should be designed for humans first and machines second. If you want to know whether a proposed microformat passes this principle, ask yourself these questions: 1. If I looked at this microformat in a browser that didn't support CSS or had CSS turned off, would it still be human readable? 2. Are this format's elements stylable with CSS?
If the proposed format doesn't pass these two things, its not likely to gain any acceptance. Remember: humans first, machines second.
After proposing a microformat, you'll likely get a lot of feedback from others' interested in microformats. The proposal needs to be iterated and adapted. Microformat developlment should be collaborative and communtiy based.
Here's an ASCII-art flow diagram:
DIAGRAM: problem statement---->research/discussion---->proposal/draft---->standard ^________________V ^___________________V ^______________V
Note that each stage involves iteration. That iteration consists of discussion and feedback and may result in major changes. Do not be afraid to make major changes and please don't get too attached to any particular solutions.