[Buildbot-devel] waterfall/jinja - where do variables like 'categories' come from?

[Stephen Davis]

Noob questions regarding the waterfall template.  I am in the crowd of folks who misses the "order of builders = order they were added to config" waterfall display but I would be totally fine with it if I could use builder categories to group them together like the console page does.  I'm looking at the default templates, waterfall.html & console.html, and the former references a variable called "builders" to create the table columns and the latter uses "categories" and "slaves[c.name]" to create the columns.

a) Where do these variables come from?  I've looked briefly at the jinja documentation but it's not obvious (yet).

b) What is the relationship between the builders and slaves variables as far as determining when I should decide to use one or the other?  Put another way, if I used the console.html mechanism of looping through the categories, could I use "builders[c.name]" instead?

thanks,
stephen