mr.scripty 1.0b1 on PyPI

Mr.Scripty

A quick way to build recipes by using python directly inside zc.buildout

Contents

Mr.Scripty
Supported options
- Functions vs Constants
- Init, Install and Update
Bugs and Repo
Examples

The recipe supports any number of options, which are Python functions. Since the ini parser used with buildout doesn't preserve initial whitespace each line of your method should start with a ... followed by the whitespace as per normal python. They will look like this:

[myscripts]
recipe = mr.scripty
MAX = 10
function1 =
  ... x = range(1,int(self.MAX))
  ... return ' '.join(x)

[myrecipe]
recipe = something.recipe
argument = ${myscripts:function1}

The return value will be stored as a value in the buildout parts options which is available for replacement in other buildout parts. What is returned is always converted to a string.

Functions vs Constants

Options all in upper case are treated as string constants and added to the Recipe instance as an attribute. All other options will be treated as python functions.

As each option is a Python function or variable, it needs to possess an acceptable function identifier (see http://docs.python.org/reference/lexical_analysis.html#grammar-token-identifier). For instance, typical buildout options with hyphens (such as environment-vars) will be invalid.

Since these functions are actually methods self is an available local variable which refers to the recipe instance. self.options, self.buildout and self.name are available.

Any option beginning with _ is not evaluated so can be used as a private function.

Init, Install and Update

There are three special functions which are evaluated regardless if they are called from another recipe and whose value isn't stored.

init: Init is called everytime the recipe is loaded. This function allows you to reduce the need for multiple functions that may do similar jobs, remove the need for a dummy option in order to execute arbitrary code (and other uses), like so:

[myscripts]
recipe = mr.scripty
init =
    ... import math
    ... self.options['pi'] = str(math.pi)
    ... self.options['e'] = str(math.e)
    ... self.options['sqrt_two'] = str(math.sqrt(2))

After running buildout, the options pi, e, and sqrt_two will all be available for use against the myscripts section like so: ${myscripts:sqrt_two}. See the example regarding `Offsetting port numbers`_ for more information.

install is called if the arguments (functions or constants) have changed since the last run or if it's never run before.

update is called each time (but after init)

These can be used as quick in-place replacement for creating a real recipe and have the same semantics as detailed in http://www.buildout.org/en/latest/docs/tutorial.html?highlight=update#writing-recipes.