~loggerhead-team/loggerhead/trunk-rich

"TurboGears support for Zope Page Templates"

import StringIO

import logging

import os

import pkg_resources

from simpletal import simpleTAL, simpleTALES

log = logging.getLogger("turbogears.zptsupport")

_zpt_cache = {}

def zpt(tfile):

    tinstance = _zpt_cache.get(tfile)

    stat = os.stat(tfile)

    if tinstance is None or tinstance.stat != stat:

        tinstance = _zpt_cache[tfile] = TemplateWrapper(

            simpleTAL.compileXMLTemplate(open(tfile)), tfile, stat)

    return tinstance

class TemplateWrapper(object):

    def __init__(self, template, filename, stat):

        self.template = template

        self.filename = filename

        self.stat = stat

    def expand(self, **info):

        context = simpleTALES.Context(allowPythonPath=1)

        for k, v in info.iteritems():

            context.addGlobal(k, v)

        s = StringIO.StringIO()

        self.template.expandInline(context, s)

        return s.getvalue()

    def expand_(self, f, **info):

        context = simpleTALES.Context(allowPythonPath=1)

        for k, v in info.iteritems():

            context.addGlobal(k, v)

        self.template.expand(context, f, 'utf-8')

    @property

    def macros(self):

        return self.template.macros

class TurboZpt(object):

    extension = "pt"

    def __init__(self, extra_vars_func=None):

        self.get_extra_vars = extra_vars_func

    def load_template(self, classname, loadingSite=False):

        """Searches for a template along the Python path.

        Template files must end in ".pt" and be in legitimate packages.

        Templates are automatically checked for changes and reloaded as

        neccessary.

        """

        divider = classname.rfind(".")

        if divider > -1:

            package = classname[0:divider]

            basename = classname[divider+1:]

        else:

            raise ValueError, "All templates must be in a package"

        tfile = pkg_resources.resource_filename(

            package, "%s.%s" % (basename, self.extension))

        return zpt(tfile)