Source code for chaste_codegen._load_template

#
# Methods to configure jinja2 and load templates.
#
import logging
import os
import posixpath

import jinja2

import chaste_codegen as cg


# Shared Jinja environment
_environment = None


def _jinja_environment():
    """
    Returns a shared Jinja environment to create templates from.
    """
    global _environment
    if _environment is None:
        _environment = jinja2.Environment(
            # Automatic loading of templates stored in the module
            # This also enables template inheritance
            loader=jinja2.PackageLoader('chaste_codegen', cg.TEMPLATE_SUBDIR),

            # Keep a single trailing newline, if present
            keep_trailing_newline=True,

            # Don't replace undefined template variables by an empty string
            # but raise a jinja2.UndefinedError instead.
            undefined=jinja2.StrictUndefined,
        )
    return _environment


def load_template(*name):
    """
    Loads a template from the local template directory.

    Templates can be specified as a single filename, e.g.
    ``load_template('temp.txt')``, or loaded from subdirectories using e.g.
    ``load_template('subdir_1', 'subdir_2', 'file.txt')``.

    """
    # Due to a Jinja2 convention, posixpaths must be used, regardless of the
    # user's operating system!
    path = posixpath.join(*name)
    if os.path.sep != '/' and os.path.sep in path:  # pragma: no linux cover
        log = logging.getLogger()
        log.warning('Paths to templates must be specified as posix paths.')

    env = _jinja_environment()
    return env.get_template(path)