gen_from_jinja.py (1632B)
1 # -*- Mode: python; indent-tabs-mode: nil; tab-width: 40 -*- 2 # vim: set filetype=python: 3 # This Source Code Form is subject to the terms of the Mozilla Public 4 # License, v. 2.0. If a copy of the MPL was not distributed with this 5 # file, You can obtain one at http://mozilla.org/MPL/2.0/. 6 7 import os 8 9 from jinja2 import Environment, FileSystemLoader, StrictUndefined 10 11 12 def main(output_fd, input_filename, *args): 13 # FileSystemLoader requires the path to the directory containing templates, 14 # not the file name of the template itself. We hang onto the leaf name 15 # which will shortly be passed to Environment.get_template. 16 (path, leaf) = os.path.split(input_filename) 17 18 # Jinja's default value for undefined is too permissive and would allow 19 # omissions to slip into the generated output. We set undefined to 20 # StrictUndefined to force Jinja to raise an exception any time a required 21 # value is missing. 22 env = Environment( 23 loader=FileSystemLoader(path, encoding="utf-8"), 24 autoescape=True, 25 undefined=StrictUndefined, 26 ) 27 tpl = env.get_template(leaf) 28 29 context = dict() 30 31 # args should all be key=value pairs that will be added to the context. 32 # Note that all values are *strings*, so the Jinja template may need to 33 # convert them to other types during processing. 34 # (As in Python, the empty string is falsy, so simple boolean checks are possible) 35 for arg in args: 36 (k, v) = arg.split("=", 1) 37 context[k] = v 38 39 # Now run the template and send its output directly to output_fd 40 tpl.stream(context).dump(output_fd, encoding="utf-8")