mako/cmd.py

# mako/cmd.py
# Copyright 2006-2020 the Mako authors and contributors <see AUTHORS file>
#
# This module is part of Mako and is released under
# the MIT License: http://www.opensource.org/licenses/mit-license.php
from argparse import ArgumentParser
import io
from os.path import dirname
from os.path import isfile
import sys

from mako import exceptions
from mako.lookup import TemplateLookup
from mako.template import Template


def varsplit(var):
    if "=" not in var:
        return (var, "")
    return var.split("=", 1)


def _exit():
    sys.stderr.write(exceptions.text_error_template().render())
    sys.exit(1)


def cmdline(argv=None):

    parser = ArgumentParser()
    parser.add_argument(
        "--var",
        default=[],
        action="append",
        help="variable (can be used multiple times, use name=value)",
    )
    parser.add_argument(
        "--template-dir",
        default=[],
        action="append",
        help="Directory to use for template lookup (multiple "
        "directories may be provided). If not given then if the "
        "template is read from stdin, the value defaults to be "
        "the current directory, otherwise it defaults to be the "
        "parent directory of the file provided.",
    )
    parser.add_argument(
        "--output-encoding", default=None, help="force output encoding"
    )
    parser.add_argument(
        "--output-file",
        default=None,
        help="Write to file upon successful render instead of stdout",
    )
    parser.add_argument("input", nargs="?", default="-")

    options = parser.parse_args(argv)

    output_encoding = options.output_encoding
    output_file = options.output_file

    if options.input == "-":
        lookup_dirs = options.template_dir or ["."]
        lookup = TemplateLookup(lookup_dirs)
        try:
            template = Template(
                sys.stdin.read(),
                lookup=lookup,
                output_encoding=output_encoding,
            )
        except:
            _exit()
    else:
        filename = options.input
        if not isfile(filename):
            raise SystemExit("error: can't find %s" % filename)
        lookup_dirs = options.template_dir or [dirname(filename)]
        lookup = TemplateLookup(lookup_dirs)
        try:
            template = Template(
                filename=filename,
                lookup=lookup,
                output_encoding=output_encoding,
            )
        except:
            _exit()

    kw = dict([varsplit(var) for var in options.var])
    try:
        rendered = template.render(**kw)
    except:
        _exit()
    else:
        if output_file:
            io.open(output_file, "wt", encoding=output_encoding).write(
                rendered
            )
        else:
            sys.stdout.write(rendered)


if __name__ == "__main__":
    cmdline()