lorax/utils/test-parse-template

#!/usr/bin/python3
# test-parse-template - parse and print (but don't execute!) a Lorax Template.
# Copyright (C) 2011-2015  Red Hat, Inc.
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.
#
# Red Hat Author(s):  Will Woods <wwoods@redhat.com>

import sys, inspect
from pylorax.base import DataHolder
from pylorax.ltmpl import LoraxTemplate
from mako.exceptions import text_error_template

data = DataHolder()
data.arch = DataHolder(basearch='ARCH.BASEARCH', buildarch='ARCH.BUILDARCH', libdir='ARCH.LIBDIR')
data.product = DataHolder(name='PRODUCT.NAME', version='PRODUCT.VERSION')
data.glob = lambda g: ['glob.1', 'glob.2']
data.exists = lambda e: True
data.udev = lambda s: "UDEV_ESCAPE(%s)" % s.upper()
data.removelocales = ['REMOVELOCALE1', 'REMOVELOCALE2']
data.kernels = [DataHolder(path="/path/to/vmlinuz", initrd=DataHolder(path="/path/to/initrd.img"), flavor=None, arch=data.arch.basearch)]
data.basearch = data.arch.basearch
data.libdir = data.arch.libdir

def get_args(template):
    sig = inspect.signature(template.module.render_body)
    return set(list(sig.parameters)[1:]) # skip "context"

def readtemplate(filename):
    parser = LoraxTemplate(directories=['.'])
    from mako.lookup import TemplateLookup
    lookup = TemplateLookup(directories=parser.directories)
    return lookup.get_template(filename)

if __name__ == '__main__':
    # check args
    if len(sys.argv) == 1:
        print("usage: %s TEMPLATE [arg1=value1] [arg2=value2] ...")

    # read template
    templatefile = sys.argv[1]
    print("parsing %s" % templatefile)
    t = readtemplate(templatefile)
    reqargs = get_args(t)
    print("required args: %s" % ' '.join(reqargs))

    # parse extra commandline args
    if len(sys.argv) > 2:
        for arg in sys.argv[2:]:
            if '=' in arg:
                k,v = arg.split('=',1)
                data[k] = v

    # fill in remaining blanks
    for a in reqargs.difference(data):
        data[a] = a.upper()

    print("rendering %s using values:" % templatefile)
    for a in data:
        print("  %s=%s" % (a,repr(data[a])))

    # render and print
    try:
        lines = t.render(**data).splitlines()
        for line in lines:
            print(line)
    except Exception:
        print(text_error_template().render())
        raise SystemExit(1)