sonic-buildimage/src/sonic-config-engine/sonic-cfggen

#!/usr/bin/env python

import sys
import os.path
import argparse
import yaml
import jinja2
import netaddr
import json
from minigraph import parse_xml


def is_ipv4(value):
    if not value:
        return False
    if isinstance(value, netaddr.IPAddress):
        addr = value
    else:
        try:
            addr = netaddr.IPAddress(str(value))
        except:
            return False
    return addr.version == 4

def is_ipv6(value):
    if not value:
        return False
    if isinstance(value, netaddr.IPAddress):
        addr = value
    else:
        try:
            addr = netaddr.IPAddress(str(value))
        except:
            return False
    return addr.version == 6

def get_machine_info():
    if not os.path.isfile('/host/machine.conf'):
        return None
    machine_vars = {}
    with open('/host/machine.conf') as machine_file:
        for line in machine_file:
            tokens = line.split('=')
            if len(tokens) < 2:
                continue
            machine_vars[tokens[0]] = tokens[1].strip()
    return machine_vars    


def main():
    parser=argparse.ArgumentParser(description="Render configuration file from minigraph data and jinja2 template.")
    parser.add_argument("-m", "--minigraph", help="minigraph xml file")
    parser.add_argument("-y", "--yaml", help="yaml file that contains addtional variables")
    parser.add_argument("-a", "--additional-data", help="addition data, in json string")
    group = parser.add_mutually_exclusive_group()
    group.add_argument("-t", "--template", help="render the data with the template file")
    group.add_argument("-s", "--alias-mapping", help="print alias mapping json if available", action='store_true')
    group.add_argument("-v", "--var", help="print the value of a variable")
    group.add_argument("--var-json", help="print the value of a variable, in json format")
    group.add_argument("--var-keys", help="print all keys of a map variable")
    group.add_argument("--print-data", help="print all data", action='store_true')
    args = parser.parse_args()

    data = {}
    machine_info = get_machine_info()
    if machine_info != None:
        data.update(machine_info)
        if machine_info.has_key('onie_platform'):
            data['platform'] = machine_info['onie_platform']
        elif machine_info.has_key('aboot_platform'):
            data['platform'] = machine_info['aboot_platform']

    if args.minigraph != None:
        minigraph = args.minigraph
        if data.has_key('platform'):
            data.update(parse_xml(minigraph, data['platform']))
        else:
            data.update(parse_xml(minigraph))

    if args.yaml != None:
        with open(args.yaml, 'r') as stream:
            additional_data = yaml.load(stream)      
            data.update(additional_data)

    if args.additional_data != None:
        data.update(json.loads(args.additional_data))

    if args.template != None:
        template_file = os.path.abspath(args.template)
        env = jinja2.Environment(loader=jinja2.FileSystemLoader('/'), trim_blocks=True)
        env.filters['ipv4'] = is_ipv4
        env.filters['ipv6'] = is_ipv6
        template = env.get_template(template_file)
        print template.render(data)
    
    if args.var != None:
        print data[args.var]

    if args.var_json != None:
        print json.dumps(data[args.var_json])

    if args.var_keys != None:
        for key in data[args.var_keys].keys():
          print key
    
    if args.alias_mapping:
        mapping = {}
        if data.has_key('alias_map'):
            for item in data['alias_map']:
                mapping[item['sonic']] = item['origin']
        print json.dumps(mapping)

    if args.print_data:
        print data

if __name__ == "__main__":
    main()