merge.py

   1 import sys
   2 import yaml
   3 import argparse
   4
   5 parser = argparse.ArgumentParser()
   6 parser.add_argument('templates', nargs='+')
   7 parser.add_argument('--master-role', nargs='?',
   8                     help='Translate slave_roles to this')
   9 parser.add_argument('--slave-roles', nargs='*',
  10                     help='Translate all of these to master_role')
  11
  12 args = parser.parse_args()
  13
  14 templates = args.templates
  15
  16 def _translate_role(role):
  17     global args
  18     if not args.master_role:
  19         return role
  20     if role == args.master_role:
  21         return role
  22     if role not in args.slave_roles:
  23         return role
  24     return args.master_role
  25
  26 def translate_role(role):
  27     r = _translate_role(role)
  28     if not isinstance(r, basestring):
  29         raise Exception('%s -> %r' % (role, r))
  30     return r
  31
  32 def resolve_params(item, param, value):
  33     if item == {'Ref': param}:
  34         return value
  35     if isinstance(item, dict):
  36         copy_item = dict(item)
  37         for k, v in iter(copy_item.items()):
  38             item[k] = resolve_params(v, param, value)
  39     elif isinstance(item, list):
  40         copy_item = list(item)
  41         new_item = []
  42         for v in copy_item:
  43             new_item.append(resolve_params(v, param, value))
  44         item = new_item
  45     return item
  46
  47
  48 errors = []
  49 end_template={'HeatTemplateFormatVersion': '2012-12-12',
  50               'Description': []}
  51 resource_changes=[]
  52 for template_path in templates:
  53     template = yaml.safe_load(open(template_path))
  54     end_template['Description'].append(template.get('Description',
  55                                                     template_path))
  56     new_parameters = template.get('Parameters', {})
  57     for p, pbody in sorted(new_parameters.items()):
  58         if p in end_template.get('Parameters', {}):
  59             if pbody != end_template['Parameters'][p]:
  60                 errors.append('Parameter %s from %s conflicts.' % (p,
  61                                                                    template_path))
  62             continue
  63         if 'Parameters' not in end_template:
  64             end_template['Parameters'] = {}
  65         end_template['Parameters'][p] = pbody
  66
  67     new_outputs = template.get('Outputs', {})
  68     for o, obody in sorted(new_outputs.items()):
  69         if o in end_template.get('Outputs', {}):
  70             if pbody != end_template['Outputs'][p]:
  71                 errors.append('Output %s from %s conflicts.' % (o,
  72                                                                    template_path))
  73             continue
  74         if 'Outputs' not in end_template:
  75             end_template['Outputs'] = {}
  76         end_template['Outputs'][o] = obody
  77
  78     new_resources = template.get('Resources', {})
  79     for r, rbody in sorted(new_resources.items()):
  80         if rbody['Type'] == 'AWS::EC2::Instance':
  81             # XXX Assuming ImageId is always a Ref
  82             ikey_val = end_template['Parameters'][rbody['Properties']['ImageId']['Ref']]
  83             del end_template['Parameters'][rbody['Properties']['ImageId']['Ref']]
  84             role = rbody.get('Metadata', {}).get('OpenStack::Role', r)
  85             role = translate_role(role)
  86             if role != r:
  87                 resource_changes.append((r, role))
  88             if role in end_template.get('Resources', {}):
  89                 new_metadata = rbody.get('Metadata', {})
  90                 for m, mbody in iter(new_metadata.items()):
  91                     if m in end_template['Resources'][role].get('Metadata', {}):
  92                         if m == 'OpenStack::ImageBuilder::Elements':
  93                             end_template['Resources'][role]['Metadata'][m].extend(mbody)
  94                             continue
  95                         if mbody != end_template['Resources'][role]['Metadata'][m]:
  96                             errors.append('Role %s metadata key %s conflicts.' %
  97                                           (role, m))
  98                         continue
  99                     end_template['Resources'][role]['Metadata'][m] = mbody
 100                 continue
 101             if 'Resources' not in end_template:
 102                 end_template['Resources'] = {}
 103             end_template['Resources'][role] = rbody
 104             ikey = '%sImage' % (role)
 105             end_template['Resources'][role]['Properties']['ImageId'] = {'Ref': ikey}
 106             end_template['Parameters'][ikey] = ikey_val
 107         elif rbody['Type'] == 'FileInclude':
 108             with open(rbody['Path']) as rfile:
 109                 include_content = yaml.safe_load(rfile.read())
 110                 subkeys = rbody.get('SubKey','').split('.')
 111                 while len(subkeys) and subkeys[0]:
 112                     include_content = include_content[subkeys.pop(0)]
 113                 for replace_param, replace_value in iter(rbody.get('Parameters',
 114                                                                    {}).items()):
 115                     include_content = resolve_params(include_content,
 116                                                      replace_param,
 117                                                      replace_value)
 118                 end_template['Resources'][r] = include_content
 119         else:
 120             if r in end_template.get('Resources', {}):
 121                 if rbody != end_template['Resources'][r]:
 122                     errors.append('Resource %s from %s conflicts' % (r,
 123                                                                      template_path))
 124                 continue
 125             if 'Resources' not in end_template:
 126                 end_template['Resources'] = {}
 127             end_template['Resources'][r] = rbody
 128
 129 def fix_ref(item, old, new):
 130     if isinstance(item, dict):
 131         copy_item = dict(item)
 132         for k, v in sorted(copy_item.items()):
 133             if k == 'Ref' and v == old:
 134                 item[k] = new
 135                 continue
 136             if k == 'DependsOn' and v == old:
 137                 item[k] = new
 138                 continue
 139             if k == 'Fn::GetAtt' and isinstance(v, list) and v[0] == old:
 140                 new_list = list(v)
 141                 new_list[0] = new
 142                 item[k] = new_list
 143                 continue
 144             if k == 'AllowedResources' and isinstance(v, list) and old in v:
 145                 while old in v:
 146                     pos = v.index(old)
 147                     v[pos] = new
 148                 continue
 149             fix_ref(v, old, new)
 150     elif isinstance(item, list):
 151         copy_item = list(item)
 152         for v in item:
 153             fix_ref(v, old, new)
 154
 155 for change in resource_changes:
 156     fix_ref(end_template, change[0], change[1])
 157
 158 if errors:
 159     for e in errors:
 160         sys.stderr.write("ERROR: %s\n" % e)
 161 end_template['Description'] = ','.join(end_template['Description'])
 162 sys.stdout.write(yaml.safe_dump(end_template, default_flow_style=False))