descriptor-packages/tools/charm-generator/generator/generators/metadata_generator.py

   1 # Copyright 2019 Whitestack, LLC
   2 #
   3 # Licensed under the Apache License, Version 2.0 (the "License"); you may
   4 # not use this file except in compliance with the License. You may obtain
   5 # a copy of the License at
   6 #
   7 #         http://www.apache.org/licenses/LICENSE-2.0
   8 #
   9 # Unless required by applicable law or agreed to in writing, software
  10 # distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
  11 # WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
  12 # License for the specific language governing permissions and limitations
  13 # under the License.
  14 #
  15 # For those usages not covered by the Apache License, Version 2.0 please
  16 # contact: esousa@whitestack.com or glavado@whitestack.com
  17 ##
  18
  19 import functools
  20 import logging
  21 import os
  22 import sys
  23
  24 import yaml
  25
  26 from jinja2 import Environment, PackageLoader
  27
  28
  29 class MetadataGenerator:
  30     LOGGER = logging.getLogger()
  31     ENV = Environment(loader=PackageLoader('generator.metadata', 'templates'))
  32
  33     def __init__(self, metadata, license=None, options=None):
  34         """
  35         Creates the object to generate the metadata.yaml file from a template.
  36
  37         Usage should be:
  38
  39         1) Create the object.
  40         2) Run the generate method.
  41
  42         :param metadata: metadata information about the charm being generated.
  43         :param license: information license to included in the charm being generated.
  44         :param options: options to override the normal flow.
  45         """
  46         self.path = os.getcwd()
  47         self.metadata = metadata
  48         self.license = license
  49         self.options = options
  50
  51     def generate(self):
  52         """
  53         Generates the metadata.yaml using templates.
  54         """
  55         MetadataGenerator.LOGGER.info('Generating the metadata.yaml...')
  56
  57         standard_metadata = self._read_metadata_yaml()
  58         self._update_metadata(standard_metadata)
  59         self._rename_metadata_yaml_as_backup()
  60         self._write_metadata_yaml()
  61
  62         MetadataGenerator.LOGGER.info('Generated the metadata.yaml.')
  63
  64     def get_metadata(self):
  65         """
  66         Gets the enhanced metadata.
  67
  68         :return: the enhanced metadata dictionary.
  69         """
  70         return self.metadata
  71
  72     def _read_metadata_yaml(self):
  73         """
  74         Reads the values from the old metadata.yaml and does a cleanup on undesired values.
  75         """
  76         MetadataGenerator.LOGGER.debug('Reading old metadata.yaml...')
  77
  78         metadata_yaml_path = self.path + '/metadata.yaml'
  79
  80         if not os.path.isfile(metadata_yaml_path):
  81             MetadataGenerator.LOGGER.error('metadata.yaml must be present. Must be run in the root of the charm')
  82             sys.exit(-1)
  83
  84         with open(metadata_yaml_path, 'r') as f:
  85             metadata = yaml.load(f)
  86
  87         if 'tags' in metadata.keys():
  88             del metadata['tags']
  89         if 'provides' in metadata.keys():
  90             del metadata['provides']
  91         if 'requires' in metadata.keys():
  92             del metadata['requires']
  93         if 'peers' in metadata.keys():
  94             del metadata['peers']
  95
  96         MetadataGenerator.LOGGER.debug('Read old metadata.yaml.')
  97
  98         return metadata
  99
 100     def _update_metadata(self, metadata):
 101         """
 102         Update internal metadata before writing the new metadata.yaml.
 103
 104         :param metadata: metadata values provided by the user.
 105         """
 106         MetadataGenerator.LOGGER.debug('Generating the Ansible Charm...')
 107
 108         if 'name' in metadata:
 109             self.metadata['name'] = metadata['name']
 110             self.metadata['file'] = '%s.py' % metadata['name'].replace('-', '_')
 111
 112         self.metadata['subordinate'] = False
 113         self.metadata['tags'] = ['misc', 'osm', 'vnf']
 114         self.metadata['series'] = ['xenial', 'trusty']
 115
 116         MetadataGenerator.LOGGER.debug('Generating the Ansible Charm...')
 117
 118     def _rename_metadata_yaml_as_backup(self):
 119         """
 120         Renames the metadata.yaml to metadata.yaml.bkp.*.
 121         Preserves the history of the charm for the user.
 122         """
 123         MetadataGenerator.LOGGER.debug('Renaming the metadata.yaml to .bkp.*...')
 124
 125         metadata_yaml_path = self.path + '/metadata.yaml'
 126
 127         ids = [int(f.split('.')[-1]) for f in os.listdir(self.path)
 128                if f.startswith('metadata.yaml.bkp')]
 129
 130         id = 0
 131         if ids:
 132             id = functools.reduce(lambda x, y: x if (x > y) else y, ids)
 133             id += 1
 134
 135         backup_metadata_yaml_path = self.path + ('/metadata.yaml.bkp.%02d' % id)
 136         os.rename(metadata_yaml_path, backup_metadata_yaml_path)
 137
 138         MetadataGenerator.LOGGER.debug('Renamed the metadata.yaml to .bkp.%02d.', id)
 139
 140     def _write_metadata_yaml(self):
 141         """
 142         Writes the enriched metadata to metadata.yaml.
 143         """
 144         MetadataGenerator.LOGGER.debug('Generating metadata.yaml...')
 145
 146         metadata_yaml_path = self.path + '/metadata.yaml'
 147         metadata_yaml_template = MetadataGenerator.ENV.get_template('metadata.yaml.j2')
 148
 149         with open(metadata_yaml_path, 'w') as f:
 150             f.write(metadata_yaml_template.render(metadata=self.metadata, license=self.license))
 151
 152         MetadataGenerator.LOGGER.debug('Generated metadata.yaml.')