Source Code for Module occi.protocol.json_rendering

  1  # coding=utf-8
 
  2  #
 
  3  # Copyright (C) 2010-2012 Platform Computing
 
  4  #
 
  5  # This library is free software; you can redistribute it and/or
 
  6  # modify it under the terms of the GNU Lesser General Public
 
  7  # License as published by the Free Software Foundation; either
 
  8  # version 2.1 of the License, or (at your option) any later version.
 
  9  #
 
 10  # This library is distributed in the hope that it will be useful,
 
 11  # but WITHOUT ANY WARRANTY; without even the implied warranty of
 
 12  # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 
 13  # Lesser General Public License for more details.
 
 14  #
 
 15  # You should have received a copy of the GNU Lesser General Public
 
 16  # License along with this library; if not, write to the Free Software
 
 17  # Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301 USA
 
 18  #
 
 19  
 
 20  '''
 
 21  JSON based rendering.
 
 22  
 
 23  Created on 01.02.2012
 
 24  
 
 25  @author: tmetsch
 
 26  ''' 
 27  
 
 28  # L8R: check if this can be move partly to occi_rendering (once standardized)
 
 29  # and rename to a parser class.
 
 30  
 
 31  # disabling 'Method is abstract' pylint check (currently only support GETs!)
 
 32  # pylint: disable=W0223
 
 33  
 
 34  from occi.core_model import Resource 
 35  from occi.handlers import CONTENT_TYPE 
 36  from occi.protocol.rendering import Rendering 
 37  import json 
 38  
 
 39  
 
 40 -def _from_category(category): 
 41      '''
 
 42      Create a JSON struct for a category.
 
 43      ''' 
 44      data = {'term': category.term, 'scheme': category.scheme} 
 45      if hasattr(category, 'title') and category.title is not '': 
 46          data['title'] = category.title 
 47      if hasattr(category, 'related') and len(category.related) > 0: 
 48          rel_list = [] 
 49          for item in category.related: 
 50              rel_list.append(str(item)) 
 51          data['related'] = rel_list 
 52      if hasattr(category, 'location') and category.location is not None: 
 53          data['location'] = category.location 
 54      if hasattr(category, 'attributes') and len(category.attributes) >= 1: 
 55          attr_list = {} 
 56          for item in category.attributes: 
 57              if category.attributes[item] == 'required': 
 58                  attr_list[item] = 'required' 
 59              elif category.attributes[item] == 'immutable': 
 60                  attr_list[item] = 'immutable' 
 61              else: 
 62                  attr_list[item] = 'muttable' 
 63          data['attributes'] = attr_list 
 64      if hasattr(category, 'actions') and len(category.actions) > 0: 
 65          action_list = [] 
 66          for item in category.actions: 
 67              action_list.append(str(item)) 
 68          data['actions'] = action_list 
 69      return data 
 70  
 
 71  
 
 72 -def _from_entity(entity): 
 73      '''
 
 74      Create a JSON struct for an entity.
 
 75      ''' 
 76      data = {'kind': _from_category(entity.kind)} 
 77      # kind
 
 78  
 
 79      # mixins
 
 80      mixins = [] 
 81      for mixin in entity.mixins: 
 82          tmp = _from_category(mixin) 
 83          mixins.append(tmp) 
 84      data['mixins'] = mixins 
 85  
 
 86      # actions
 
 87      actions = [] 
 88      for action in entity.actions: 
 89          tmp = {'kind': _from_category(action), 'link': entity.identifier +
 
 90                 '?action=' + action.term} 
 91          actions.append(tmp) 
 92      data['actions'] = actions 
 93  
 
 94      # links
 
 95      if isinstance(entity, Resource): 
 96          links = [] 
 97          for link in entity.links: 
 98              tmp = _from_entity(link) 
 99              tmp['source'] = link.source.identifier 
100              tmp['target'] = link.target.identifier 
101              links.append(tmp) 
102          data['links'] = links 
103  
 
104      # attributes
 
105      attr = {} 
106      for attribute in entity.attributes: 
107          attr[attribute] = entity.attributes[attribute] 
108      data['attributes'] = attr 
109  
 
110      return data 
111  
 
112  
 
113 -class JsonRendering(Rendering): 
114      '''
 
115      This is a rendering which will use the HTTP header to place the information
 
116      in an syntax and semantics as defined in the OCCI specification.
 
117      ''' 
118  
 
119      mime_type = 'application/occi+json' 
120  
 
121 -    def from_entity(self, entity): 
122          data = _from_entity(entity) 
123  
 
124          body = json.dumps(data, sort_keys=True, indent=2) 
125          return {CONTENT_TYPE: self.mime_type}, body 
126  
 
127 -    def from_entities(self, entities, key): 
128          data = [] 
129          for item in entities: 
130              data.append(_from_entity(item)) 
131  
 
132          body = json.dumps(data, sort_keys=True, indent=2) 
133          return {CONTENT_TYPE: self.mime_type}, body 
134  
 
135 -    def from_categories(self, categories): 
136          data = [] 
137          for item in categories: 
138              data.append(_from_category(item)) 
139  
 
140          body = json.dumps(data, sort_keys=True, indent=2) 
141          return {CONTENT_TYPE: self.mime_type}, body 
142