sfa/rspecs/elements/versions/pgv2Link.py

   1 from lxml import etree
   2 from sfa.rspecs.elements.link import Link
   3 from sfa.rspecs.elements.interface import Interface
   4 from sfa.rspecs.rspec_elements import RSpecElement, RSpecElements
   5
   6 class PGv2Link:
   7
   8     elements = {
   9         'link': RSpecElement(RSpecElements.LINK, '//default:link | //link'),
  10         'component_manager': RSpecElement(RSpecElements.COMPONENT_MANAGER, './default:component_manager | ./component_manager'),
  11         'link_type': RSpecElement(RSpecElements.LINK_TYPE, './default:link_type | ./link_type'),
  12         'property': RSpecElement(RSpecElements.PROPERTY, './default:property | ./property'),
  13         'interface_ref': RSpecElement(RSpecElements.INTERFACE_REF, './default:interface_ref | ./interface_ref')
  14     }
  15
  16     @staticmethod
  17     def add_links(xml, links):
  18         for link in links:
  19             link_elem = etree.SubElement(xml, 'link')
  20             for attrib in ['component_name', 'component_id', 'client_id']:
  21                 if attrib in link and link[attrib]:
  22                     link_elem.set(attrib, link[attrib])
  23             if 'component_manager' in link and link['component_manager']:
  24                 cm_element = etree.SubElement(link_elem, 'component_manager', name=link['component_manager'])
  25             for if_ref in [link['interface1'], link['interface2']]:
  26                 if_ref_elem = etree.SubElement(link_elem, 'interface_ref')
  27                 for attrib in Interface.fields:
  28                     if attrib in if_ref and if_ref[attrib]:
  29                         if_ref_elem.attrib[attrib] = if_ref[attrib]
  30             prop1 = etree.SubElement(link_elem, 'property', source_id = link['interface1']['component_id'],
  31                 dest_id = link['interface2']['component_id'], capacity=link['capacity'],
  32                 latency=link['latency'], packet_loss=link['packet_loss'])
  33             prop2 = etree.SubElement(link_elem, 'property', source_id = link['interface2']['component_id'],
  34                 dest_id = link['interface1']['component_id'], capacity=link['capacity'],
  35                 latency=link['latency'], packet_loss=link['packet_loss'])
  36             if 'type' in link and link['type']:
  37                 type_elem = etree.SubElement(link_elem, 'link_type', name=link['type'])
  38
  39     @staticmethod
  40     def get_links(xml, namespaces=None):
  41         links = []
  42         link_elems = xml.xpath(PGv2Link.elements['link'].path, namespaces=namespaces)
  43         for link_elem in link_elems:
  44             # set client_id, component_id, component_name
  45             link = Link(link_elem.attrib)
  46             # set component manager
  47             cm = link_elem.xpath('./default:component_manager', namespaces=namespaces)
  48             if len(cm) >  0:
  49                 cm = cm[0]
  50                 if  'name' in cm.attrib:
  51                     link['component_manager'] = cm.attrib['name']
  52             # set link type
  53             link_types = link_elem.xpath(PGv2Link.elements['link_type'].path, namespaces=namespaces)
  54             if len(link_types) > 0:
  55                 link_type = link_types[0]
  56                 if 'name' in link_type.attrib:
  57                     link['type'] = link_type.attrib['name']
  58
  59             # get capacity, latency and packet_loss from first property
  60             props = link_elem.xpath(PGv2Link.elements['property'].path, namespaces=namespaces)
  61             if len(props) > 0:
  62                 prop = props[0]
  63                 for attrib in ['capacity', 'latency', 'packet_loss']:
  64                     if attrib in prop.attrib:
  65                         link[attrib] = prop.attrib[attrib]
  66
  67             # get interfaces
  68             if_elems = link_elem.xpath(PGv2Link.elements['interface_ref'].path, namespaces=namespaces)
  69             ifs = []
  70             for if_elem in if_elems:
  71                 if_ref = Interface(if_elem.attrib)
  72                 ifs.append(if_ref)
  73             if len(ifs) > 1:
  74                 link['interface1'] = ifs[0]
  75                 link['interface2'] = ifs[1]
  76             links.append(link)
  77         return links
  78