sfa/rspecs/elements/versions/pgv2Link.py

   1 from lxml import etree
   2 from sfa.util.plxrn import PlXrn
   3 from sfa.util.xrn import Xrn
   4 from sfa.rspecs.elements.link import Link
   5 from sfa.rspecs.elements.interface import Interface
   6 from sfa.rspecs.rspec_elements import RSpecElement, RSpecElements
   7
   8 class PGv2Link:
   9
  10     elements = {
  11         'link': RSpecElement(RSpecElements.LINK, '//default:link | //link'),
  12         'component_manager': RSpecElement(RSpecElements.COMPONENT_MANAGER, './default:component_manager | ./component_manager'),
  13         'link_type': RSpecElement(RSpecElements.LINK_TYPE, './default:link_type | ./link_type'),
  14         'property': RSpecElement(RSpecElements.PROPERTY, './default:property | ./property'),
  15         'interface_ref': RSpecElement(RSpecElements.INTERFACE_REF, './default:interface_ref | ./interface_ref')
  16     }
  17
  18     @staticmethod
  19     def add_links(xml, links):
  20         root = xml.root
  21         for link in links:
  22             link_elem = etree.SubElement(root, 'link')
  23             for attrib in ['component_name', 'component_id', 'client_id']:
  24                 if attrib in link and link[attrib]:
  25                     link_elem.set(attrib, link[attrib])
  26             if 'component_manager' in link and link['component_manager']:
  27                 cm_element = etree.SubElement(link_elem, 'component_manager', name=link['component_manager'])
  28             for if_ref in [link['interface1'], link['interface2']]:
  29                 if_ref_elem = etree.SubElement(link_elem, 'interface_ref')
  30                 for attrib in Interface.fields:
  31                     if attrib in if_ref and if_ref[attrib]:
  32                         if_ref_elem.attrib[attrib] = if_ref[attrib]
  33             prop1 = etree.SubElement(link_elem, 'property', source_id = link['interface1']['component_id'],
  34                 dest_id = link['interface2']['component_id'], capacity=link['capacity'],
  35                 latency=link['latency'], packet_loss=link['packet_loss'])
  36             prop2 = etree.SubElement(link_elem, 'property', source_id = link['interface2']['component_id'],
  37                 dest_id = link['interface1']['component_id'], capacity=link['capacity'],
  38                 latency=link['latency'], packet_loss=link['packet_loss'])
  39             if 'type' in link and link['type']:
  40                 type_elem = etree.SubElement(link_elem, 'link_type', name=link['type'])
  41
  42     @staticmethod
  43     def get_links(xml):
  44         links = []
  45         link_elems = xml.xpath(PGv2Link.elements['link'].path, namespaces=xml.namespaces)
  46         for link_elem in link_elems:
  47             # set client_id, component_id, component_name
  48             link = Link(link_elem.attrib, link_elem)
  49             # set component manager
  50             cm = link_elem.xpath('./default:component_manager', namespaces=xml.namespaces)
  51             if len(cm) >  0:
  52                 cm = cm[0]
  53                 if  'name' in cm.attrib:
  54                     link['component_manager'] = cm.attrib['name']
  55             # set link type
  56             link_types = link_elem.xpath(PGv2Link.elements['link_type'].path, namespaces=xml.namespaces)
  57             if len(link_types) > 0:
  58                 link_type = link_types[0]
  59                 if 'name' in link_type.attrib:
  60                     link['type'] = link_type.attrib['name']
  61
  62             # get capacity, latency and packet_loss from first property
  63             props = link_elem.xpath(PGv2Link.elements['property'].path, namespaces=xml.namespaces)
  64             if len(props) > 0:
  65                 prop = props[0]
  66                 for attrib in ['capacity', 'latency', 'packet_loss']:
  67                     if attrib in prop.attrib:
  68                         link[attrib] = prop.attrib[attrib]
  69
  70             # get interfaces
  71             if_elems = link_elem.xpath(PGv2Link.elements['interface_ref'].path, namespaces=xml.namespaces)
  72             ifs = []
  73             for if_elem in if_elems:
  74                 if_ref = Interface(if_elem.attrib, if_elem)
  75                 ifs.append(if_ref)
  76             if len(ifs) > 1:
  77                 link['interface1'] = ifs[0]
  78                 link['interface2'] = ifs[1]
  79             links.append(link)
  80         return links
  81
  82     @staticmethod
  83     def add_link_requests(xml, link_tuples, append=False):
  84         if not isinstance(link_tuples, set):
  85             link_tuples = set(link_tuples)
  86
  87         available_links = PGv2Link.get_links(xml)
  88         recently_added = []
  89         for link in available_links:
  90             auth = Xrn(link['component_id']).get_authority_hrn()
  91             if_name1 =  Xrn(link['interface1']['component_id']).get_leaf()
  92             if_name2 =  Xrn(link['interface2']['component_id']).get_leaf()
  93
  94             requested_link = None
  95             l_tup_1 = (if_name1, if_name2)
  96             l_tup_2 = (if_name2, if_name1)
  97             if link_tuples.issuperset([(if_name1, if_name2)]):
  98                 requested_link = (if_name1, if_name2)
  99             elif link_tuples.issuperset([(if_name2, if_name2)]):
 100                 requested_link = (if_name2, if_name1)
 101
 102             if requested_link:
 103                 # add client id to link ane interface elements
 104                 link.element.set('client_id', link['component_name'])
 105                 link['interface1'].element.set('client_id', Xrn(link['interface1']['component_id']).get_leaf())
 106                 link['interface2'].element.set('client_id', Xrn(link['interface2']['component_id']).get_leaf())
 107                 recently_added.append(link['component_name'])
 108
 109         if not append:
 110             # remove all links that don't have a client id
 111             for link in PGv2Link.get_links(xml):
 112                 if not link['client_id'] or link['component_name'] not in recently_added:
 113                     parent = link.element.getparent()
 114                     parent.remove(link.element)
 115
 116     @staticmethod
 117     def get_link_requests(xml):
 118         link_requests = []
 119         for link in PGv2Link.get_links(xml):
 120             if link['client_id']:
 121                 link_requests.append(link)
 122         return link_requests