sfa/methods/resolve.py

   1 ### $Id$
   2 ### $URL$
   3 import traceback
   4 from sfa.util.faults import *
   5 from sfa.util.method import Method
   6 from sfa.util.parameter import Parameter, Mixed
   7 from sfa.trust.auth import Auth
   8 from sfa.util.record import GeniRecord
   9 from sfa.util.genitable import GeniTable
  10 from sfa.util.debug import log
  11 from sfa.server.registry import Registries
  12 from sfa.util.prefixTree import prefixTree
  13 from sfa.trust.credential import Credential
  14
  15 class resolve(Method):
  16     """
  17     Resolve a record.
  18
  19     @param cred credential string authorizing the caller
  20     @param hrn human readable name to resolve
  21     @return a list of record dictionaries or empty list
  22     """
  23
  24     interfaces = ['registry']
  25
  26     accepts = [
  27         Parameter(str, "Credential string"),
  28         Parameter(str, "Human readable name (hrn)")
  29         ]
  30
  31     returns = [GeniRecord]
  32
  33     def call(self, cred, hrn, origin_hrn=None):
  34         user_cred = Credential(string=cred)
  35
  36         #log the call
  37         if not origin_hrn:
  38             origin_hrn = user_cred.get_gid_caller().get_hrn()
  39         self.api.logger.info("interface: %s\tcaller-hrn: %s\ttarget-hrn: %s\tmethod-name: %s"%(self.api.interface, origin_hrn, hrn, self.name))
  40
  41         # validate the cred
  42         self.api.auth.check(cred, 'resolve')
  43
  44         # load all know registry names into a prefix tree and attempt to find
  45         # the longest matching prefix
  46         good_records = []
  47         registries = Registries(self.api)
  48         hrns = registries.keys()
  49         tree = prefixTree()
  50         tree.load(hrns)
  51         registry_hrn = tree.best_match(hrn)
  52
  53         #if there was no match then this record belongs to an unknow registry
  54         if not registry_hrn:
  55             raise MissingAuthority(hrn)
  56
  57         # if the best match (longest matching hrn) is not the local registry,
  58         # forward the request
  59         if registry_hrn != self.api.hrn:
  60             credential = self.api.getCredential()
  61             records = registries[registry_hrn].resolve(credential, hrn, origin_hrn)
  62             good_records = [GeniRecord(dict=record).as_dict() for record in records]
  63         if good_records:
  64             return good_records
  65
  66         # if we still havnt found the record yet, try the local registry
  67         table = GeniTable()
  68         records = table.findObjects(hrn)
  69         if not records:
  70             raise RecordNotFound(hrn)
  71         for record in records:
  72             try:
  73                 self.api.fill_record_info(record)
  74                 good_records.append(dict(record))
  75             except PlanetLabRecordDoesNotExist:
  76                 # silently drop the ones that are missing in PL
  77                 print >> log, "ignoring geni record ", record['hrn'], \
  78                               " because pl record does not exist"
  79                 table.remove(record)
  80
  81
  82         return good_records
  83