Allow passing optional SLA (Service Level Agreement)

It is important during the request to being able to specify SLA, as current,
fully random selection does not allow fine grained control of partition
selection.

slapos/slap/slap.py

@@ -149,7 +149,7 @@ class OpenOrder(SlapDocument):
   zope.interface.implements(interface.IOpenOrder)
 
   def request(self, software_release, partition_reference,
-      partition_parameter_kw=None, software_type=None):
+      partition_parameter_kw=None, software_type=None, sla_parameter_kw=None):
     if partition_parameter_kw is None:
       partition_parameter_kw = {}
     request_dict = {
@@ -159,6 +159,9 @@ class OpenOrder(SlapDocument):
       }
     if software_type is not None:
       request_dict['software_type'] = software_type
+    if sla_parameter_kw is not None:
+      request_dict['sla_parameter_xml'] = xml_marshaller.dumps(
+        sla_parameter_kw)
     self._connection_helper.POST('/requestComputerPartition', request_dict)
     xml = self._connection_helper.response.read()
     software_instance = xml_marshaller.loads(xml)
@@ -279,7 +282,8 @@ class ComputerPartition(SlapDocument):
   #      Computer Partition data are fetch from server shall be delayed
   @_syncComputerPartitionInformation
   def request(self, software_release, software_type, partition_reference,
-              shared=False, partition_parameter_kw=None, filter_kw=None):
+              shared=False, partition_parameter_kw=None, filter_kw=None,
+              sla_parameter_kw=None):
     if partition_parameter_kw is None:
       partition_parameter_kw = {}
     elif not isinstance(partition_parameter_kw, dict):
@@ -292,8 +296,7 @@ class ComputerPartition(SlapDocument):
       raise ValueError("Unexpected type of filter_kw '%s'" % \
                        filter_kw)
 
-    self._connection_helper.POST('/requestComputerPartition',
-      { 'computer_id': self._computer_id,
+    request_dict = { 'computer_id': self._computer_id,
         'computer_partition_id': self._partition_id,
         'software_release': software_release,
         'software_type': software_type,
@@ -302,7 +305,11 @@ class ComputerPartition(SlapDocument):
         'partition_parameter_xml': xml_marshaller.dumps(
                                         partition_parameter_kw),
         'filter_xml': xml_marshaller.dumps(filter_kw),
-      })
+      }
+    if sla_parameter_kw is not None:
+      request_dict['sla_parameter_xml'] = xml_marshaller.dumps(
+        sla_parameter_kw)
+    self._connection_helper.POST('/requestComputerPartition', request_dict)
     xml = self._connection_helper.response.read()
     software_instance = xml_marshaller.loads(xml)
     computer_partition = ComputerPartition(