proxy: Update timestamp partition on slave changes

Each time slave partition changes (it is added or updated) the master
partition timestamp has to be recalculated.

/reviewed-on nexedi/slapos.core!176

slapos/proxy/views.py

@@ -756,23 +756,35 @@ def requestSlave(software_release, software_type, partition_reference, partition
     new_slave[key] = partition_parameter_kw[key]
 
   # Add slave to partition slave_list if not present else replace information
+  slave_updated_or_added = False
   slave_instance_list = partition['slave_instance_list']
   if slave_instance_list:
     slave_instance_list = loads(slave_instance_list.encode('utf-8'))
     for i, x in enumerate(slave_instance_list):
       if x['slave_reference'] == slave_reference:
-        slave_instance_list[i] = new_slave
+        if slave_instance_list[i] != new_slave:
+          slave_instance_list[i] = new_slave
+          slave_updated_or_added = True
         break
     else:
       slave_instance_list.append(new_slave)
+      slave_updated_or_added = True
   else:
     slave_instance_list = [new_slave]
+    slave_updated_or_added = True
 
+  q += ' WHERE reference=? AND computer_reference=?'
+  a(partition['reference'])
+  a(partition['computer_reference'])
   # Update slave_instance_list in database
   args = []
   a = args.append
   q = 'UPDATE %s SET slave_instance_list=?'
   a(bytes2str(dumps(slave_instance_list)))
+  if slave_updated_or_added:
+    timestamp = time.time()
+    q += ', timestamp=?'
+    a(timestamp)
   q += ' WHERE reference=? and computer_reference=?'
   a(partition['reference'])
   a(requested_computer_id)

slapos/tests/test_slapproxy.py

@@ -870,6 +870,53 @@ class TestSlaveRequest(MasterMixin):
     master_partition = self.getPartitionInformation(master_partition_id)
     self.assertEqual(len(master_partition._parameter_dict['slave_instance_list']), 0)
 
+  def test_slave_request_updates_timestamp(self):
+    self.format_for_number_of_partitions(1)
+    # Provide partition
+    master_partition = self.request('http://sr//', None, 'MyMasterInstance', 'slappart4')
+
+    def getPartition():
+      return self.getFullComputerInformation()._computer_partition_list[0]
+
+    def getTimestamp(partition):
+      return float(partition._parameter_dict['timestamp'])
+
+    before = getPartition()
+    before_timestamp = getTimestamp(before)
+    self.assertEqual(len(before._parameter_dict['slave_instance_list']), 0)
+    time.sleep(0.1)
+
+    self.request('http://sr//', None, 'MyFirstSlave', shared=True)
+    after = getPartition()
+    after_timestamp = getTimestamp(after)
+    self.assertEqual(len(after._parameter_dict['slave_instance_list']), 1)
+    self.assertLess(before_timestamp, after_timestamp, 'Adding first slave shall change the timestamp')
+
+    before_timestamp = after_timestamp
+    time.sleep(0.1)
+    self.request('http://sr//', None, 'MySecondSlave', shared=True)
+    after = getPartition()
+    after_timestamp = getTimestamp(after)
+    self.assertEqual(len(after._parameter_dict['slave_instance_list']), 2)
+    self.assertLess(before_timestamp, after_timestamp, 'Adding second slave shall change the timestamp')
+
+    before_timestamp = after_timestamp
+    time.sleep(0.1)
+    self.request('http://sr//', None, 'MySecondSlave', shared=True, partition_parameter_kw={'a':'b'})
+    after = getPartition()
+    after_timestamp = getTimestamp(after)
+    self.assertEqual(len(after._parameter_dict['slave_instance_list']), 2)
+    self.assertLess(before_timestamp, after_timestamp, 'Updating any slave shall change the timestamp')
+
+    before_timestamp = after_timestamp
+    time.sleep(0.1)
+    self.request('http://sr//', None, 'MySecondSlave', shared=True, partition_parameter_kw={'a':'b'})
+    after = getPartition()
+    after_timestamp = getTimestamp(after)
+    self.assertEqual(len(after._parameter_dict['slave_instance_list']), 2)
+    self.assertEqual(before_timestamp, after_timestamp, 'No-op change of the slave shall not change the timestamp')
+
+
   def test_slave_request_set_parameters_are_updated(self):
     """
     Parameters sent in slave request must be put in slave master