standalone: Avoid overwriting slapformat config

Some configuration in `slapos.cfg` and `slapformat-definition.cfg`
is updated by calling the `format` method, but was initialised to
hardcoded and even invalid values in the constructor. This meant
that calling the constructor again would overwrite the valid config.

slapos/slap/standalone.py

@@ -37,6 +37,7 @@ import pwd
 
 from six.moves import urllib
 from six.moves import http_client
+from six.moves import configparser
 
 try:
   import subprocess32 as subprocess
@@ -410,7 +411,6 @@ class StandaloneSlapOS(object):
     self._base_directory = base_directory
     self._shared_part_list = list(shared_part_list)
     self._partition_forward_configuration = list(partition_forward_configuration)
-    self._partition_count = 0
     self._partition_base_name = 'slappart'
     self._ipv4_address = None
     self._ipv6_address = None
@@ -529,9 +529,16 @@ class StandaloneSlapOS(object):
 
     self._supervisor_socket = os.path.join(run_directory, 'sv.sock')
 
+    slapos_configp = configparser.SafeConfigParser()
+    slapos_configp.read(self._slapos_config)
+    try:
+      self._partition_count = slapos_configp.get('slapformat', 'partition_amount')
+    except configparser.Error:
+      self._partition_count = 0
+
     SupervisorConfigWriter(self).writeConfig(self._supervisor_config)
     SlapOSConfigWriter(self).writeConfig(self._slapos_config)
-    SlapformatDefinitionWriter(self).writeConfig(self._slapformat_definition)
+    # SlapformatDefinitionWriter(self).writeConfig(self._slapformat_definition)
     SlapOSCommandWriter(self).writeConfig(self._slapos_wrapper)
     SlapOSNodeAutoWriter(self).writeConfig(self._slapos_node_auto_bin)
 

slapos/tests/test_standalone.py

@@ -181,6 +181,8 @@ class TestSlapOSStandaloneSetup(unittest.TestCase):
       self.assertEqual(partition_count, len(partitions))
       for path in partitions:
         shutil.rmtree(path)
+      # call constructor again to see if it breaks the configuration
+      StandaloneSlapOS(working_dir, SLAPOS_TEST_IPV4, SLAPOS_TEST_PORT)
       subprocess.check_call(format_command)
       self.assertEqual(partition_count, len(glob.glob(glob_pattern)))