Introduce new garbage collector for instances ignored by buildout

Buildout cannot request destroy sub instances when it is removed from
instance parameters by the user. Ex: request a cluster of KVM, with
kvm1 and kvm2 instances, edit parameters and remove kvm2 in the list.
Buildout will just ignore that instance and it will be removed only when
the hosting subscription will be destroyed.

                 -- kvm1
root instance --|
                 -X- kvm2

So when processing a partition, we send to master the list of requested sub
instance(s). If the previous list was ['kvm1', 'kvm2'], then after remove kvm2
the list will be ['kvm1'] (for the root instance). Commit this list to the
master will unlink between root instance and kvm2 (predecessor categorie).

A new alarm will search for unlinked instances: Instance which has no parent,
and destroy them (also destroy the sub tree).

master/bt5/slapos_slap_tool/TestTemplateItem/portal_components/test.erp5.testSlapOSSlapTool.py

@@ -1635,6 +1635,123 @@ class TestSlapOSSlapToolInstanceAccess(TestSlapOSSlapToolMixin):
       if os.path.exists(self.instance_request_simulator):
         os.unlink(self.instance_request_simulator)
 
+  def test_updateInstancePredecessorList(self):
+    self._makeComplexComputer()
+
+    partition_id = self.start_requested_software_instance.getAggregateValue(
+        portal_type='Computer Partition').getReference()
+    self.login(self.start_requested_software_instance.getReference())
+
+    # Atach two software instances
+    instance_kw = dict(
+      software_release='http://a.release',
+      software_type='type',
+      instance_xml=self.generateSafeXml(),
+      sla_xml=self.generateSafeXml(),
+      shared=False,
+      software_title='Instance0',
+      state='started'
+    )
+    self.start_requested_software_instance.requestInstance(**instance_kw)
+    instance_kw['software_title'] = 'Instance1'
+    self.start_requested_software_instance.requestInstance(**instance_kw)
+    self.tic()
+
+    self.assertEqual(len(self.start_requested_software_instance.getPredecessorList()), 2)
+    self.assertSameSet(['Instance0', 'Instance1'],
+            self.start_requested_software_instance.getPredecessorTitleList())
+
+    # Update with no changes
+    instance_list_xml = """
+<marshal>
+  <list id="i2"><string>Instance0</string><string>Instance1</string></list>
+</marshal>"""
+    self.portal_slap.updateComputerPartitionRelatedInstanceList(
+        computer_id=self.computer_id,
+        computer_partition_id=partition_id,
+        instance_reference_xml=instance_list_xml)
+    self.tic()
+    self.assertSameSet(['Instance0', 'Instance1'],
+            self.start_requested_software_instance.getPredecessorTitleList())
+
+    # Update Instance0 was not requested
+    instance_list_xml = """
+<marshal>
+  <list id="i2"><string>Instance1</string></list>
+</marshal>"""
+    self.portal_slap.updateComputerPartitionRelatedInstanceList(
+        computer_id=self.computer_id,
+        computer_partition_id=partition_id,
+        instance_reference_xml=instance_list_xml)
+    self.tic()
+    self.assertSameSet(['Instance1'],
+            self.start_requested_software_instance.getPredecessorTitleList())
+
+  def test_updateInstancePredecessorList_one_child(self):
+    self._makeComplexComputer()
+
+    partition_id = self.start_requested_software_instance.getAggregateValue(
+        portal_type='Computer Partition').getReference()
+    self.login(self.start_requested_software_instance.getReference())
+
+    # Atach one software instance
+    instance_kw = dict(
+      software_release='http://a.release',
+      software_type='type',
+      instance_xml=self.generateSafeXml(),
+      sla_xml=self.generateSafeXml(),
+      shared=False,
+      software_title='Instance0',
+      state='started'
+    )
+    self.start_requested_software_instance.requestInstance(**instance_kw)
+    self.tic()
+
+    self.assertEqual(len(self.start_requested_software_instance.getPredecessorList()), 1)
+    self.assertSameSet(['Instance0'],
+            self.start_requested_software_instance.getPredecessorTitleList())
+
+    instance_list_xml = '<marshal><list id="i2" /></marshal>'
+    self.portal_slap.updateComputerPartitionRelatedInstanceList(
+        computer_id=self.computer_id,
+        computer_partition_id=partition_id,
+        instance_reference_xml=instance_list_xml)
+    self.tic()
+    self.assertEqual([],
+              self.start_requested_software_instance.getPredecessorTitleList())
+
+  def test_updateInstancePredecessorList_no_child(self):
+    self._makeComplexComputer()
+
+    partition_id = self.start_requested_software_instance.getAggregateValue(
+        portal_type='Computer Partition').getReference()
+    self.login(self.start_requested_software_instance.getReference())
+
+    self.assertEqual([],
+            self.start_requested_software_instance.getPredecessorTitleList())
+
+    instance_list_xml = '<marshal><list id="i2" /></marshal>'
+    self.portal_slap.updateComputerPartitionRelatedInstanceList(
+        computer_id=self.computer_id,
+        computer_partition_id=partition_id,
+        instance_reference_xml=instance_list_xml)
+    self.tic()
+    self.assertEqual([],
+              self.start_requested_software_instance.getPredecessorTitleList())
+
+    # Try with something that doesn't exist
+    instance_list_xml = """
+<marshal>
+<list id="i2"><string>instance0</string></list>
+</marshal>"""
+    self.portal_slap.updateComputerPartitionRelatedInstanceList(
+        computer_id=self.computer_id,
+        computer_partition_id=partition_id,
+        instance_reference_xml=instance_list_xml)
+    self.tic()
+    self.assertEqual([],
+              self.start_requested_software_instance.getPredecessorTitleList())
+
   def test_availableComputerPartition(self):
     self._makeComplexComputer()
     partition_id = self.start_requested_software_instance.getAggregateValue(

master/product/Vifib/Tool/SlapTool.py

@@ -517,6 +517,18 @@ class SlapTool(BaseTool):
                                                    connection_xml,
                                                    slave_reference)
 
+  security.declareProtected(Permissions.AccessContentsInformation,
+    'updateComputerPartitionRelatedInstanceList')
+  def updateComputerPartitionRelatedInstanceList(self, computer_id,
+                                                   computer_partition_id,
+                                                   instance_reference_xml):
+    """
+    Update Software Instance predecessor list
+    """
+    return self._updateComputerPartitionRelatedInstanceList(computer_id,
+                                                   computer_partition_id,
+                                                   instance_reference_xml)
+
   security.declareProtected(Permissions.AccessContentsInformation,
     'supplySupply')
   def supplySupply(self, url, computer_id, state='available'):
@@ -1358,6 +1370,44 @@ class SlapTool(BaseTool):
         software_instance._instance_guid = instance_guid
         return xml_marshaller.xml_marshaller.dumps(software_instance)
 
+  @UnrestrictedMethod
+  def _updateComputerPartitionRelatedInstanceList(self, computer_id,
+                              computer_partition_id, instance_reference_xml):
+    """
+    Update Software Instance predecessor list to match the given list. If one
+    instance was not requested by this computer partition, it should be removed
+    in the predecessor_list of this instance.
+    Once the link is removed, this instance will be trashed by Garbage Collect!
+
+    instance_reference_xml contain list of title of sub-instances requested by
+    this instance.
+    """
+    software_instance_document = self.\
+                          _getSoftwareInstanceForComputerPartition(computer_id,
+                          computer_partition_id)
+
+    cache_reference = '%s-PREDLIST' % software_instance_document.getReference()
+    if self._getLastData(cache_reference) != instance_reference_xml:
+      instance_reference_list = xml_marshaller.xml_marshaller.loads(
+                                                        instance_reference_xml)
+
+      current_predecessor_list = software_instance_document.getPredecessorValueList(
+                            portal_type=['Software Instance', 'Slave Instance'])
+      current_predecessor_title_list = [i.getTitle() for i in
+                                        current_predecessor_list]
+
+      # If there are items to remove
+      if list(set(current_predecessor_title_list).difference(instance_reference_list)) != []:
+        predecessor_list = [instance.getRelativeUrl() for instance in
+                            current_predecessor_list if instance.getTitle()
+                            in instance_reference_list]
+
+        LOG('SlapTool', INFO, '%s, %s: Updating predecessor list to %s' % (
+          computer_id, computer_partition_id, predecessor_list), error=False)
+        software_instance_document.edit(predecessor_list=predecessor_list,
+            comment='predecessor_list edited to unlink non commited instances')
+      self._storeLastData(cache_reference, instance_reference_xml)
+
   ####################################################
   # Internals methods
   ####################################################

slapos/grid/slapgrid.py

@@ -50,6 +50,7 @@ from lxml import etree
 
 from slapos.slap.slap import NotFoundError
 from slapos.slap.slap import ServerError
+from slapos.slap.slap import COMPUTER_PARTITION_REQUEST_LIST_TEMPLATE_FILENAME
 from slapos.util import mkdir_p, chownDirectory, string_to_boolean
 from slapos.grid.exception import BuildoutFailedError
 from slapos.grid.SlapObject import Software, Partition
@@ -666,6 +667,19 @@ stderr_logfile_backups=1
     if not promise_present:
       self.logger.info("No promise.")
 
+  def _endInstallationTransaction(self, computer_partition):
+    partition_id = computer_partition.getId()
+    transaction_file_name = COMPUTER_PARTITION_REQUEST_LIST_TEMPLATE_FILENAME % partition_id
+    transaction_file_path = os.path.join(self.instance_root,
+                                      partition_id,
+                                      transaction_file_name)
+
+    if os.path.exists(transaction_file_path):
+      with open(transaction_file_path, 'r') as tf:
+      computer_partition.setComputerPartitionRelatedInstanceList(
+        [reference for reference in tf.read().split('\n') if reference]
+      )
+
   def _addFirewallRule(self, rule_command):
     """
     """
@@ -904,6 +918,14 @@ stderr_logfile_backups=1
     self.logger.debug('Check if %s requires processing...' % computer_partition_id)
 
     instance_path = os.path.join(self.instance_root, computer_partition_id)
+    os.environ['SLAPGRID_INSTANCE_ROOT'] = self.instance_root
+
+    # Check if transaction file of this partition exists, if the file was created,
+    # remove it so it will be generate with this new transaction
+    transaction_file_name = COMPUTER_PARTITION_REQUEST_LIST_TEMPLATE_FILENAME % computer_partition_id
+    transaction_file_path = os.path.join(instance_path, transaction_file_name)
+    if os.path.exists(transaction_file_path):
+      os.unlink(transaction_file_path)
 
     # Try to get partition timestamp (last modification date)
     timestamp_path = os.path.join(
@@ -1027,6 +1049,7 @@ stderr_logfile_backups=1
         local_partition.install()
         computer_partition.available()
         local_partition.start()
+        self._endInstallationTransaction(computer_partition)
         if self.firewall_conf:
           self._setupComputerPartitionFirewall(computer_partition,
                                               partition_ip_list)

slapos/slap/interface/slap.py

@@ -337,6 +337,14 @@ class IComputerPartition(IBuildoutController, IRequester):
     computer partition.
     """
 
+  def updateComputerPartitionRelatedInstanceList(instance_reference_list):
+    """
+    Set relation between this Instance and all his children.
+
+    instance_reference_list -- list of instances requested by this Computer
+                               Partition.   
+    """
+
 class IComputer(Interface):
   """
   Computer interface specification

slapos/slap/slap.py

@@ -36,6 +36,7 @@ __all__ = ["slap", "ComputerPartition", "Computer", "SoftwareRelease",
            "Supply", "OpenOrder", "NotFoundError",
            "ResourceNotReady", "ServerError", "ConnectionError"]
 
+import os
 import json
 import logging
 import re
@@ -66,6 +67,7 @@ fallback_logger.addHandler(fallback_handler)
 
 
 DEFAULT_SOFTWARE_TYPE = 'RootSoftwareInstance'
+COMPUTER_PARTITION_REQUEST_LIST_TEMPLATE_FILENAME = '.slapos-request-transaction-%s'
 
 class SlapDocument:
   def __init__(self, connection_helper=None, hateoas_navigator=None):
@@ -80,6 +82,7 @@ class SlapRequester(SlapDocument):
   """
   Abstract class that allow to factor method for subclasses that use "request()"
   """
+
   def _requestComputerPartition(self, request_dict):
     try:
       xml = self._connection_helper.POST('requestComputerPartition', data=request_dict)
@@ -405,9 +408,38 @@ class ComputerPartition(SlapRequester):
     self._partition_id = partition_id
     self._request_dict = request_dict
 
+    # Just create an empty file (for nothing requested yet)
+    self._updateTransactionFile(partition_reference=None)
+
   def __getinitargs__(self):
     return (self._computer_id, self._partition_id, )
 
+  def _updateTransactionFile(self, partition_reference=None):
+    """
+    Store reference to all Instances requested by this Computer Parition
+    """
+    # Environ variable set by Slapgrid while processing this partition
+    instance_root = os.environ.get('SLAPGRID_INSTANCE_ROOT', '')
+    if not instance_root or not self._partition_id:
+      return
+
+    transaction_file_name = COMPUTER_PARTITION_REQUEST_LIST_TEMPLATE_FILENAME % self._partition_id
+    transaction_file_path = os.path.join(instance_root, self._partition_id,
+                                        transaction_file_name)
+
+    try:
+      if partition_reference is None:
+        if os.access(os.path.join(instance_root, self._partition_id), os.W_OK):
+          if os.path.exists(transaction_file_path):
+            return
+          transac_file = open(transaction_file_path, 'w')
+          transac_file.close()
+      else:
+        with open(transaction_file_path, 'a') as transac_file:
+          transac_file.write('%s\n' % partition_reference)
+    except OSError:
+      return
+
   def request(self, software_release, software_type, partition_reference,
               shared=False, partition_parameter_kw=None, filter_kw=None,
               state=None):
@@ -439,6 +471,7 @@ class ComputerPartition(SlapRequester):
         'filter_xml': xml_marshaller.dumps(filter_kw),
         'state': xml_marshaller.dumps(state),
     }
+    self._updateTransactionFile(partition_reference)
     return self._requestComputerPartition(request_dict)
 
   def building(self):
@@ -616,6 +649,15 @@ class ComputerPartition(SlapRequester):
             )
     return xml_marshaller.loads(xml)
 
+  def setComputerPartitionRelatedInstanceList(self, instance_reference_list):
+    self._connection_helper.POST('updateComputerPartitionRelatedInstanceList',
+        data={
+          'computer_id': self._computer_id,
+          'computer_partition_id': self._partition_id,
+          'instance_reference_xml': xml_marshaller.dumps(instance_reference_list)
+          }
+        )
+
 def _addIpv6Brackets(url):
   # if master_url contains an ipv6 without bracket, add it
   # Note that this is mostly to limit specific issues with

slapos/tests/slap.py

@@ -29,6 +29,7 @@ import logging
 import os
 import unittest
 import urlparse
+import tempfile
 
 import httmock
 
@@ -53,6 +54,8 @@ class SlapMixin(unittest.TestCase):
     print 'Testing against SLAP server %r' % self.server_url
     self.slap = slapos.slap.slap()
     self.partition_id = 'PARTITION_01'
+    if os.environ.has_key('SLAPGRID_INSTANCE_ROOT'):
+      del os.environ['SLAPGRID_INSTANCE_ROOT']
 
   def tearDown(self):
     pass
@@ -786,6 +789,85 @@ class TestComputerPartition(SlapMixin):
       # request was done works correctly
       self.assertEqual(requested_partition_id, requested_partition.getId())
 
+  def test_request_with_slapgrid_request_transaction(self):
+    from slapos.slap.slap import COMPUTER_PARTITION_REQUEST_LIST_TEMPLATE_FILENAME
+    partition_id = 'PARTITION_01'
+    instance_root = tempfile.mkdtemp()
+    partition_root = os.path.join(instance_root, partition_id)
+    os.mkdir(partition_root)
+    os.environ['SLAPGRID_INSTANCE_ROOT'] = instance_root
+    transaction_file_name = COMPUTER_PARTITION_REQUEST_LIST_TEMPLATE_FILENAME % partition_id
+    transaction_file_path = os.path.join(partition_root, transaction_file_name)
+
+    def handler(url, req):
+      qs = urlparse.parse_qs(url.query)
+      if (url.path == '/registerComputerPartition'
+              and 'computer_reference' in qs
+              and 'computer_partition_reference' in qs):
+        slap_partition = slapos.slap.ComputerPartition(
+            qs['computer_reference'][0],
+            qs['computer_partition_reference'][0])
+        return {
+                'status_code': 200,
+                'content': xml_marshaller.xml_marshaller.dumps(slap_partition)
+                }
+      elif (url.path == '/getComputerInformation'
+              and 'computer_id' in qs):
+        slap_computer = slapos.slap.Computer(qs['computer_id'][0])
+        slap_computer._software_release_list = []
+        slap_partition = slapos.slap.ComputerPartition(
+            qs['computer_id'][0],
+            partition_id)
+        slap_computer._computer_partition_list = [slap_partition]
+        return {
+                'status_code': 200,
+                'content': xml_marshaller.xml_marshaller.dumps(slap_computer)
+                }
+      elif url.path == '/requestComputerPartition':
+        raise RequestWasCalled
+      else:
+        return {
+                'status_code': 404
+                }
+
+    with httmock.HTTMock(handler):
+      self.computer_guid = self._getTestComputerId()
+      self.slap = slapos.slap.slap()
+      self.slap.initializeConnection(self.server_url)
+      computer_partition = self.slap.registerComputerPartition(
+          self.computer_guid, partition_id)
+
+      self.assertTrue(os.path.exists(transaction_file_path))
+      with open(transaction_file_path, 'r') as f:
+        content = f.read()
+        self.assertEqual(content, '')
+      self.assertRaises(RequestWasCalled,
+                        computer_partition.request,
+                        'http://server/new/' + self._getTestComputerId(),
+                        'software_type', 'myref')
+      self.assertTrue(os.path.exists(transaction_file_path))
+      with open(transaction_file_path, 'r') as f:
+        content_list = f.read().strip().split('\n')
+        self.assertEqual(content_list[0], ['myref'])
+
+      # Not override
+      computer_partition = self.slap.registerComputerPartition(
+          self.computer_guid, partition_id)
+      self.assertTrue(os.path.exists(transaction_file_path))
+      with open(transaction_file_path, 'r') as f:
+        content = f.read()
+        content_list = f.read().strip().split('\n')
+        self.assertEqual(content_list, ['myref'])
+
+      # Request a second instance
+      self.assertRaises(RequestWasCalled,
+                        computer_partition.request,
+                        'http://server/new/' + self._getTestComputerId(),
+                        'software_type', 'mysecondref')
+      with open(transaction_file_path, 'r') as f:
+        content_list = f.read().strip().split('\n')
+        self.assertEquals(list(set(content_list)), ['myref', 'mysecondref'])
+
   def _test_new_computer_partition_state(self, state):
     """
     Helper method to automate assertions of failing states on new Computer

slapos/tests/slapgrid.py

@@ -107,6 +107,8 @@ class BasicMixin(object):
     self._tempdir = tempfile.mkdtemp()
     self.software_root = os.path.join(self._tempdir, 'software')
     self.instance_root = os.path.join(self._tempdir, 'instance')
+    if os.environ.has_key('SLAPGRID_INSTANCE_ROOT'):
+      del os.environ['SLAPGRID_INSTANCE_ROOT']
     logging.basicConfig(level=logging.DEBUG)
     self.setSlapgrid()
 
@@ -338,6 +340,8 @@ class ComputerForTest(object):
         return {'status_code': 200}
       if url.path == '/softwareInstanceBang':
         return {'status_code': 200}
+      if url.path == "/updateComputerPartitionRelatedInstanceList":
+        return {'status_code': 200}
       if url.path == '/softwareInstanceError':
         instance.error_log = '\n'.join(
             [
@@ -1645,16 +1649,21 @@ class TestSlapgridUsageReport(MasterMixin, unittest.TestCase):
       # Then run usage report and see if it is still working
       computer.sequence = []
       self.assertEqual(self.grid.agregateAndSendUsage(), slapgrid.SLAPGRID_SUCCESS)
+      # registerComputerPartition will create one more file: 
+      from slapos.slap.slap import COMPUTER_PARTITION_REQUEST_LIST_TEMPLATE_FILENAME
+      request_list_file = COMPUTER_PARTITION_REQUEST_LIST_TEMPLATE_FILENAME % instance.name
       self.assertInstanceDirectoryListEqual(['0'])
       self.assertItemsEqual(os.listdir(instance.partition_path),
                             ['.slapgrid', '.0_wrapper.log', 'buildout.cfg',
-                             'etc', 'software_release', 'worked', '.slapos-retention-lock-delay'])
+                             'etc', 'software_release', 'worked',
+                             '.slapos-retention-lock-delay', request_list_file])
       wrapper_log = os.path.join(instance.partition_path, '.0_wrapper.log')
       self.assertLogContent(wrapper_log, 'Working')
       self.assertInstanceDirectoryListEqual(['0'])
       self.assertItemsEqual(os.listdir(instance.partition_path),
                             ['.slapgrid', '.0_wrapper.log', 'buildout.cfg',
-                             'etc', 'software_release', 'worked', '.slapos-retention-lock-delay'])
+                             'etc', 'software_release', 'worked',
+                             '.slapos-retention-lock-delay', request_list_file])
       wrapper_log = os.path.join(instance.partition_path, '.0_wrapper.log')
       self.assertLogContent(wrapper_log, 'Working')
       self.assertEqual(computer.sequence,
@@ -2311,3 +2320,20 @@ class TestSlapgridCPWithFirewall(MasterMixin, unittest.TestCase):
         rules_list = json.loads(frules.read())
       self.checkRuleFromIpSource(ip, [source_ip[1]], rules_list)
 
+class TestSlapgridCPWithTransaction(MasterMixin, unittest.TestCase):
+
+from slapos.slap.slap import COMPUTER_PARTITION_REQUEST_LIST_TEMPLATE_FILENAME
+
+  def test_one_partition(self):
+    computer = ComputerForTest(self.software_root, self.instance_root)
+    with httmock.HTTMock(computer.request_handler):
+      instance = computer.instance_list[0]
+      partition = os.path.join(self.instance_root, '0')
+      request_list_file = os.path.join(partition,
+          COMPUTER_PARTITION_REQUEST_LIST_TEMPLATE_FILENAME % instance.name
+      with open(request_list_file, 'w') as f:
+        f.write('some partition')
+      self.assertEqual(self.grid.processComputerPartitionList(), slapgrid.SLAPGRID_SUCCESS)
+      self.assertInstanceDirectoryListEqual(['0'])
+
+      self.assertFalse(os.path.exists(request_list_file)