slapgrid.promise: Improve promise check speed

Use cache to  save some promise instance information.
First run of slapgrid fill each promise cached (when there is no cache). The next run will check some usefull info like if promise `is test less` or promise `is anomaly less` directly from cache without need to import the module.

Cache is updated if promise file or module change, or if the promise periodicity expire (when the promise it update cache).

/reviewed-on !101

slapos/grid/promise/__init__.py

@@ -37,6 +37,7 @@ import json
 import importlib
 import traceback
 import psutil
+import inspect
 from multiprocessing import Process, Queue as MQueue
 from six.moves import queue, reload_module
 from slapos.util import mkdir_p, chownDirectory
@@ -46,11 +47,12 @@ from slapos.grid.promise.generic import (GenericPromise, PromiseQueueResult,
                                          AnomalyResult, TestResult,
                                          PROMISE_STATE_FOLDER_NAME,
                                          PROMISE_RESULT_FOLDER_NAME,
-                                         PROMISE_PARAMETER_NAME,
-                                         PROMISE_PERIOD_FILE_NAME)
+                                         PROMISE_PARAMETER_NAME)
 from slapos.grid.promise.wrapper import WrapPromise
 from slapos.version import version
 
+PROMISE_CACHE_FOLDER_NAME = '.slapgrid/promise/cache'
+
 class PromiseError(Exception):
   pass
 
@@ -69,6 +71,7 @@ class PromiseProcess(Process):
       @param promise_name: The name of the promise to run
       @param promise_path: path of the promise
       @param argument_dict: all promise parameters in a dictionary
+      @param queue: Queue used to send promise result
       @param allow_bang: Bolean saying if bang should be called in case of
         anomaly failure.
       @param check_anomaly: Bolean saying if promise anomaly should be run.
@@ -89,54 +92,66 @@ class PromiseProcess(Process):
     self.partition_folder = partition_folder
     self.wrap_promise = wrap
     self._periodicity = None
-    self._timestamp_file = os.path.join(partition_folder,
-                                        PROMISE_STATE_FOLDER_NAME,
-                                        '%s.timestamp' % promise_name)
-    periodicity_file = os.path.join(partition_folder,
+    self.cache_folder = os.path.join(self.partition_folder,
+                                     PROMISE_CACHE_FOLDER_NAME)
+    self.cache_file = os.path.join(self.cache_folder, self.getPromiseTitle())
+    # XXX - remove old files used to store promise timestamp and periodicity
+    self._cleanupDeprecated()
+
+  def _cleanupDeprecated(self):
+    timestamp_file = os.path.join(self.partition_folder,
+                                  PROMISE_STATE_FOLDER_NAME,
+                                  '%s.timestamp' % self.name)
+    periodicity_file = os.path.join(self.partition_folder,
                                     PROMISE_STATE_FOLDER_NAME,
-                                    PROMISE_PERIOD_FILE_NAME % promise_name)
-    if os.path.exists(periodicity_file) and os.stat(periodicity_file).st_size:
-      with open(periodicity_file) as f:
-        try:
-          self._periodicity = float(f.read())
-        except ValueError:
-          # set to None, run the promise and regenerate the file
-          pass
+                                    '%s.periodicity' % self.name)
+    if os.path.exists(timestamp_file) and os.path.isfile(timestamp_file):
+      os.unlink(timestamp_file)
+    if os.path.exists(periodicity_file) and os.path.isfile(periodicity_file):
+      os.unlink(periodicity_file)
+
+  def getPromiseTitle(self):
+    return os.path.splitext(self.name)[0]
 
-  def isPeriodicityMatch(self):
+  def updatePromiseCache(self, promise_class, promise_instance, started=True):
     """
-      Return True if promise should be run now, considering the promise
-        periodicity in minutes
+      Cache some data from the promise that can be reused
     """
-    if self._periodicity is not None and \
-        os.path.exists(self._timestamp_file) and \
-        os.stat(self._timestamp_file).st_size:
-      with open(self._timestamp_file) as f:
-        try:
-          latest_timestamp = float(f.read())
-          current_timediff = (time.time() - latest_timestamp) / 60.0
-          if current_timediff >= self._periodicity:
-            return True
-          #self.logger.debug("Skip Promise %r. periodicity=%s, time_diff=%s" % (
-          #    self.name, self._periodicity, current_timediff))
-        except ValueError:
-          # if the file is broken, run the promise and regenerate it
-          return True
-        else:
-          return False
-    return True
+    py_file = '%s.py' % os.path.splitext(inspect.getfile(promise_class))[0]
+    stat = os.stat(py_file)
+    timestamp = time.time()
+    cache_dict = dict(
+      is_tested= not hasattr(promise_instance, 'isTested') or \
+          promise_instance.isTested(),
+      is_anomaly_detected=not hasattr(promise_instance, 'isAnomalyDetected') or \
+          promise_instance.isAnomalyDetected(),
+      periodicity=promise_instance.getPeriodicity(),
+      next_run_after=timestamp + (promise_instance.getPeriodicity() * 60.0),
+      timestamp=timestamp,
+      module_file=py_file,
+      module_file_mtime=stat.st_mtime,
+    )
+    if not started:
+      cache_dict['next_run_after'] = timestamp
+    with open(self.cache_file, 'w') as f:
+      f.write(json.dumps(cache_dict))
 
-  def setPromiseStartTimestamp(self):
+  def loadPromiseCacheDict(self):
     """
-      Save the promise execution timestamp
+      Load cached data for this promise.
+      If saved promise module file is not exists then invalidate cache.
+      Cache will be updated when promise run
     """
-    state_directory = os.path.dirname(self._timestamp_file)
-    mkdir_p(state_directory)
-    with open(self._timestamp_file, 'w') as f:
-      f.write(str(time.time()))
-
-  def getPromiseTitle(self):
-    return os.path.splitext(self.name)[0]
+    if os.path.exists(self.cache_file):
+      try:
+        with open(self.cache_file) as f:
+          cache_dict = json.loads(f.read())
+          if not os.path.exists(cache_dict['module_file']):
+            # file not exists mean path was changed
+            return None
+          return cache_dict
+      except ValueError:
+        return None
 
   def run(self):
     """
@@ -146,9 +161,10 @@ class PromiseProcess(Process):
     """
     try:
       os.chdir(self.partition_folder)
+      promise_started = False
       if self.uid and self.gid:
         dropPrivileges(self.uid, self.gid, logger=self.logger)
-
+      mkdir_p(self.cache_folder)
       if self.wrap_promise:
         promise_instance = WrapPromise(self.argument_dict)
       else:
@@ -161,7 +177,11 @@ class PromiseProcess(Process):
           (promise_instance.isAnomalyDetected() and self.check_anomaly) or \
           (promise_instance.isTested() and not self.check_anomaly):
         # if the promise will run, we save execution timestamp
-        self.setPromiseStartTimestamp()
+        promise_started = True
+      self.updatePromiseCache(
+        WrapPromise if self.wrap_promise else promise_module.RunPromise,
+        promise_instance,
+        started=promise_started)
       promise_instance.run(self.check_anomaly, self.allow_bang)
     except Exception:
       self.logger.error(traceback.format_exc())
@@ -218,6 +238,7 @@ class PromiseProcess(Process):
                            key, extra_dict))
         self.argument_dict[key] = extra_dict[key]
 
+
 class PromiseLauncher(object):
 
   def __init__(self, config=None, logger=None, dry_run=False):
@@ -311,6 +332,7 @@ class PromiseLauncher(object):
 
     self.queue_result = MQueue()
     self.bang_called = False
+    self._skipped_amount = 0
 
     self.promise_output_dir = os.path.join(
       self.partition_folder,
@@ -375,6 +397,19 @@ class PromiseLauncher(object):
           ))
     return result
 
+  def _writePromiseResult(self, result_item):
+    if result_item.item.type() == "Empty Result":
+      # no result collected (sense skipped)
+      return
+    elif result_item.item.hasFailed():
+      self.logger.error(result_item.item.message)
+      if result_item.execution_time != -1 and \
+          isinstance(result_item.item, AnomalyResult) and self.check_anomaly:
+        # stop to bang as it was called
+        self.bang_called = True
+    # Send result
+    self._savePromiseResult(result_item)
+
   def _emptyQueue(self):
     """Remove all entries from queue until it's empty"""
     while True:
@@ -390,6 +425,11 @@ class PromiseLauncher(object):
                                  PROMISE_STATE_FOLDER_NAME)
     chownDirectory(folder_path, stat_info.st_uid, stat_info.st_gid)
 
+  def isPeriodicityMatch(self, next_timestamp):
+    if next_timestamp:
+      return time.time() >= next_timestamp
+    return True
+
   def _launchPromise(self, promise_name, promise_path, argument_dict,
       wrap_process=False):
     """
@@ -399,7 +439,6 @@ class PromiseLauncher(object):
       If the promise periodicity doesn't match, the previous promise result is
       checked.
     """
-    self.logger.info("Checking promise %s..." % promise_name)
     try:
       promise_process = PromiseProcess(
         self.partition_folder,
@@ -414,8 +453,18 @@ class PromiseLauncher(object):
         wrap=wrap_process,
       )
 
-      if not self.force and not promise_process.isPeriodicityMatch():
+      promise_cache_dict = promise_process.loadPromiseCacheDict()
+      if promise_cache_dict is not None:
+        if self.check_anomaly and not promise_cache_dict.get('is_anomaly_detected') \
+            or not self.check_anomaly and not promise_cache_dict.get('is_tested'):
+          # promise is skipped, send empty result
+          self._writePromiseResult(PromiseQueueResult())
+          self._skipped_amount += 1
+          return
+      if not self.force and (promise_cache_dict is not None and not
+          self.isPeriodicityMatch(promise_cache_dict.get('next_run_after'))):
         # we won't start the promise process, just get the latest result
+        self._skipped_amount += 1
         result = self._loadPromiseResult(promise_process.getPromiseTitle())
         if result is not None:
           if result.item.hasFailed():
@@ -432,6 +481,7 @@ class PromiseLauncher(object):
       self.logger.warning("Promise %s skipped." % promise_name)
       return True
 
+    self.logger.info("Checking promise %s..." % promise_name)
     queue_item = None
     sleep_time = 0.1
     increment_limit = int(self.promise_timeout / sleep_time)
@@ -498,21 +548,8 @@ class PromiseLauncher(object):
         message="Error: No output returned by the promise",
         execution_time=execution_time
       )
-    elif queue_item.item.type() == "Empty Result":
-      # no result collected (sense skipped)
-      skipped_method = "Anomaly" if self.check_anomaly else "Test"
-      self.logger.debug("Skipped, %s is disabled in promise %r." % (
-        skipped_method, promise_name))
-      return False
-
-    if not self.dry_run:
-      self._savePromiseResult(queue_item)
-    if queue_item.item.hasFailed():
-      self.logger.error(queue_item.item.message)
-      if isinstance(queue_item.item, AnomalyResult) and self.check_anomaly:
-        # stop to bang as it was called
-        self.bang_called = True
 
+    self._writePromiseResult(queue_item)
     if self.debug:
       self.logger.debug("Finished promise %r in %s second(s)." % (
                        promise_name, execution_time))
@@ -584,6 +621,8 @@ class PromiseLauncher(object):
           failed_promise_name = promise_name
 
     self._updateFolderOwner(self.promise_output_dir)
-
+    if self._skipped_amount > 0:
+      self.logger.info("%s promises didn't need to be checked." % \
+        self._skipped_amount)
     if failed_promise_name:
       raise PromiseError("Promise %r failed." % failed_promise_name)

slapos/grid/promise/generic.py

@@ -46,7 +46,6 @@ PROMISE_RESULT_FOLDER_NAME = '.slapgrid/promise/result'
 PROMISE_LOG_FOLDER_NAME = '.slapgrid/promise/log'
 
 PROMISE_PARAMETER_NAME = 'extra_config_dict'
-PROMISE_PERIOD_FILE_NAME = '%s.periodicity'
 
 LOGLINE_RE = r"(\d{4}-\d{2}-\d{2}\s+\d{2}:\d{2}:\d{2})\s+\-?\s*(\w{4,7})\s+\-?\s+(\d+\-\d{3})\s+\-?\s*(.*)"
 matchLogStr = re.compile(LOGLINE_RE).match
@@ -159,10 +158,6 @@ class GenericPromise(with_metaclass(ABCMeta, object)):
     self.__promise_path = self.__config.pop('path', None)
     self.__queue = self.__config.pop('queue', None)
     self.__logger_buffer = None
-    self.__periodicity_file = os.path.join(
-      self.__partition_folder,
-      PROMISE_STATE_FOLDER_NAME,
-      PROMISE_PERIOD_FILE_NAME % self.__name)
     self.setPeriodicity(self.__config.pop('periodicity', 2))
 
     self.__transaction_id = '%s-%s' % (int(time.time()), random.randint(100, 999))
@@ -236,8 +231,6 @@ class GenericPromise(with_metaclass(ABCMeta, object)):
     if minute <= 0:
       raise ValueError("Cannot set promise periodicity to a value less than 1")
     self.__periodicity = minute
-    with open(self.__periodicity_file, 'w') as f:
-      f.write('%s' % minute)
 
   def getPeriodicity(self):
     return self.__periodicity

slapos/tests/test_promise.py

@@ -36,7 +36,8 @@ import logging
 from datetime import datetime, timedelta
 import six
 from six.moves import queue
-from slapos.grid.promise import interface, PromiseLauncher, PromiseProcess, PromiseError
+from slapos.grid.promise import (interface, PromiseLauncher, PromiseProcess,
+                                 PromiseError, PROMISE_CACHE_FOLDER_NAME)
 from slapos.grid.promise.generic import (GenericPromise, TestResult, AnomalyResult,
                                          PromiseQueueResult, PROMISE_STATE_FOLDER_NAME,
                                          PROMISE_RESULT_FOLDER_NAME,
@@ -93,7 +94,7 @@ class TestSlapOSPromiseMixin(unittest.TestCase):
 
     self.launcher = PromiseLauncher(
       config=parameter_dict,
-      logger=logging.getLogger('slapos.test.promise'),
+      #logger=logging.getLogger('slapos.test.promise'),
       dry_run=dry_run
     )
     if save_method:
@@ -1213,6 +1214,102 @@ exit 1
     # no result returned by the promise
     self.assertTrue(self.called)
 
+  def test_promise_cache(self):
+    promise_name = 'my_promise.py'
+    promise_file = os.path.join(self.plugin_dir, promise_name)
+    self.configureLauncher(timeout=1, enable_anomaly=True)
+    self.generatePromiseScript(promise_name, success=True, periodicity=0.01,
+      with_anomaly=True, is_tested=False)
+
+    # run promise, no failure
+    self.launcher.run()
+    cache_folder = os.path.join(self.partition_dir, PROMISE_CACHE_FOLDER_NAME)
+    cache_file = os.path.join(cache_folder, 'my_promise')
+    self.assertTrue(os.path.exists(cache_folder))
+    self.assertTrue(os.path.exists(cache_file))
+    file_stat = os.stat(promise_file)
+    with open(cache_file) as f:
+      cache_dict = json.load(f)
+    timestamp = cache_dict.pop('timestamp')
+    info_dict = {
+      u'is_tested': False,
+      u'is_anomaly_detected': True,
+      u'periodicity': 0.01,
+      u'next_run_after' : (timestamp + 0.01 * 60.0),
+      u'module_file': u'%s' % promise_file,
+      u'module_file_mtime': file_stat.st_mtime,
+    }
+    # next run is in future
+    self.assertTrue(info_dict['next_run_after'] > time.time())
+    self.assertEqual(info_dict, cache_dict)
+
+  def test_promise_cache_expire_with_periodicity(self):
+    self.called = False
+    def test_method(result):
+      self.called = True
+
+    promise_name = 'my_promise.py'
+    promise_file = os.path.join(self.plugin_dir, promise_name)
+    self.configureLauncher(save_method=test_method, timeout=1, enable_anomaly=True)
+    self.generatePromiseScript(promise_name, success=True, periodicity=0.01,
+      with_anomaly=True, is_tested=False)
+
+    # run promise, no failure
+    self.launcher.run()
+    cache_folder = os.path.join(self.partition_dir, PROMISE_CACHE_FOLDER_NAME)
+    cache_file = os.path.join(cache_folder, 'my_promise')
+    self.assertTrue(os.path.exists(cache_folder))
+    self.assertTrue(os.path.exists(cache_file))
+    file_stat = os.stat(promise_file)
+    with open(cache_file) as f:
+      cache_dict = json.load(f)
+    timestamp = cache_dict.pop('timestamp')
+    info_dict = {
+      u'is_tested': False,
+      u'is_anomaly_detected': True,
+      u'periodicity': 0.01,
+      u'next_run_after' : (timestamp + 0.01 * 60.0),
+      u'module_file': u'%s' % promise_file,
+      u'module_file_mtime': file_stat.st_mtime,
+    }
+    self.assertEqual(info_dict, cache_dict)
+    self.assertTrue(self.called)
+    next_run_after = cache_dict['next_run_after']
+
+    # periodicity not match
+    self.called = False
+    self.configureLauncher(save_method=test_method, timeout=1, enable_anomaly=True)
+    self.launcher.run()
+    self.assertFalse(self.called)
+    with open(cache_file) as f:
+      cache_dict = json.load(f)
+    # no change!
+    current_timestamp = cache_dict.pop('timestamp')
+    self.assertEqual(current_timestamp, timestamp)
+    self.assertEqual(info_dict, cache_dict)
+
+    time.sleep(1)
+    # periodicity match
+    self.configureLauncher(save_method=test_method, timeout=1, enable_anomaly=True)
+    self.launcher.run()
+
+    # cached was updated
+    with open(cache_file) as f:
+      cache_dict = json.load(f)
+    new_timestamp = cache_dict.pop('timestamp')
+    info_dict = {
+      u'is_tested': False,
+      u'is_anomaly_detected': True,
+      u'periodicity': 0.01,
+      u'next_run_after' : (new_timestamp + 0.01 * 60.0),
+      u'module_file': u'%s' % promise_file,
+      u'module_file_mtime': file_stat.st_mtime,
+    }
+    self.assertTrue(new_timestamp > timestamp)
+    # next run is in future
+    self.assertTrue(cache_dict['next_run_after'] > next_run_after)
+    self.assertEqual(info_dict, cache_dict)
+
 class TestSlapOSGenericPromise(TestSlapOSPromiseMixin):
 
   def initialisePromise(self, promise_content="", success=True, timeout=60):