Allow atoms to save their own state/result

Instead of having storage adjust the internals of
the atom detail types (which requires type checking),
remove the type checking and let the types themselves
decide where to put their own states and results.

Change-Id: I397954dc746e9dacb2b65e352d11d8f7f36cdac4

taskflow/persistence/logbook.py

@@ -49,6 +49,10 @@ def _safe_unmarshal_time(when):
     return timeutils.unmarshall_time(when)
 
 
+def _was_failure(state, result):
+    return state == states.FAILURE and isinstance(result, misc.Failure)
+
+
 def _fix_meta(data):
     # Handle the case where older schemas allowed this to be non-dict by
     # correcting this case by replacing it with a dictionary when a non-dict
@@ -317,6 +321,10 @@ class AtomDetail(object):
     def to_dict(self):
         """Translates the internal state of this object to a dictionary."""
 
+    @abc.abstractmethod
+    def put(self, state, result):
+        """Puts a result (acquired in the given state) into this detail."""
+
     def _to_dict_shared(self):
         if self.failure:
             failure = self.failure.to_dict()
@@ -367,6 +375,15 @@ class TaskDetail(AtomDetail):
         self.state = state
         self.intention = states.EXECUTE
 
+    def put(self, state, result):
+        self.state = state
+        if _was_failure(state, result):
+            self.failure = result
+            self.results = None
+        else:
+            self.results = result
+            self.failure = None
+
     @classmethod
     def from_dict(cls, data):
         """Translates the given data into an instance of this class."""
@@ -416,6 +433,15 @@ class RetryDetail(AtomDetail):
         except IndexError as e:
             raise exc.NotFound("Last failures not found", e)
 
+    def put(self, state, result):
+        # Do not clean retry history (only on reset does this happen).
+        self.state = state
+        if _was_failure(state, result):
+            self.failure = result
+        else:
+            self.results.append((result, {}))
+            self.failure = None
+
     @classmethod
     def from_dict(cls, data):
         """Translates the given data into an instance of this class."""

taskflow/storage.py

@@ -53,7 +53,7 @@ class Storage(object):
         self._lock = self._lock_cls()
 
         # NOTE(imelnikov): failure serialization looses information,
-        # so we cache failures here, in task name -> misc.Failure mapping.
+        # so we cache failures here, in atom name -> failure mapping.
         self._failures = {}
         for ad in self._flowdetail:
             if ad.failure is not None:
@@ -322,24 +322,12 @@ class Storage(object):
         """Put result for atom with id 'uuid' to storage."""
         with self._lock.write_lock():
             ad = self._atomdetail_by_name(atom_name)
-            ad.state = state
+            ad.put(state, data)
             if state == states.FAILURE and isinstance(data, misc.Failure):
-                # FIXME(harlowja): this seems like it should be internal logic
-                # in the atom detail object and not in here. Fix that soon...
-                #
-                # Do not clean retry history
-                if not isinstance(ad, logbook.RetryDetail):
-                    ad.results = None
-                ad.failure = data
+                # NOTE(imelnikov): failure serialization looses information,
+                # so we cache failures here, in atom name -> failure mapping.
                 self._failures[ad.name] = data
             else:
-                # FIXME(harlowja): this seems like it should be internal logic
-                # in the atom detail object and not in here. Fix that soon...
-                if isinstance(ad, logbook.RetryDetail):
-                    ad.results.append((data, {}))
-                else:
-                    ad.results = data
-                ad.failure = None
                 self._check_all_results_provided(ad.name, data)
             self._with_connection(self._save_atom_detail, ad)