[fix] Handle Sequence metadata inconsistency (#2562)

CHANGELOG.md

@@ -2,6 +2,7 @@
 
 ## 3.16.2
 - Expose `capture_terminal_logs` argument for `aim.sdk.adapters` classes (mihran113)
+- Handle inconsistency between Sequence data and metadata (alberttorosyan) 
 
 ## 3.16.1
 

aim/sdk/sequence.py

@@ -190,7 +190,7 @@ def numpy(self) -> Tuple[np.ndarray, List[np.ndarray]]:
             steps = np.fromiter(self.steps.values(), np.intp)
             columns = [np.fromiter(arr.values(), arr.dtype) for arr in self.arrays]
         else:
-            last_step = self.meta_tree['last_step']
+            last_step = self.meta_tree.get('last_step', None)
             steps = np.fromiter(islice(self.steps.values(), self.n_items), np.intp)
             columns = [np.fromiter(islice(arr.values(), self.n_items), arr.dtype) for arr in self.arrays]
 
@@ -344,14 +344,15 @@ def first_step(self):
 
         Required to implement ranged and sliced data fetching.
         """
-        return self._meta_tree['first_step']
+        return self._meta_tree.get('first_step', 0)
 
     def last_step(self):
         """Get sequence tracked last step.
 
         Required to implement ranged and sliced data fetching.
         """
-        return self._meta_tree['last_step']
+        # fallback to first_step() if 'last_step' key is not yet written
+        return self._meta_tree.get('last_step', self.first_step())
 
 
 class MediaSequenceBase(Sequence):

aim/sdk/sequences/distribution_sequence.py

@@ -14,17 +14,3 @@ def allowed_dtypes(cls) -> Tuple[str, ...]:
     @classmethod
     def sequence_name(cls) -> str:
         return 'distributions'
-
-    def first_step(self):
-        """Get sequence tracked first step.
-
-        Required to implement ranged and sliced data fetching.
-        """
-        return self._meta_tree['first_step']
-
-    def last_step(self):
-        """Get sequence tracked last step.
-
-        Required to implement ranged and sliced data fetching.
-        """
-        return self._meta_tree['last_step']

aim/sdk/sequences/figure_sequence.py

@@ -14,17 +14,3 @@ def allowed_dtypes(cls) -> Union[str, Tuple[str, ...]]:
     @classmethod
     def sequence_name(cls) -> str:
         return "figures"
-
-    def first_step(self):
-        """Get sequence tracked first step.
-
-        Required to implement ranged and sliced data fetching.
-        """
-        return self._meta_tree["first_step"]
-
-    def last_step(self):
-        """Get sequence tracked last step.
-
-        Required to implement ranged and sliced data fetching.
-        """
-        return self._meta_tree["last_step"]