Raise appropriate exceptions for condition failures (pynamodb#1076)

koreno · Oct 25, 2023 · 93ef963 · 93ef963
1 parent c1d6222
commit 93ef963
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Showing 2 changed files with 22 additions and 2 deletions.
diff --git a/pynamodb/connection/base.py b/pynamodb/connection/base.py
@@ -1048,7 +1048,10 @@ def update_item(
         try:
             return self.dispatch(UPDATE_ITEM, operation_kwargs, settings)
         except BOTOCORE_EXCEPTIONS as e:
-            raise UpdateError("Failed to update item: {}".format(e), e)
+            exc = UpdateError("Failed to update item: {}".format(e), e)
+            if exc.cause_response_code == "ConditionalCheckFailedException":
+                exc.__class__ = ConditionFailedUpdate
+            raise exc
 
     def put_item(
         self,
@@ -1079,7 +1082,10 @@ def put_item(
         try:
             return self.dispatch(PUT_ITEM, operation_kwargs, settings)
         except BOTOCORE_EXCEPTIONS as e:
-            raise PutError("Failed to put item: {}".format(e), e)
+            exc = PutError("Failed to put item: {}".format(e), e)
+            if exc.cause_response_code == "ConditionalCheckFailedException":
+                exc.__class__ = ConditionFailedPut
+            raise exc
 
     def _get_transact_operation_kwargs(
         self,

diff --git a/pynamodb/exceptions.py b/pynamodb/exceptions.py
@@ -84,13 +84,27 @@ class PutError(PynamoDBConnectionError):
     msg = "Error putting item"
 
 
+class ConditionFailedPut(PutError):
+    """
+    Raised when an item fails to be created due to condition
+    """
+    msg = "Condition failed while putting item"
+
+
 class UpdateError(PynamoDBConnectionError):
     """
     Raised when an item fails to be updated
     """
     msg = "Error updating item"
 
 
+class ConditionFailedUpdate(UpdateError):
+    """
+    Raised when an item fails to be updated due to condition
+    """
+    msg = "Condition failed while updating item"
+
+
 class GetError(PynamoDBConnectionError):
     """
     Raised when an item fails to be retrieved