Added blob exists method

sdk/storage/azure-storage-blob/azure/storage/blob/_blob_client.py

@@ -18,6 +18,7 @@
 
 import six
 from azure.core.tracing.decorator import distributed_trace
+from azure.core.exceptions import ResourceNotFoundError
 
 from ._shared import encode_base64
 from ._shared.base_client import StorageAccountHostsMixin, parse_connection_str, parse_query
@@ -918,6 +919,31 @@ def undelete_blob(self, **kwargs):
         except StorageErrorException as error:
             process_storage_error(error)
 
+    @distributed_trace()
+    def exists(self, **kwargs):
+        # type: (**Any) -> bool
+        """
+        Returns True if a blob exists with the defined parameters, and returns
+        False otherwise.
+
+        :param str version_id:
+            The version id parameter is an opaque DateTime
+            value that, when present, specifies the version of the blob to check if it exists.
+        :param int timeout:
+            The timeout parameter is expressed in seconds.
+        :returns: boolean
+        """
+        try:
+            blob_props = self._client.blob.get_properties(
+                snapshot=self.snapshot,
+                cls=deserialize_blob_properties,
+                **kwargs)
+            if blob_props and blob_props.is_current_version or blob_props and self.snapshot:
+                return True
+            return False
+        except ResourceNotFoundError:
+            return False
+
     @distributed_trace
     def get_blob_properties(self, **kwargs):
         # type: (**Any) -> BlobProperties

sdk/storage/azure-storage-blob/azure/storage/blob/aio/_blob_client_async.py

@@ -11,6 +11,7 @@
 )
 
 from azure.core.tracing.decorator_async import distributed_trace_async
+from azure.core.exceptions import ResourceNotFoundError
 
 from .._shared.base_client_async import AsyncStorageAccountHostsMixin
 from .._shared.policies_async import ExponentialRetry
@@ -460,6 +461,31 @@ async def undelete_blob(self, **kwargs):
         except StorageErrorException as error:
             process_storage_error(error)
 
+    @distributed_trace_async
+    async def exists(self, **kwargs):
+        # type: (**Any) -> bool
+        """
+        Returns True if a blob exists with the defined parameters, and returns
+        False otherwise.
+
+        :param str version_id:
+            The version id parameter is an opaque DateTime
+            value that, when present, specifies the version of the blob to check if it exists.
+        :param int timeout:
+            The timeout parameter is expressed in seconds.
+        :returns: boolean
+        """
+        try:
+            blob_props = await self._client.blob.get_properties(
+                **kwargs,
+                snapshot=self.snapshot,
+                cls=deserialize_blob_properties)
+            if blob_props and blob_props.is_current_version or blob_props and self.snapshot:
+                return True
+            return False
+        except ResourceNotFoundError:
+            return False
+
     @distributed_trace_async
     async def get_blob_properties(self, **kwargs):
         # type: (Any) -> BlobProperties