Append with Flush (#19298)

* Append with Flush (#18546)

* PR comment

Author: seanmcc-msft

specification/storage/data-plane/Azure.Storage.Files.DataLake/preview/2021-06-08/DataLakeStorage.json

@@ -2196,6 +2196,9 @@
           },
           {
             "$ref": "#/parameters/EncryptionAlgorithm"
+          },
+          {
+            "$ref": "#/parameters/Flush"
           }
         ],
         "responses": {
@@ -3165,6 +3168,14 @@
         "name": "cpk-info"
       },
       "description": "The algorithm used to produce the encryption key hash. Currently, the only accepted value is \"AES256\". Must be provided if the x-ms-encryption-key header is provided."
+    },
+    "Flush": {
+      "name": "flush",
+      "type": "boolean",
+      "in": "query",
+      "required": false,
+      "x-ms-parameter-location": "method",
+      "description": "If file should be flushed after the append"
     }
   },
   "definitions": {