If match headers (Azure#13315)

* verifying match conditions are correct, adding tests for other conditions

* changes to verify etag is working, think it's being ignored by service

* another change to test file, passing the correct etag to the service, it returns a 204 so no error is produced

* renaming vars

* testing for if-match conditions to make sure they are properly parsed and sent to service

* reverting header back

* testing update to reflect new response in create_entity

sdk/tables/azure-data-tables/azure/data/tables/_serialize.py

@@ -42,6 +42,8 @@ def _get_match_headers(kwargs, match_param, etag_param):
             raise ValueError("'{}' specified without '{}'.".format(match_param, etag_param))
     elif match_condition == MatchConditions.IfMissing:
         if_none_match = '*'
+    elif match_condition == MatchConditions.Unconditionally:
+        if_none_match = '*'
     elif match_condition is None:
         if kwargs.get(etag_param):
             raise ValueError("'{}' specified without '{}'.".format(etag_param, match_param))

sdk/tables/azure-data-tables/azure/data/tables/_table_client.py

@@ -239,6 +239,7 @@ def delete_entity(
         if_match, _ = _get_match_headers(kwargs=dict(kwargs, etag=kwargs.pop('etag', None),
                                                                 match_condition=kwargs.pop('match_condition', None)),
                                                     etag_param='etag', match_param='match_condition')
+
         try:
             self._client.table.delete_entity(
                 table=self.table_name,

sdk/tables/azure-data-tables/tests/recordings/test_table_entity.test_get_entity_if_match.yaml

@@ -191,6 +191,49 @@ interactions:
     status:
       code: 204
       message: No Content
+- request:
+    body: null
+    headers:
+      Accept:
+      - application/json;odata=minimalmetadata
+      Accept-Encoding:
+      - gzip, deflate
+      Connection:
+      - keep-alive
+      DataServiceVersion:
+      - '3.0'
+      Date:
+      - Tue, 25 Aug 2020 15:09:34 GMT
+      User-Agent:
+      - azsdk-python-data-tables/2019-07-07 Python/3.8.4 (Windows-10-10.0.19041-SP0)
+      x-ms-date:
+      - Tue, 25 Aug 2020 15:09:34 GMT
+      x-ms-version:
+      - '2019-07-07'
+    method: GET
+    uri: https://storagename.table.core.windows.net/uttable74691147(PartitionKey='pk74691147',RowKey='rk74691147')
+  response:
+    body:
+      string: '{"odata.error":{"code":"ResourceNotFound","message":{"lang":"en-US","value":"The
+        specified resource does not exist.\nRequestId:32d896fc-f002-0081-26f1-7abf70000000\nTime:2020-08-25T15:09:35.2385928Z"}}}'
+    headers:
+      cache-control:
+      - no-cache
+      content-type:
+      - application/json;odata=minimalmetadata;streaming=true;charset=utf-8
+      date:
+      - Tue, 25 Aug 2020 15:09:34 GMT
+      server:
+      - Windows-Azure-Table/1.0 Microsoft-HTTPAPI/2.0
+      transfer-encoding:
+      - chunked
+      x-content-type-options:
+      - nosniff
+      x-ms-version:
+      - '2019-07-07'
+    status:
+      code: 404
+      message: Not Found
 - request:
     body: null
     headers: