wscalls: unflatten payload when calling webservice (#66916)

tests/workflow/test_wscall.py

@@ -594,6 +594,7 @@ def test_webservice_with_unflattened_payload_keys(http_requests, pub):
     item.post_data = {
         'foo/0': 'first',
         'foo/1': 'second',
+        'foo/2': '{{ form_name }}',
         'bar': 'example',
         'form//name': '{{ form_name }}',
     }
@@ -602,7 +603,7 @@ def test_webservice_with_unflattened_payload_keys(http_requests, pub):
     assert http_requests.get_last('url') == 'http://remote.example.net/'
     assert http_requests.get_last('method') == 'POST'
     payload = json.loads(http_requests.get_last('body'))
-    assert payload == {'foo': ['first', 'second'], 'bar': 'example', 'form/name': 'baz'}
+    assert payload == {'foo': ['first', 'second', 'baz'], 'bar': 'example', 'form/name': 'baz'}
     assert http_requests.count() == 1
 
     http_requests.empty()

wcs/wscalls.py

@@ -66,8 +66,6 @@ def unflatten_keys(d):
     if not isinstance(d, dict) or not d:  # unflattening an empty dict has no sense
         return d
 
-    # ok d is a dict
-
     def split_key(key):
         def map_key(x):
             if misc.is_ascii_digit(x):
@@ -234,7 +232,7 @@ def call_webservice(
     if method in ('PATCH', 'PUT', 'POST', 'DELETE') and post_data:
         payload = {}
         with get_publisher().complex_data():
-            for key, value in unflatten_keys(post_data).items():
+            for key, value in post_data.items():
                 try:
                     payload[key] = WorkflowStatusItem.compute(value, allow_complex=True, raises=True)
                 except Exception as e:
@@ -242,6 +240,7 @@ def call_webservice(
                 else:
                     if payload[key]:
                         payload[key] = get_publisher().get_cached_complex_data(payload[key])
+        payload = unflatten_keys(payload)
 
     # if formdata has to be sent, it's the payload. If post_data exists,
     # it's added in formdata['extra']