{AKS} Fix custom header extraction issue

src/azure-cli/azure/cli/command_modules/acs/_validators.py

@@ -416,6 +416,7 @@ def extract_comma_separated_string(
     allow_empty_value=False,
     keep_none=False,
     default_value=None,
+    allow_appending_values_to_same_key=False,
 ):
     """Extract comma-separated string.
 
@@ -425,6 +426,8 @@ def extract_comma_separated_string(
     Option allow_empty_value is valid since extract_kv is specified. When the number of string segments split by "="
     is 1, the first segment is retained as the key and empty string would be set as its corresponding value without
     raising an exception.
+    Option allow_appending_values_to_same_key is valid since extract_kv is specified. For the same key, the new value
+    is appended to the existing value separated by commas.
     If keep_none is specified, will return None when input is None. Otherwise will return default_value if input is
     None or empty string.
     """
@@ -457,6 +460,8 @@ def extract_comma_separated_string(
                 if enable_strip:
                     key = key.strip()
                     value = value.strip()
+                if allow_appending_values_to_same_key and key in result:
+                    value = "{},{}".format(result[key], value)
                 result[key] = value
             else:
                 raise InvalidArgumentValueError(

src/azure-cli/azure/cli/command_modules/acs/agentpool_decorator.py

@@ -349,6 +349,7 @@ def get_aks_custom_headers(self) -> Dict[str, str]:
             enable_strip=True,
             extract_kv=True,
             default_value={},
+            allow_appending_values_to_same_key=True,
         )
 
         # this parameter does not need validation

src/azure-cli/azure/cli/command_modules/acs/custom.py

@@ -3203,6 +3203,7 @@ def aks_agentpool_add(cmd, client, resource_group_name, cluster_name, nodepool_n
         enable_strip=True,
         extract_kv=True,
         default_value={},
+        allow_appending_values_to_same_key=True,
     )
 
     return sdk_no_wait(
@@ -3300,6 +3301,7 @@ def aks_agentpool_upgrade(cmd, client, resource_group_name, cluster_name,
         enable_strip=True,
         extract_kv=True,
         default_value={},
+        allow_appending_values_to_same_key=True,
     )
 
     return sdk_no_wait(
@@ -3413,6 +3415,7 @@ def aks_agentpool_update(cmd, client, resource_group_name, cluster_name, nodepoo
         enable_strip=True,
         extract_kv=True,
         default_value={},
+        allow_appending_values_to_same_key=True,
     )
 
     return sdk_no_wait(
@@ -4161,6 +4164,7 @@ def aks_snapshot_create(cmd,    # pylint: disable=too-many-locals,too-many-state
         enable_strip=True,
         extract_kv=True,
         default_value={},
+        allow_appending_values_to_same_key=True,
     )
     return client.create_or_update(resource_group_name, name, snapshot, headers=aks_custom_headers)
 

src/azure-cli/azure/cli/command_modules/acs/decorator.py

@@ -4617,6 +4617,7 @@ def get_aks_custom_headers(self) -> Dict[str, str]:
             enable_strip=True,
             extract_kv=True,
             default_value={},
+            allow_appending_values_to_same_key=True,
         )
 
         # In create mode, add AAD session key to header.

src/azure-cli/azure/cli/command_modules/acs/tests/latest/test_validators.py

@@ -351,7 +351,7 @@ def test_extract_comma_separated_string(self):
             validators.extract_comma_separated_string(s12, extract_kv=True)
 
         s13 = "WindowsContainerRuntime=containerd,AKSHTTPCustomFeatures=Microsoft.ContainerService/CustomNodeConfigPreview"
-        t13 = validators.extract_comma_separated_string(s13, enable_strip=True, extract_kv=True, default_value={},)
+        t13 = validators.extract_comma_separated_string(s13, enable_strip=True, extract_kv=True, default_value={}, allow_appending_values_to_same_key=True)
         g13 = {"WindowsContainerRuntime": "containerd", "AKSHTTPCustomFeatures": "Microsoft.ContainerService/CustomNodeConfigPreview"}
         self.assertEqual(t13, g13)
 
@@ -360,6 +360,16 @@ def test_extract_comma_separated_string(self):
         g14 = {"": ""}
         self.assertEqual(t14, g14)
 
+        s15 = "WindowsContainerRuntime=containerd,AKSHTTPCustomFeatures=Microsoft.ContainerService/AKSTestFeaturePreview,AKSHTTPCustomFeatures=Microsoft.ContainerService/AKSExampleFeaturePreview"
+        t15 = validators.extract_comma_separated_string(s15, enable_strip=True, extract_kv=True, default_value={},)
+        g15 = {"WindowsContainerRuntime": "containerd", "AKSHTTPCustomFeatures": "Microsoft.ContainerService/AKSExampleFeaturePreview"}
+        self.assertEqual(t15, g15)
+
+        s16 = "WindowsContainerRuntime=containerd,AKSHTTPCustomFeatures=Microsoft.ContainerService/AKSTestFeaturePreview,AKSHTTPCustomFeatures=Microsoft.ContainerService/AKSExampleFeaturePreview"
+        t16 = validators.extract_comma_separated_string(s16, enable_strip=True, extract_kv=True, default_value={}, allow_appending_values_to_same_key=True)
+        g16 = {"WindowsContainerRuntime": "containerd", "AKSHTTPCustomFeatures": "Microsoft.ContainerService/AKSTestFeaturePreview,Microsoft.ContainerService/AKSExampleFeaturePreview"}
+        self.assertEqual(t16, g16)
+
 
 class CredentialFormatNamespace:
     def __init__(self, credential_format):
@@ -381,3 +391,7 @@ def test_valid_format(self):
         namespace = CredentialFormatNamespace(credential_format)
 
         validators.validate_credential_format(namespace)
+
+
+if __name__ == "__main__":
+    unittest.main()