Python: Support DefaultAzureCredential for AzureAI Inference (#8862)

### Motivation and Context

In recent work, the DefaultAzureCredential path was added for
AzureOpenAI, but was missed for AzureAI inference.

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### Description

Adding support for default azure credential for AzureAI inference and
its tests.

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These notes will help understanding how your code works. Thanks! -->

### Contribution Checklist

<!-- Before submitting this PR, please make sure: -->

- [X] The code builds clean without any errors or warnings
- [X] The PR follows the [SK Contribution
Guidelines](https://github.com/microsoft/semantic-kernel/blob/main/CONTRIBUTING.md)
and the [pre-submission formatting
script](https://github.com/microsoft/semantic-kernel/blob/main/CONTRIBUTING.md#development-scripts)
raises no violations
- [X] All unit tests pass, and I have added new tests where possible
- [X] I didn't break anyone 😄

.github/workflows/python-integration-tests.yml

@@ -241,7 +241,7 @@ jobs:
         if: matrix.os == 'ubuntu-latest'
         run: docker run -d --name redis-stack-server -p 6379:6379 redis/redis-stack-server:latest
       - name: Azure CLI Login
-        if: github.event_name != 'pull_request' && matrix.integration-tests
+        if: github.event_name != 'pull_request'
         uses: azure/login@v2
         with:
           client-id: ${{ secrets.AZURE_CLIENT_ID }}

python/semantic_kernel/connectors/ai/azure_ai_inference/services/azure_ai_inference_chat_completion.py

@@ -21,6 +21,7 @@
     StreamingChatCompletionsUpdate,
 )
 from azure.core.credentials import AzureKeyCredential
+from azure.identity import DefaultAzureCredential
 from pydantic import ValidationError
 
 from semantic_kernel.connectors.ai.azure_ai_inference import (
@@ -34,6 +35,7 @@
 from semantic_kernel.connectors.ai.function_call_choice_configuration import FunctionCallChoiceConfiguration
 from semantic_kernel.connectors.ai.function_calling_utils import update_settings_from_function_call_configuration
 from semantic_kernel.connectors.ai.function_choice_behavior import FunctionChoiceType
+from semantic_kernel.connectors.ai.open_ai.const import DEFAULT_AZURE_API_VERSION
 from semantic_kernel.contents.chat_history import ChatHistory
 from semantic_kernel.contents.chat_message_content import ITEM_TYPES, ChatMessageContent
 from semantic_kernel.contents.function_call_content import FunctionCallContent
@@ -106,11 +108,24 @@ def __init__(
             except ValidationError as e:
                 raise ServiceInitializationError(f"Failed to validate Azure AI Inference settings: {e}") from e
 
-            client = ChatCompletionsClient(
-                endpoint=str(azure_ai_inference_settings.endpoint),
-                credential=AzureKeyCredential(azure_ai_inference_settings.api_key.get_secret_value()),
-                user_agent=SEMANTIC_KERNEL_USER_AGENT,
-            )
+            endpoint_to_use: str = str(azure_ai_inference_settings.endpoint)
+            if azure_ai_inference_settings.api_key is not None:
+                client = ChatCompletionsClient(
+                    endpoint=endpoint_to_use,
+                    credential=AzureKeyCredential(azure_ai_inference_settings.api_key.get_secret_value()),
+                    user_agent=SEMANTIC_KERNEL_USER_AGENT,
+                )
+            else:
+                # Try to create the client with a DefaultAzureCredential
+                client = (
+                    ChatCompletionsClient(
+                        endpoint=endpoint_to_use,
+                        credential=DefaultAzureCredential(),
+                        credential_scopes=["https://cognitiveservices.azure.com/.default"],
+                        api_version=DEFAULT_AZURE_API_VERSION,
+                        user_agent=SEMANTIC_KERNEL_USER_AGENT,
+                    ),
+                )
 
         super().__init__(
             ai_model_id=ai_model_id,

python/semantic_kernel/connectors/ai/azure_ai_inference/services/azure_ai_inference_text_embedding.py

@@ -14,12 +14,15 @@
 else:
     from typing_extensions import override  # pragma: no cover
 
+from azure.identity import DefaultAzureCredential
+
 from semantic_kernel.connectors.ai.azure_ai_inference.azure_ai_inference_prompt_execution_settings import (
     AzureAIInferenceEmbeddingPromptExecutionSettings,
 )
 from semantic_kernel.connectors.ai.azure_ai_inference.azure_ai_inference_settings import AzureAIInferenceSettings
 from semantic_kernel.connectors.ai.azure_ai_inference.services.azure_ai_inference_base import AzureAIInferenceBase
 from semantic_kernel.connectors.ai.embeddings.embedding_generator_base import EmbeddingGeneratorBase
+from semantic_kernel.connectors.ai.open_ai.const import DEFAULT_AZURE_API_VERSION
 from semantic_kernel.exceptions.service_exceptions import ServiceInitializationError
 from semantic_kernel.utils.experimental_decorator import experimental_class
 from semantic_kernel.utils.telemetry.user_agent import SEMANTIC_KERNEL_USER_AGENT
@@ -72,11 +75,22 @@ def __init__(
             except ValidationError as e:
                 raise ServiceInitializationError(f"Failed to validate Azure AI Inference settings: {e}") from e
 
-            client = EmbeddingsClient(
-                endpoint=str(azure_ai_inference_settings.endpoint),
-                credential=AzureKeyCredential(azure_ai_inference_settings.api_key.get_secret_value()),
-                user_agent=SEMANTIC_KERNEL_USER_AGENT,
-            )
+            endpoint = str(azure_ai_inference_settings.endpoint)
+            if azure_ai_inference_settings.api_key is not None:
+                client = EmbeddingsClient(
+                    endpoint=endpoint,
+                    credential=AzureKeyCredential(azure_ai_inference_settings.api_key.get_secret_value()),
+                    user_agent=SEMANTIC_KERNEL_USER_AGENT,
+                )
+            else:
+                # Try to create the client with a DefaultAzureCredential
+                client = EmbeddingsClient(
+                    endpoint=endpoint,
+                    credential=DefaultAzureCredential(),
+                    credential_scopes=["https://cognitiveservices.azure.com/.default"],
+                    api_version=DEFAULT_AZURE_API_VERSION,
+                    user_agent=SEMANTIC_KERNEL_USER_AGENT,
+                )
 
         super().__init__(
             ai_model_id=ai_model_id,

python/tests/integration/embeddings/test_azure_ai_inference_embedding_service.py

@@ -3,11 +3,12 @@
 
 import pytest
 from azure.ai.inference.aio import EmbeddingsClient
-from azure.core.credentials import AzureKeyCredential
+from azure.identity import DefaultAzureCredential
 
 from semantic_kernel.connectors.ai.azure_ai_inference.services.azure_ai_inference_text_embedding import (
     AzureAIInferenceTextEmbedding,
 )
+from semantic_kernel.connectors.ai.open_ai.const import DEFAULT_AZURE_API_VERSION
 from semantic_kernel.connectors.ai.open_ai.settings.azure_open_ai_settings import AzureOpenAISettings
 from semantic_kernel.core_plugins.text_memory_plugin import TextMemoryPlugin
 from semantic_kernel.kernel import Kernel
@@ -21,14 +22,14 @@ async def test_azure_ai_inference_embedding_service(kernel: Kernel):
     azure_openai_settings = AzureOpenAISettings.create()
     endpoint = azure_openai_settings.endpoint
     deployment_name = azure_openai_settings.embedding_deployment_name
-    api_key = azure_openai_settings.api_key.get_secret_value()
 
     embeddings_gen = AzureAIInferenceTextEmbedding(
         ai_model_id=deployment_name,
         client=EmbeddingsClient(
             endpoint=f'{str(endpoint).strip("/")}/openai/deployments/{deployment_name}',
-            credential=AzureKeyCredential(""),
-            headers={"api-key": api_key},
+            credential=DefaultAzureCredential(),
+            credential_scopes=["https://cognitiveservices.azure.com/.default"],
+            api_version=DEFAULT_AZURE_API_VERSION,
         ),
     )