chore: update the groq inference impl to use openai-python for openai-compat functions (#3348)

# What does this PR do?

update Groq inference provider to use OpenAIMixin for openai-compat
endpoints

changes on api.groq.com -
- json_schema is now supported for specific models, see
https://console.groq.com/docs/structured-outputs#supported-models
- response_format with streaming is now supported for models that
support response_format
- groq no longer returns a 400 error if tools are provided and
tool_choice is not "required"


## Test Plan

```
$ GROQ_API_KEY=... uv run llama stack build --image-type venv --providers inference=remote::groq --run
...
$ LLAMA_STACK_CONFIG=http://localhost:8321 uv run --group test pytest -v -ra --text-model groq/llama-3.3-70b-versatile tests/integration/inference/test_openai_completion.py -k 'not store'
...
SKIPPED [3] tests/integration/inference/test_openai_completion.py:44: Model groq/llama-3.3-70b-versatile hosted by remote::groq doesn't support OpenAI completions.
SKIPPED [3] tests/integration/inference/test_openai_completion.py:94: Model groq/llama-3.3-70b-versatile hosted by remote::groq doesn't support vllm extra_body parameters.
SKIPPED [4] tests/integration/inference/test_openai_completion.py:73: Model groq/llama-3.3-70b-versatile hosted by remote::groq doesn't support n param.
SKIPPED [1] tests/integration/inference/test_openai_completion.py💯 Model groq/llama-3.3-70b-versatile hosted by remote::groq doesn't support chat completion calls with base64 encoded files.
======================= 8 passed, 11 skipped, 8 deselected, 2 warnings in 5.13s ========================
```

---------

Co-authored-by: raghotham <rsm@meta.com>

llama_stack/providers/registry/inference.py

@@ -248,7 +248,7 @@ Available Models:
             api=Api.inference,
             adapter=AdapterSpec(
                 adapter_type="groq",
-                pip_packages=["litellm"],
+                pip_packages=["litellm", "openai"],
                 module="llama_stack.providers.remote.inference.groq",
                 config_class="llama_stack.providers.remote.inference.groq.GroqConfig",
                 provider_data_validator="llama_stack.providers.remote.inference.groq.config.GroqProviderDataValidator",

llama_stack/providers/remote/inference/groq/groq.py

@@ -4,30 +4,15 @@
 # This source code is licensed under the terms described in the LICENSE file in
 # the root directory of this source tree.
 
-from collections.abc import AsyncIterator
-from typing import Any
 
-from openai import AsyncOpenAI
-
-from llama_stack.apis.inference import (
-    OpenAIChatCompletion,
-    OpenAIChatCompletionChunk,
-    OpenAIChoiceDelta,
-    OpenAIChunkChoice,
-    OpenAIMessageParam,
-    OpenAIResponseFormatParam,
-    OpenAISystemMessageParam,
-)
 from llama_stack.providers.remote.inference.groq.config import GroqConfig
 from llama_stack.providers.utils.inference.litellm_openai_mixin import LiteLLMOpenAIMixin
-from llama_stack.providers.utils.inference.openai_compat import (
+from llama_stack.providers.utils.inference.openai_mixin import OpenAIMixin
-    prepare_openai_completion_params,
-)
 
 from .models import MODEL_ENTRIES
 
 
-class GroqInferenceAdapter(LiteLLMOpenAIMixin):
+class GroqInferenceAdapter(OpenAIMixin, LiteLLMOpenAIMixin):
     _config: GroqConfig
 
     def __init__(self, config: GroqConfig):
@@ -40,122 +25,14 @@ class GroqInferenceAdapter(LiteLLMOpenAIMixin):
         )
         self.config = config
 
+    # Delegate the client data handling get_api_key method to LiteLLMOpenAIMixin
+    get_api_key = LiteLLMOpenAIMixin.get_api_key
+
+    def get_base_url(self) -> str:
+        return f"{self.config.url}/openai/v1"
+
     async def initialize(self):
         await super().initialize()
 
     async def shutdown(self):
         await super().shutdown()
-
-    def _get_openai_client(self) -> AsyncOpenAI:
-        return AsyncOpenAI(
-            base_url=f"{self.config.url}/openai/v1",
-            api_key=self.get_api_key(),
-        )
-
-    async def openai_chat_completion(
-        self,
-        model: str,
-        messages: list[OpenAIMessageParam],
-        frequency_penalty: float | None = None,
-        function_call: str | dict[str, Any] | None = None,
-        functions: list[dict[str, Any]] | None = None,
-        logit_bias: dict[str, float] | None = None,
-        logprobs: bool | None = None,
-        max_completion_tokens: int | None = None,
-        max_tokens: int | None = None,
-        n: int | None = None,
-        parallel_tool_calls: bool | None = None,
-        presence_penalty: float | None = None,
-        response_format: OpenAIResponseFormatParam | None = None,
-        seed: int | None = None,
-        stop: str | list[str] | None = None,
-        stream: bool | None = None,
-        stream_options: dict[str, Any] | None = None,
-        temperature: float | None = None,
-        tool_choice: str | dict[str, Any] | None = None,
-        tools: list[dict[str, Any]] | None = None,
-        top_logprobs: int | None = None,
-        top_p: float | None = None,
-        user: str | None = None,
-    ) -> OpenAIChatCompletion | AsyncIterator[OpenAIChatCompletionChunk]:
-        model_obj = await self.model_store.get_model(model)
-
-        # Groq does not support json_schema response format, so we need to convert it to json_object
-        if response_format and response_format.type == "json_schema":
-            response_format.type = "json_object"
-            schema = response_format.json_schema.get("schema", {})
-            response_format.json_schema = None
-            json_instructions = f"\nYour response should be a JSON object that matches the following schema: {schema}"
-            if messages and messages[0].role == "system":
-                messages[0].content = messages[0].content + json_instructions
-            else:
-                messages.insert(0, OpenAISystemMessageParam(content=json_instructions))
-
-        # Groq returns a 400 error if tools are provided but none are called
-        # So, set tool_choice to "required" to attempt to force a call
-        if tools and (not tool_choice or tool_choice == "auto"):
-            tool_choice = "required"
-
-        params = await prepare_openai_completion_params(
-            model=model_obj.provider_resource_id,
-            messages=messages,
-            frequency_penalty=frequency_penalty,
-            function_call=function_call,
-            functions=functions,
-            logit_bias=logit_bias,
-            logprobs=logprobs,
-            max_completion_tokens=max_completion_tokens,
-            max_tokens=max_tokens,
-            n=n,
-            parallel_tool_calls=parallel_tool_calls,
-            presence_penalty=presence_penalty,
-            response_format=response_format,
-            seed=seed,
-            stop=stop,
-            stream=stream,
-            stream_options=stream_options,
-            temperature=temperature,
-            tool_choice=tool_choice,
-            tools=tools,
-            top_logprobs=top_logprobs,
-            top_p=top_p,
-            user=user,
-        )
-
-        # Groq does not support streaming requests that set response_format
-        fake_stream = False
-        if stream and response_format:
-            params["stream"] = False
-            fake_stream = True
-
-        response = await self._get_openai_client().chat.completions.create(**params)
-
-        if fake_stream:
-            chunk_choices = []
-            for choice in response.choices:
-                delta = OpenAIChoiceDelta(
-                    content=choice.message.content,
-                    role=choice.message.role,
-                    tool_calls=choice.message.tool_calls,
-                )
-                chunk_choice = OpenAIChunkChoice(
-                    delta=delta,
-                    finish_reason=choice.finish_reason,
-                    index=choice.index,
-                    logprobs=None,
-                )
-                chunk_choices.append(chunk_choice)
-            chunk = OpenAIChatCompletionChunk(
-                id=response.id,
-                choices=chunk_choices,
-                object="chat.completion.chunk",
-                created=response.created,
-                model=response.model,
-            )
-
-            async def _fake_stream_generator():
-                yield chunk
-
-            return _fake_stream_generator()
-        else:
-            return response

tests/unit/providers/inference/test_inference_client_caching.py

@@ -33,8 +33,7 @@ def test_groq_provider_openai_client_caching():
         with request_provider_data_context(
             {"x-llamastack-provider-data": json.dumps({inference_adapter.provider_data_api_key_field: api_key})}
         ):
-            openai_client = inference_adapter._get_openai_client()
+            assert inference_adapter.client.api_key == api_key
-            assert openai_client.api_key == api_key
 
 
 def test_openai_provider_openai_client_caching():