fix(llmobs): fix parsing nontype chunk.delta in openai streamed responses (#14046)

In openai streamed responses chunk.delta can be set to `None`, so if not
hasattr(chunk, "delta") evaluates to true but then this line throws
since delta is None:
if getattr(chunk.delta, "role") and not message.get("role"):

This PR changes the logic to use uniformly use our `_get_attr` util
function while parsing streamed chunks

## Checklist
- [x] PR author has checked that all the criteria below are met
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- The PR description articulates the motivation for the change
- The change includes tests OR the PR description describes a testing
strategy
- The PR description notes risks associated with the change, if any
- Newly-added code is easy to change
- The change follows the [library release note
guidelines](https://ddtrace.readthedocs.io/en/stable/releasenotes.html)
- The change includes or references documentation updates if necessary
- Backport labels are set (if
[applicable](https://ddtrace.readthedocs.io/en/latest/contributing.html#backporting))

## Reviewer Checklist
- [x] Reviewer has checked that all the criteria below are met 
- Title is accurate
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[API](https://ddtrace.readthedocs.io/en/stable/versioning.html#interfaces)
changes
- Testing strategy adequately addresses listed risks
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---------

Co-authored-by: Sam Brenner <[email protected]>

Author: lievan

ddtrace/llmobs/_integrations/utils.py

@@ -645,24 +645,24 @@ def openai_construct_message_from_streamed_chunks(streamed_chunks: List[Any]) ->
     """
     message: Dict[str, Any] = {"content": "", "tool_calls": []}
     for chunk in streamed_chunks:
-        if getattr(chunk, "usage", None):
+        if _get_attr(chunk, "usage", None):
             message["usage"] = chunk.usage
-        if not hasattr(chunk, "delta"):
+        if not _get_attr(chunk, "delta", None):
             continue
-        if getattr(chunk, "index", None) and not message.get("index"):
+        if _get_attr(chunk, "index", None) and not message.get("index"):
             message["index"] = chunk.index
-        if getattr(chunk.delta, "role") and not message.get("role"):
+        if _get_attr(chunk.delta, "role", None) and not message.get("role"):
             message["role"] = chunk.delta.role
-        if getattr(chunk, "finish_reason", None) and not message.get("finish_reason"):
+        if _get_attr(chunk, "finish_reason", None) and not message.get("finish_reason"):
             message["finish_reason"] = chunk.finish_reason
-        chunk_content = getattr(chunk.delta, "content", "")
+        chunk_content = _get_attr(chunk.delta, "content", "")
         if chunk_content:
             message["content"] += chunk_content
             continue
-        function_call = getattr(chunk.delta, "function_call", None)
+        function_call = _get_attr(chunk.delta, "function_call", None)
         if function_call:
             openai_construct_tool_call_from_streamed_chunk(message["tool_calls"], function_call_chunk=function_call)
-        tool_calls = getattr(chunk.delta, "tool_calls", None)
+        tool_calls = _get_attr(chunk.delta, "tool_calls", None)
         if not tool_calls:
             continue
         for tool_call in tool_calls:

releasenotes/notes/fix-oai-resp-bug-75e91a1061a66449.yaml

@@ -0,0 +1,4 @@
+---
+fixes:
+  - |
+    LLM Observability, openai: This fix resolves an issue where openai tracing caused an ``AttributeError`` while parsing ``NoneType`` streamed chunk deltas.