fix(tracing): prevent mutation of user options when tracing is enabled

When tracing is enabled, the system was directly modifying the user's
original GenerationOptions object, causing instability when the same
options were reused across multiple calls.

This fix creates a copy of the options before modification, ensuring
the original user options remain unchanged while maintaining full
tracing functionality

Author: Pouyanpi

nemoguardrails/rails/llm/llmrails.py

@@ -839,6 +839,12 @@ async def generate_async(
         if self.config.tracing.enabled:
             if options is None:
                 options = GenerationOptions()
+            else:
+                # create a copy of the options to avoid modifying the original
+                options = GenerationOptions(**options.model_dump())
+
+            # enable log options
+            # it is aggressive, but these are required for tracing
             if (
                 not options.log.activated_rails
                 or not options.log.llm_calls

tests/test_tracing.py

@@ -14,23 +14,25 @@
 # limitations under the License.
 
 import asyncio
-import os
 import unittest
 from unittest.mock import AsyncMock, MagicMock, patch
 
 import pytest
 
-from nemoguardrails import LLMRails
+from nemoguardrails import LLMRails, RailsConfig
 from nemoguardrails.logging.explain import LLMCallInfo
-from nemoguardrails.rails.llm.config import RailsConfig, TracingConfig
 from nemoguardrails.rails.llm.options import (
     ActivatedRail,
     ExecutedAction,
     GenerationLog,
+    GenerationLogOptions,
+    GenerationOptions,
+    GenerationRailsOptions,
     GenerationResponse,
 )
 from nemoguardrails.tracing.adapters.base import InteractionLogAdapter
 from nemoguardrails.tracing.tracer import Tracer, new_uuid
+from tests.utils import TestChat
 
 
 class TestTracer(unittest.TestCase):
@@ -239,5 +241,197 @@ async def test_tracing_enable_no_crash_issue_1093(mockTracer):
     assert res.response != None
 
 
+@pytest.mark.asyncio
+async def test_tracing_does_not_mutate_user_options():
+    """Test that tracing doesn't modify the user's original GenerationOptions object.
+
+    This test verifies the core fix: when tracing is enabled, the user's options
+    should not be modified. Before the fix, this test would have failed
+    because the original options object was being mutated.
+    """
+
+    config = RailsConfig.from_content(
+        colang_content="""
+        define user express greeting
+            "hello"
+
+        define flow
+            user express greeting
+            bot express greeting
+
+        define bot express greeting
+            "Hello! How can I assist you today?"
+        """,
+        config={
+            "models": [],
+            "tracing": {"enabled": True, "adapters": [{"name": "FileSystem"}]},
+        },
+    )
+
+    chat = TestChat(
+        config,
+        llm_completions=[
+            "user express greeting",
+            "bot express greeting",
+            "Hello! How can I assist you today?",
+        ],
+    )
+
+    user_options = GenerationOptions(
+        log=GenerationLogOptions(
+            activated_rails=False,
+            llm_calls=False,
+            internal_events=False,
+            colang_history=False,
+        )
+    )
+
+    original_activated_rails = user_options.log.activated_rails
+    original_llm_calls = user_options.log.llm_calls
+    original_internal_events = user_options.log.internal_events
+    original_colang_history = user_options.log.colang_history
+
+    # mock file operations to focus on the mutation issue
+    with patch.object(Tracer, "export_async", return_value=None):
+        response = await chat.app.generate_async(
+            messages=[{"role": "user", "content": "hello"}], options=user_options
+        )
+
+        # main fix: no mutation
+        assert (
+            user_options.log.activated_rails == original_activated_rails
+        ), "User's original options were modified! This causes instability."
+        assert (
+            user_options.log.llm_calls == original_llm_calls
+        ), "User's original options were modified! This causes instability."
+        assert (
+            user_options.log.internal_events == original_internal_events
+        ), "User's original options were modified! This causes instability."
+        assert (
+            user_options.log.colang_history == original_colang_history
+        ), "User's original options were modified! This causes instability."
+
+        # verify that tracing still works
+        assert response.log is not None, "Tracing should still work correctly"
+        assert (
+            response.log.activated_rails is not None
+        ), "Should have activated rails data"
+
+
+@pytest.mark.asyncio
+async def test_tracing_with_none_options():
+    """Test that tracing works correctly when no options are provided.
+
+    This verifies that the fix doesn't break the case where users don't
+    provide any options at all.
+    """
+
+    config = RailsConfig.from_content(
+        colang_content="""
+        define user express greeting
+            "hello"
+
+        define flow
+            user express greeting
+            bot express greeting
+
+        define bot express greeting
+            "Hello! How can I assist you today?"
+        """,
+        config={
+            "models": [],
+            "tracing": {"enabled": True, "adapters": [{"name": "FileSystem"}]},
+        },
+    )
+
+    chat = TestChat(
+        config,
+        llm_completions=[
+            "user express greeting",
+            "bot express greeting",
+            "Hello! How can I assist you today?",
+        ],
+    )
+
+    with patch.object(Tracer, "export_async", return_value=None):
+        response = await chat.app.generate_async(
+            messages=[{"role": "user", "content": "hello"}], options=None
+        )
+
+        assert response.log is not None
+        assert response.log.activated_rails is not None
+        assert response.log.stats is not None
+
+
+@pytest.mark.asyncio
+async def test_tracing_aggressive_override_when_all_disabled():
+    """Test that tracing aggressively enables all logging when user disables all options.
+
+    When user disables all three tracing related options, tracing still enables
+    ALL of them to ensure comprehensive logging data.
+    """
+
+    config = RailsConfig.from_content(
+        colang_content="""
+        define user express greeting
+            "hello"
+
+        define flow
+            user express greeting
+            bot express greeting
+
+        define bot express greeting
+            "Hello! How can I assist you today?"
+        """,
+        config={
+            "models": [],
+            "tracing": {"enabled": True, "adapters": [{"name": "FileSystem"}]},
+        },
+    )
+
+    chat = TestChat(
+        config,
+        llm_completions=[
+            "user express greeting",
+            "bot express greeting",
+            "Hello! How can I assist you today?",
+        ],
+    )
+
+    # user explicitly disables ALL tracing related options
+    user_options = GenerationOptions(
+        log=GenerationLogOptions(
+            activated_rails=False,
+            llm_calls=False,
+            internal_events=False,
+            colang_history=True,
+        )
+    )
+
+    original_activated_rails = user_options.log.activated_rails
+    original_llm_calls = user_options.log.llm_calls
+    original_internal_events = user_options.log.internal_events
+    original_colang_history = user_options.log.colang_history
+
+    with patch.object(Tracer, "export_async", return_value=None):
+        response = await chat.app.generate_async(
+            messages=[{"role": "user", "content": "hello"}], options=user_options
+        )
+
+        assert user_options.log.activated_rails == original_activated_rails
+        assert user_options.log.llm_calls == original_llm_calls
+        assert user_options.log.internal_events == original_internal_events
+        assert user_options.log.colang_history == original_colang_history
+
+        assert response.log is not None
+        assert response.log.activated_rails is not None
+        assert response.log.llm_calls is not None
+        assert response.log.internal_events is not None
+
+        assert user_options.log.activated_rails == original_activated_rails
+        assert user_options.log.llm_calls == original_llm_calls
+        assert user_options.log.internal_events == original_internal_events
+
+
 if __name__ == "__main__":
     unittest.main()