Merge pull request #169 from Chainlit/willy/preprocess-steps

feat: add preprocessing functions for step ingestion

Author: willydouhard

literalai/client.py

@@ -2,7 +2,7 @@
 import json
 import os
 from contextlib import redirect_stdout
-from typing import Any, Dict, List, Optional, Union
+from typing import Any, Callable, Dict, List, Optional, Union
 
 from traceloop.sdk import Traceloop
 from typing_extensions import deprecated
@@ -29,6 +29,7 @@
     MessageStepType,
     Step,
     StepContextManager,
+    StepDict,
     TrueStepType,
     step_decorator,
 )
@@ -94,15 +95,55 @@ def __init__(
 
     def to_sync(self) -> "LiteralClient":
         if isinstance(self.api, AsyncLiteralAPI):
-            return LiteralClient(
+            sync_client = LiteralClient(
                 batch_size=self.event_processor.batch_size,
                 api_key=self.api.api_key,
                 url=self.api.url,
                 disabled=self.disabled,
             )
+            if self.event_processor.preprocess_steps_function:
+                sync_client.event_processor.set_preprocess_steps_function(
+                    self.event_processor.preprocess_steps_function
+                )
+
+            return sync_client
         else:
             return self  # type: ignore
 
+    def set_preprocess_steps_function(
+        self,
+        preprocess_steps_function: Optional[
+            Callable[[List["StepDict"]], List["StepDict"]]
+        ],
+    ) -> None:
+        """
+        Set a function that will preprocess steps before sending them to the API.
+        This can be used for tasks like PII removal or other data transformations.
+
+        The preprocess function should:
+        - Accept a list of StepDict objects as input
+        - Return a list of modified StepDict objects
+        - Be thread-safe as it will be called from a background thread
+        - Handle exceptions internally to avoid disrupting the event processing
+
+        Example:
+        ```python
+        def remove_pii(steps):
+            # Process steps to remove PII data
+            for step in steps:
+                if step.get("content"):
+                    step["content"] = my_pii_removal_function(step["content"])
+            return steps
+
+        client.set_preprocess_steps_function(remove_pii)
+        ```
+
+        Args:
+            preprocess_steps_function (Callable[[List["StepDict"]], List["StepDict"]]):
+                Function that takes a list of steps and returns a processed list
+        """
+        self.event_processor.set_preprocess_steps_function(preprocess_steps_function)
+
     @deprecated("Use Literal.initialize instead")
     def instrument_openai(self):
         """

literalai/event_processor.py

@@ -4,7 +4,7 @@
 import threading
 import time
 import traceback
-from typing import TYPE_CHECKING, List
+from typing import TYPE_CHECKING, Callable, List, Optional
 
 logger = logging.getLogger(__name__)
 
@@ -31,7 +31,15 @@ class EventProcessor:
     batch: List["StepDict"]
     batch_timeout: float = 5.0
 
-    def __init__(self, api: "LiteralAPI", batch_size: int = 1, disabled: bool = False):
+    def __init__(
+        self,
+        api: "LiteralAPI",
+        batch_size: int = 1,
+        disabled: bool = False,
+        preprocess_steps_function: Optional[
+            Callable[[List["StepDict"]], List["StepDict"]]
+        ] = None,
+    ):
         self.stop_event = threading.Event()
         self.batch_size = batch_size
         self.api = api
@@ -40,6 +48,7 @@ def __init__(self, api: "LiteralAPI", batch_size: int = 1, disabled: bool = Fals
         self.processing_counter = 0
         self.counter_lock = threading.Lock()
         self.last_batch_time = time.time()
+        self.preprocess_steps_function = preprocess_steps_function
         self.processing_thread = threading.Thread(
             target=self._process_events, daemon=True
         )
@@ -56,6 +65,22 @@ async def a_add_events(self, event: "StepDict"):
             self.processing_counter += 1
         await to_thread(self.event_queue.put, event)
 
+    def set_preprocess_steps_function(
+        self,
+        preprocess_steps_function: Optional[
+            Callable[[List["StepDict"]], List["StepDict"]]
+        ],
+    ):
+        """
+        Set a function that will preprocess steps before sending them to the API.
+        The function should take a list of StepDict objects and return a list of processed StepDict objects.
+        This can be used for tasks like PII removal.
+
+        Args:
+            preprocess_steps_function (Callable[[List["StepDict"]], List["StepDict"]]): The preprocessing function
+        """
+        self.preprocess_steps_function = preprocess_steps_function
+
     def _process_events(self):
         while True:
             batch = []
@@ -83,6 +108,24 @@ def _process_events(self):
 
     def _try_process_batch(self, batch: List):
         try:
+            # Apply preprocessing function if it exists
+            if self.preprocess_steps_function is not None:
+                try:
+                    processed_batch = self.preprocess_steps_function(batch)
+                    # Only use the processed batch if it's valid
+                    if processed_batch is not None and isinstance(
+                        processed_batch, list
+                    ):
+                        batch = processed_batch
+                    else:
+                        logger.warning(
+                            "Preprocess function returned invalid result, using original batch"
+                        )
+                except Exception as e:
+                    logger.error(f"Error in preprocess function: {str(e)}")
+                    logger.error(traceback.format_exc())
+                    # Continue with the original batch
+
             return self.api.send_steps(batch)
         except Exception:
             logger.error(f"Failed to send steps: {traceback.format_exc()}")

literalai/version.py

@@ -1 +1 @@
-__version__ = "0.1.202"
+__version__ = "0.1.3"

setup.py

@@ -2,7 +2,7 @@
 
 setup(
     name="literalai",
-    version="0.1.202",  # update version in literalai/version.py
+    version="0.1.3",  # update version in literalai/version.py
     description="An SDK for observability in Python applications",
     long_description=open("README.md").read(),
     long_description_content_type="text/markdown",

tests/e2e/test_e2e.py

@@ -801,3 +801,97 @@ async def test_environment(self, staging_client: LiteralClient):
         persisted_run = staging_client.api.get_step(run_id)
         assert persisted_run is not None
         assert persisted_run.environment == "staging"
+
+    @pytest.mark.timeout(5)
+    async def test_pii_removal(
+        self, client: LiteralClient, async_client: AsyncLiteralClient
+    ):
+        """Test that PII is properly removed by the preprocess function."""
+        import re
+
+        # Define a PII removal function
+        def remove_pii(steps):
+            # Patterns for common PII
+            email_pattern = r"\b[A-Za-z0-9._%+-]+@[A-Za-z0-9.-]+\.[A-Z|a-z]{2,}\b"
+            phone_pattern = r"\b(\+\d{1,2}\s?)?\(?\d{3}\)?[\s.-]?\d{3}[\s.-]?\d{4}\b"
+            ssn_pattern = r"\b\d{3}[-\s]?\d{2}[-\s]?\d{4}\b"
+
+            for step in steps:
+                # Process content field if it exists
+                if "output" in step and step["output"]["content"]:
+                    # Replace emails with [EMAIL REDACTED]
+                    step["output"]["content"] = re.sub(
+                        email_pattern, "[EMAIL REDACTED]", step["output"]["content"]
+                    )
+
+                    # Replace phone numbers with [PHONE REDACTED]
+                    step["output"]["content"] = re.sub(
+                        phone_pattern, "[PHONE REDACTED]", step["output"]["content"]
+                    )
+
+                    # Replace SSNs with [SSN REDACTED]
+                    step["output"]["content"] = re.sub(
+                        ssn_pattern, "[SSN REDACTED]", step["output"]["content"]
+                    )
+
+            return steps
+
+        # Set the PII removal function on the client
+        client.set_preprocess_steps_function(remove_pii)
+
+        @client.thread
+        def thread_with_pii():
+            thread = client.get_current_thread()
+
+            # User message with PII
+            user_step = client.message(
+                content="My email is test@example.com and my phone is (123) 456-7890. My SSN is 123-45-6789.",
+                type="user_message",
+                metadata={"contact_info": "Call me at 987-654-3210"},
+            )
+            user_step_id = user_step.id
+
+            # Assistant message with PII reference
+            assistant_step = client.message(
+                content="I'll contact you at test@example.com", type="assistant_message"
+            )
+            assistant_step_id = assistant_step.id
+
+            return thread.id, user_step_id, assistant_step_id
+
+        # Run the thread
+        thread_id, user_step_id, assistant_step_id = thread_with_pii()
+
+        # Wait for processing to occur
+        client.flush()
+
+        # Fetch the steps and verify PII was removed
+        user_step = client.api.get_step(id=user_step_id)
+        assistant_step = client.api.get_step(id=assistant_step_id)
+
+        assert user_step
+        assert assistant_step
+
+        user_step_output = user_step.output["content"]  # type: ignore
+
+        # Check user message
+        assert "test@example.com" not in user_step_output
+        assert "(123) 456-7890" not in user_step_output
+        assert "123-45-6789" not in user_step_output
+        assert "[EMAIL REDACTED]" in user_step_output
+        assert "[PHONE REDACTED]" in user_step_output
+        assert "[SSN REDACTED]" in user_step_output
+
+        assistant_step_output = assistant_step.output["content"]  # type: ignore
+
+        # Check assistant message
+        assert "test@example.com" not in assistant_step_output
+        assert "[EMAIL REDACTED]" in assistant_step_output
+
+        # Clean up
+        client.api.delete_step(id=user_step_id)
+        client.api.delete_step(id=assistant_step_id)
+        client.api.delete_thread(id=thread_id)
+
+        # Reset the preprocess function to avoid affecting other tests
+        client.set_preprocess_steps_function(None)