feat(llm-observability): add langchain integration (#159)

* feat(ai): LangChain integration v0.1

* test: langchain integration tests

* test: langchain-openai for v2 and v3

* chore: reorganize imports

* fix: ci

* fix: set python on ci to 3.9

* fix: upgrade ci for python 3.9

* fix: fallback for distinct_id

* fix: personless events for omitted distinct_ids

* fix: review comments

* feat: base url retrieval

Author: skoob13

.github/workflows/ci.yml

@@ -33,7 +33,7 @@ jobs:
             - name: Check formatting with black
               run: |
                   black --check .
-            
+
             - name: Lint with flake8
               run: |
                   flake8 posthog --ignore E501
@@ -51,10 +51,10 @@ jobs:
               with:
                   fetch-depth: 1
 
-            - name: Set up Python 3.8
+            - name: Set up Python 3.9
               uses: actions/setup-python@v2
               with:
-                  python-version: 3.8
+                  python-version: 3.9
 
             - name: Install requirements.txt dependencies with pip
               run: |

.gitignore

@@ -15,4 +15,5 @@ posthog-analytics
 .idea
 .python-version
 .coverage
-pyrightconfig.json
+pyrightconfig.json
+.env

llm_observability_examples.py

@@ -2,7 +2,7 @@
 import uuid
 
 import posthog
-from posthog.ai import AsyncOpenAI, OpenAI
+from posthog.ai.openai import AsyncOpenAI, OpenAI
 
 # Example credentials - replace these with your own or use environment variables
 posthog.project_api_key = os.getenv("POSTHOG_PROJECT_API_KEY", "your-project-api-key")

posthog/ai/__init__.py

@@ -1,4 +0,0 @@
-from .providers.openai.openai import OpenAI
-from .providers.openai.openai_async import AsyncOpenAI
-
-__all__ = ["OpenAI", "AsyncOpenAI"]

posthog/ai/langchain/__init__.py

@@ -0,0 +1,3 @@
+from .callbacks import CallbackHandler
+
+__all__ = ["CallbackHandler"]