feat: Migrate langchain functionality into braintrust package

.github/workflows/checks.yaml

@@ -73,14 +73,6 @@ jobs:
 
   langchain-py:
     uses: ./.github/workflows/langchain-py-test.yaml
-    strategy:
-      fail-fast: false
-      matrix:
-        python-version: ["3.10", "3.11", "3.12", "3.13"]
-        os: [ubuntu-latest, windows-latest]
-    with:
-      python-version: ${{ matrix.python-version }}
-      os: ${{ matrix.os }}
 
   upload-wheel:
     needs: build

.github/workflows/langchain-py-test.yaml

@@ -2,23 +2,12 @@ name: langchain-py
 
 on:
   workflow_call:
-    inputs:
-      python-version:
-        required: true
-        type: string
-      os:
-        required: true
-        type: string
 
 jobs:
   test:
-    runs-on: ${{ inputs.os }}
+    runs-on: ubuntu-latest
     timeout-minutes: 15
 
-    defaults:
-      run:
-        working-directory: integrations/langchain-py
-
     steps:
       - uses: actions/checkout@34e114876b0b11c390a56381ad16ebd13914f8d5 # v4.3.1
 
@@ -27,22 +16,25 @@ jobs:
         with:
           cache: true
           experimental: true
-          install_args: python@${{ inputs.python-version }} uv
+          install_args: uv
 
       - name: Install dependencies
+        working-directory: integrations/langchain-py
         run: |
-          mise exec python@${{ inputs.python-version }} -- uv sync
+          mise exec -- uv sync
 
-      - name: Lint with ruff
-        if: ${{ inputs.os == 'ubuntu-latest' }}
+      - name: Lint package
+        working-directory: integrations/langchain-py
         run: |
-          mise exec python@${{ inputs.python-version }} -- uv run ruff check $(git ls-files '*.py' | grep -v 'examples/')
+          mise exec -- uv run ruff check $(git ls-files '*.py' | grep -v 'examples/')
 
       - name: Run tests
+        working-directory: integrations/langchain-py
         run: |
-          mise exec python@${{ inputs.python-version }} -- uv run pytest src
+          mise exec -- uv run pytest src
 
-      - name: Test import
+      - name: Test package import
+        working-directory: integrations/langchain-py
         run: |
-          mise exec python@${{ inputs.python-version }} -- uv run python -c "import braintrust_langchain; print('braintrust_langchain imported successfully')"
-          mise exec python@${{ inputs.python-version }} -- uv run python -c "from braintrust_langchain import BraintrustCallbackHandler; print('BraintrustCallbackHandler imported successfully')"
+          mise exec -- uv run python -c "import braintrust_langchain; print('braintrust_langchain imported successfully')"
+          mise exec -- uv run python -c "from braintrust_langchain import BraintrustCallbackHandler; print('BraintrustCallbackHandler imported successfully')"

integrations/langchain-py/pyproject.toml

@@ -42,6 +42,9 @@ members = [
     ".",
 ]
 
+[tool.uv.sources]
+braintrust = { path = "../../py", editable = true }
+
 [dependency-groups]
 dev = [
     "build",

integrations/langchain-py/src/braintrust_langchain/__init__.py

@@ -1,4 +1,24 @@
-from .callbacks import BraintrustCallbackHandler
-from .context import set_global_handler
+"""
+DEPRECATED: braintrust-langchain is now part of the main braintrust package.
+
+Install `braintrust` and use `from braintrust.integrations.langchain import BraintrustCallbackHandler` instead.
+This package now re-exports from `braintrust.integrations.langchain` for backward compatibility.
+"""
+
+import warnings
+
+warnings.warn(
+    "braintrust-langchain is deprecated. The LangChain integration is now included in the main "
+    "'braintrust' package. Use 'from braintrust.integrations.langchain import BraintrustCallbackHandler' "
+    "instead. This package will be removed in a future release.",
+    DeprecationWarning,
+    stacklevel=2,
+)
+
+# Re-export public API from the new location for backward compatibility
+from braintrust.integrations.langchain import (  # noqa: E402, F401
+    BraintrustCallbackHandler,
+    set_global_handler,
+)
 
 __all__ = ["BraintrustCallbackHandler", "set_global_handler"]

integrations/langchain-py/src/tests/conftest.py

@@ -2,6 +2,7 @@
 import os
 
 import pytest
+from braintrust.integrations.langchain.context import clear_global_handler
 from braintrust.logger import (
     TEST_API_KEY,
     Logger,
@@ -11,8 +12,6 @@
 )
 from braintrust.test_helpers import init_test_logger
 
-from braintrust_langchain.context import clear_global_handler
-
 
 @pytest.fixture(autouse=True)
 def setup_braintrust():

integrations/langchain-py/src/tests/test_compat.py

@@ -0,0 +1,28 @@
+"""Test that braintrust_langchain re-exports the public API from braintrust.integrations.langchain."""
+
+import importlib
+import warnings
+
+import pytest
+
+
+def test_public_api_reexported():
+    """All public API symbols should be importable from braintrust_langchain."""
+    with warnings.catch_warnings():
+        warnings.simplefilter("ignore", DeprecationWarning)
+
+        from braintrust_langchain import (
+            BraintrustCallbackHandler,
+            set_global_handler,
+        )
+
+    assert callable(BraintrustCallbackHandler)
+    assert callable(set_global_handler)
+
+
+def test_deprecation_warning():
+    """Importing braintrust_langchain should emit a DeprecationWarning."""
+    import braintrust_langchain
+
+    with pytest.warns(DeprecationWarning, match="braintrust-langchain is deprecated"):
+        importlib.reload(braintrust_langchain)