infra: add min version testing to pr test flow (#24358)

xfailing some sql tests that do not currently work on sqlalchemy v1

#22207 was very much not sqlalchemy v1 compatible. 

Moving forward, implementations should be compatible with both to pass
CI

Author: Erick Friis

.github/scripts/get_min_versions.py

@@ -1,6 +1,11 @@
 import sys
 
-import tomllib
+if sys.version_info >= (3, 11):
+    import tomllib
+else:
+    # for python 3.10 and below, which doesnt have stdlib tomllib
+    import tomli as tomllib
+
 from packaging.version import parse as parse_version
 import re
 

.github/workflows/_test.yml

@@ -65,3 +65,21 @@ jobs:
           # grep will exit non-zero if the target message isn't found,
           # and `set -e` above will cause the step to fail.
           echo "$STATUS" | grep 'nothing to commit, working tree clean'
+          
+      - name: Get minimum versions
+        working-directory: ${{ inputs.working-directory }}
+        id: min-version
+        run: |
+          poetry run pip install packaging tomli
+          min_versions="$(poetry run python $GITHUB_WORKSPACE/.github/scripts/get_min_versions.py pyproject.toml)"
+          echo "min-versions=$min_versions" >> "$GITHUB_OUTPUT"
+          echo "min-versions=$min_versions"
+
+      - name: Run unit tests with minimum dependency versions
+        if: ${{ steps.min-version.outputs.min-versions != '' }}
+        env:
+          MIN_VERSIONS: ${{ steps.min-version.outputs.min-versions }}
+        run: |
+          poetry run pip install --force-reinstall $MIN_VERSIONS --editable .
+          make tests
+        working-directory: ${{ inputs.working-directory }}

libs/community/langchain_community/chat_message_histories/sql.py

@@ -32,7 +32,6 @@
 from sqlalchemy.ext.asyncio import (
     AsyncEngine,
     AsyncSession,
-    async_sessionmaker,
     create_async_engine,
 )
 from sqlalchemy.orm import (
@@ -44,6 +43,12 @@
     sessionmaker,
 )
 
+try:
+    from sqlalchemy.ext.asyncio import async_sessionmaker
+except ImportError:
+    # dummy for sqlalchemy < 2
+    async_sessionmaker = type("async_sessionmaker", (type,), {})  # type: ignore
+
 logger = logging.getLogger(__name__)
 
 

libs/community/langchain_community/storage/sql.py

@@ -17,46 +17,72 @@
 
 from langchain_core.stores import BaseStore
 from sqlalchemy import (
-    Engine,
     LargeBinary,
+    Text,
     and_,
     create_engine,
     delete,
     select,
 )
+from sqlalchemy.engine.base import Engine
 from sqlalchemy.ext.asyncio import (
     AsyncEngine,
     AsyncSession,
-    async_sessionmaker,
     create_async_engine,
 )
 from sqlalchemy.orm import (
     Mapped,
     Session,
     declarative_base,
-    mapped_column,
     sessionmaker,
 )
 
+try:
+    from sqlalchemy.ext.asyncio import async_sessionmaker
+except ImportError:
+    # dummy for sqlalchemy < 2
+    async_sessionmaker = type("async_sessionmaker", (type,), {})  # type: ignore
+
 Base = declarative_base()
 
+try:
+    from sqlalchemy.orm import mapped_column
 
-def items_equal(x: Any, y: Any) -> bool:
-    return x == y
+    class LangchainKeyValueStores(Base):  # type: ignore[valid-type,misc]
+        """Table used to save values."""
+
+        # ATTENTION:
+        # Prior to modifying this table, please determine whether
+        # we should create migrations for this table to make sure
+        # users do not experience data loss.
+        __tablename__ = "langchain_key_value_stores"
+
+        namespace: Mapped[str] = mapped_column(
+            primary_key=True, index=True, nullable=False
+        )
+        key: Mapped[str] = mapped_column(primary_key=True, index=True, nullable=False)
+        value = mapped_column(LargeBinary, index=False, nullable=False)
+
+except ImportError:
+    # dummy for sqlalchemy < 2
+    from sqlalchemy import Column
+
+    class LangchainKeyValueStores(Base):  # type: ignore[valid-type,misc,no-redef]
+        """Table used to save values."""
 
+        # ATTENTION:
+        # Prior to modifying this table, please determine whether
+        # we should create migrations for this table to make sure
+        # users do not experience data loss.
+        __tablename__ = "langchain_key_value_stores"
 
-class LangchainKeyValueStores(Base):  # type: ignore[valid-type,misc]
-    """Table used to save values."""
+        namespace = Column(Text(), primary_key=True, index=True, nullable=False)
+        key = Column(Text(), primary_key=True, index=True, nullable=False)
+        value = Column(LargeBinary, index=False, nullable=False)
 
-    # ATTENTION:
-    # Prior to modifying this table, please determine whether
-    # we should create migrations for this table to make sure
-    # users do not experience data loss.
-    __tablename__ = "langchain_key_value_stores"
 
-    namespace: Mapped[str] = mapped_column(primary_key=True, index=True, nullable=False)
-    key: Mapped[str] = mapped_column(primary_key=True, index=True, nullable=False)
-    value = mapped_column(LargeBinary, index=False, nullable=False)
+def items_equal(x: Any, y: Any) -> bool:
+    return x == y
 
 
 # This is a fix of original SQLStore.
@@ -135,7 +161,10 @@ def __init__(
         self.namespace = namespace
 
     def create_schema(self) -> None:
-        Base.metadata.create_all(self.engine)
+        Base.metadata.create_all(self.engine)  # problem in sqlalchemy v1
+        # sqlalchemy.exc.CompileError: (in table 'langchain_key_value_stores',
+        # column 'namespace'): Can't generate DDL for NullType(); did you forget
+        # to specify a type on this Column?
 
     async def acreate_schema(self) -> None:
         assert isinstance(self.engine, AsyncEngine)

libs/community/langchain_community/utilities/sql_database.py

@@ -338,7 +338,7 @@ def get_table_info(self, table_names: Optional[List[str]] = None) -> str:
                 continue
 
             # Ignore JSON datatyped columns
-            for k, v in table.columns.items():
+            for k, v in table.columns.items():  # AttributeError: items in sqlalchemy v1
                 if type(v.type) is NullType:
                     table._columns.remove(v)
 

libs/community/tests/unit_tests/storage/test_sql.py

@@ -1,12 +1,16 @@
 from typing import AsyncGenerator, Generator, cast
 
 import pytest
+import sqlalchemy as sa
 from langchain.storage._lc_store import create_kv_docstore, create_lc_store
 from langchain_core.documents import Document
 from langchain_core.stores import BaseStore
+from packaging import version
 
 from langchain_community.storage.sql import SQLStore
 
+is_sqlalchemy_v1 = version.parse(sa.__version__).major == 1
+
 
 @pytest.fixture
 def sql_store() -> Generator[SQLStore, None, None]:
@@ -22,6 +26,7 @@ async def async_sql_store() -> AsyncGenerator[SQLStore, None]:
     yield store
 
 
+@pytest.mark.xfail(is_sqlalchemy_v1, reason="SQLAlchemy 1.x issues")
 def test_create_lc_store(sql_store: SQLStore) -> None:
     """Test that a docstore is created from a base store."""
     docstore: BaseStore[str, Document] = cast(
@@ -34,6 +39,7 @@ def test_create_lc_store(sql_store: SQLStore) -> None:
     assert fetched_doc.metadata == {"key": "value"}
 
 
+@pytest.mark.xfail(is_sqlalchemy_v1, reason="SQLAlchemy 1.x issues")
 def test_create_kv_store(sql_store: SQLStore) -> None:
     """Test that a docstore is created from a base store."""
     docstore = create_kv_docstore(sql_store)
@@ -57,6 +63,7 @@ async def test_async_create_kv_store(async_sql_store: SQLStore) -> None:
     assert fetched_doc.metadata == {"key": "value"}
 
 
+@pytest.mark.xfail(is_sqlalchemy_v1, reason="SQLAlchemy 1.x issues")
 def test_sample_sql_docstore(sql_store: SQLStore) -> None:
     # Set values for keys
     sql_store.mset([("key1", b"value1"), ("key2", b"value2")])

libs/community/tests/unit_tests/test_sql_database.py

@@ -55,6 +55,7 @@ def db_lazy_reflection(engine: Engine) -> SQLDatabase:
     return SQLDatabase(engine, lazy_table_reflection=True)
 
 
+@pytest.mark.xfail(is_sqlalchemy_v1, reason="SQLAlchemy 1.x issues")
 def test_table_info(db: SQLDatabase) -> None:
     """Test that table info is constructed properly."""
     output = db.table_info
@@ -85,6 +86,7 @@ def test_table_info(db: SQLDatabase) -> None:
     assert sorted(" ".join(output.split())) == sorted(" ".join(expected_output.split()))
 
 
+@pytest.mark.xfail(is_sqlalchemy_v1, reason="SQLAlchemy 1.x issues")
 def test_table_info_lazy_reflection(db_lazy_reflection: SQLDatabase) -> None:
     """Test that table info with lazy reflection"""
     assert len(db_lazy_reflection._metadata.sorted_tables) == 0
@@ -111,6 +113,7 @@ def test_table_info_lazy_reflection(db_lazy_reflection: SQLDatabase) -> None:
     assert db_lazy_reflection._metadata.sorted_tables[1].name == "user"
 
 
+@pytest.mark.xfail(is_sqlalchemy_v1, reason="SQLAlchemy 1.x issues")
 def test_table_info_w_sample_rows(db: SQLDatabase) -> None:
     """Test that table info is constructed properly."""
 

libs/community/tests/unit_tests/test_sql_database_schema.py

@@ -18,6 +18,9 @@
     insert,
     schema,
 )
+import sqlalchemy as sa
+
+from packaging import version
 
 from langchain_community.utilities.sql_database import SQLDatabase
 
@@ -43,6 +46,9 @@
 )
 
 
+@pytest.mark.xfail(
+    version.parse(sa.__version__).major == 1, reason="SQLAlchemy 1.x issues"
+)
 def test_table_info() -> None:
     """Test that table info is constructed properly."""
     engine = create_engine("duckdb:///:memory:")
@@ -65,6 +71,9 @@ def test_table_info() -> None:
     assert sorted(" ".join(output.split())) == sorted(" ".join(expected_output.split()))
 
 
+@pytest.mark.xfail(
+    version.parse(sa.__version__).major == 1, reason="SQLAlchemy 1.x issues"
+)
 def test_sql_database_run() -> None:
     """Test that commands can be run successfully and returned in correct format."""
     engine = create_engine("duckdb:///:memory:")