multiple: langchain 0.2 in master (#21191)

0.2rc 

migrations

- [x] Move memory
- [x] Move remaining retrievers
- [x] graph_qa chains
- [x] some dependency from evaluation code potentially on math utils
- [x] Move openapi chain from `langchain.chains.api.openapi` to
`langchain_community.chains.openapi`
- [x] Migrate `langchain.chains.ernie_functions` to
`langchain_community.chains.ernie_functions`
- [x] migrate `langchain/chains/llm_requests.py` to
`langchain_community.chains.llm_requests`
- [x] Moving `langchain_community.cross_enoders.base:BaseCrossEncoder`
->
`langchain_community.retrievers.document_compressors.cross_encoder:BaseCrossEncoder`
(namespace not ideal, but it needs to be moved to `langchain` to avoid
circular deps)
- [x] unit tests langchain -- add pytest.mark.community to some unit
tests that will stay in langchain
- [x] unit tests community -- move unit tests that depend on community
to community
- [x] mv integration tests that depend on community to community
- [x] mypy checks

Other todo

- [x] Make deprecation warnings not noisy (need to use warn deprecated
and check that things are implemented properly)
- [x] Update deprecation messages with timeline for code removal (likely
we actually won't be removing things until 0.4 release) -- will give
people more time to transition their code.
- [ ] Add information to deprecation warning to show users how to
migrate their code base using langchain-cli
- [ ] Remove any unnecessary requirements in langchain (e.g., is
SQLALchemy required?)

---------

Co-authored-by: Erick Friis <erick@langchain.dev>

libs/community/langchain_community/query_constructors/qdrant.py

@@ -0,0 +1,98 @@
+from __future__ import annotations
+
+from typing import TYPE_CHECKING, Tuple
+
+from langchain_core.structured_query import (
+    Comparator,
+    Comparison,
+    Operation,
+    Operator,
+    StructuredQuery,
+    Visitor,
+)
+
+if TYPE_CHECKING:
+    from qdrant_client.http import models as rest
+
+
+class QdrantTranslator(Visitor):
+    """Translate `Qdrant` internal query language elements to valid filters."""
+
+    allowed_operators = (
+        Operator.AND,
+        Operator.OR,
+        Operator.NOT,
+    )
+    """Subset of allowed logical operators."""
+
+    allowed_comparators = (
+        Comparator.EQ,
+        Comparator.LT,
+        Comparator.LTE,
+        Comparator.GT,
+        Comparator.GTE,
+        Comparator.LIKE,
+    )
+    """Subset of allowed logical comparators."""
+
+    def __init__(self, metadata_key: str):
+        self.metadata_key = metadata_key
+
+    def visit_operation(self, operation: Operation) -> rest.Filter:
+        try:
+            from qdrant_client.http import models as rest
+        except ImportError as e:
+            raise ImportError(
+                "Cannot import qdrant_client. Please install with `pip install "
+                "qdrant-client`."
+            ) from e
+
+        args = [arg.accept(self) for arg in operation.arguments]
+        operator = {
+            Operator.AND: "must",
+            Operator.OR: "should",
+            Operator.NOT: "must_not",
+        }[operation.operator]
+        return rest.Filter(**{operator: args})
+
+    def visit_comparison(self, comparison: Comparison) -> rest.FieldCondition:
+        try:
+            from qdrant_client.http import models as rest
+        except ImportError as e:
+            raise ImportError(
+                "Cannot import qdrant_client. Please install with `pip install "
+                "qdrant-client`."
+            ) from e
+
+        self._validate_func(comparison.comparator)
+        attribute = self.metadata_key + "." + comparison.attribute
+        if comparison.comparator == Comparator.EQ:
+            return rest.FieldCondition(
+                key=attribute, match=rest.MatchValue(value=comparison.value)
+            )
+        if comparison.comparator == Comparator.LIKE:
+            return rest.FieldCondition(
+                key=attribute, match=rest.MatchText(text=comparison.value)
+            )
+        kwargs = {comparison.comparator.value: comparison.value}
+        return rest.FieldCondition(key=attribute, range=rest.Range(**kwargs))
+
+    def visit_structured_query(
+        self, structured_query: StructuredQuery
+    ) -> Tuple[str, dict]:
+        try:
+            from qdrant_client.http import models as rest
+        except ImportError as e:
+            raise ImportError(
+                "Cannot import qdrant_client. Please install with `pip install "
+                "qdrant-client`."
+            ) from e
+
+        if structured_query.filter is None:
+            kwargs = {}
+        else:
+            filter = structured_query.filter.accept(self)
+            if isinstance(filter, rest.FieldCondition):
+                filter = rest.Filter(must=[filter])
+            kwargs = {"filter": filter}
+        return structured_query.query, kwargs