init

libs/core/langchain_core/messages/base.py

@@ -211,6 +211,9 @@ class BaseMessage(Serializable):
         from langchain_core.messages.block_translators.google_genai import (  # noqa: PLC0415
             _convert_to_v1_from_genai_input,
         )
+        from langchain_core.messages.block_translators.google_vertexai import (  # noqa: PLC0415
+            _convert_to_v1_from_vertexai_input,
+        )
         from langchain_core.messages.block_translators.langchain_v0 import (  # noqa: PLC0415
             _convert_v0_multimodal_input_to_v1,
         )
@@ -252,6 +255,7 @@ class BaseMessage(Serializable):
             _convert_to_v1_from_chat_completions_input,
             _convert_to_v1_from_anthropic_input,
             _convert_to_v1_from_genai_input,
+            _convert_to_v1_from_vertexai_input,
             _convert_to_v1_from_converse_input,
         ]:
             blocks = parsing_step(blocks)

libs/core/langchain_core/messages/block_translators/google_vertexai.py

@@ -1,6 +1,7 @@
 """Derivations of standard content blocks from Google (VertexAI) content."""
 
-import warnings
+from collections.abc import Iterable
+from typing import Any, cast
 
 from langchain_core.messages import AIMessage, AIMessageChunk
 from langchain_core.messages import content as types
@@ -8,30 +9,97 @@ from langchain_core.messages import content as types
 WARNED = False
 
 
-def translate_content(message: AIMessage) -> list[types.ContentBlock]:  # noqa: ARG001
+def _convert_to_v1_from_vertexai_input(
+    content: list[types.ContentBlock],
+) -> list[types.ContentBlock]:
+    """Convert Google (VertexAI) format blocks to v1 format.
+
+    Called when message isn't an `AIMessage` or `model_provider` isn't set on
+    `response_metadata`.
+
+    During the `.content_blocks` parsing process, we wrap blocks not recognized as a v1
+    block as a ``'non_standard'`` block with the original block stored in the ``value``
+    field. This function attempts to unpack those blocks and convert any blocks that
+    might be GenAI format to v1 ContentBlocks.
+
+    If conversion fails, the block is left as a ``'non_standard'`` block.
+
+    Args:
+        content: List of content blocks to process.
+
+    Returns:
+        Updated list with VertexAI blocks converted to v1 format.
+    """
+
+    def _iter_blocks() -> Iterable[types.ContentBlock]:
+        blocks: list[dict[str, Any]] = [
+            cast("dict[str, Any]", block)
+            if block.get("type") != "non_standard"
+            else block["value"]  # type: ignore[typeddict-item]  # this is only non-standard blocks
+            for block in content
+        ]
+        for block in blocks:
+            num_keys = len(block)
+
+            if num_keys == 1 and (text := block.get("text")):
+                # This is probably a TextContentBlock
+                yield {"type": "text", "text": text}
+
+            elif (
+                num_keys == 1
+                and (document := block.get("document"))
+                and isinstance(document, dict)
+                and "format" in document
+            ):
+                # Probably a document of some kind - TODO
+                yield {"type": "non_standard", "value": block}
+
+            elif (
+                num_keys == 1
+                and (image := block.get("image"))
+                and isinstance(image, dict)
+                and "format" in image
+            ):
+                # Probably an image of some kind - TODO
+                yield {"type": "non_standard", "value": block}
+
+            elif block.get("type") in types.KNOWN_BLOCK_TYPES:
+                # We see a standard block type, so we just cast it, even if
+                # we don't fully understand it. This may be dangerous, but
+                # it's better than losing information.
+                yield cast("types.ContentBlock", block)
+
+            else:
+                # We don't understand this block at all.
+                yield {"type": "non_standard", "value": block}
+
+    return list(_iter_blocks())
+
+
+def _convert_to_v1_from_vertexai(message: AIMessage) -> list[types.ContentBlock]:
+    """Convert Google (VertexAI) message content to v1 format.
+
+    Calling `.content_blocks` on an `AIMessage` where `response_metadata.model_provider`
+    is set to `'google_vertexai'` will invoke this function to parse the content into
+    standard content blocks for returning.
+
+    Args:
+        message: The AIMessage or AIMessageChunk to convert.
+
+    Returns:
+        List of standard content blocks derived from the message content.
+    """
+    return message  # type: ignore[return-value]
+
+
+def translate_content(message: AIMessage) -> list[types.ContentBlock]:
     """Derive standard content blocks from a message with Google (VertexAI) content."""
-    global WARNED  # noqa: PLW0603
-    if not WARNED:
-        warning_message = (
-            "Content block standardization is not yet fully supported for Google "
-            "VertexAI."
-        )
-        warnings.warn(warning_message, stacklevel=2)
-        WARNED = True
-    raise NotImplementedError
+    return _convert_to_v1_from_vertexai(message)
 
 
-def translate_content_chunk(message: AIMessageChunk) -> list[types.ContentBlock]:  # noqa: ARG001
+def translate_content_chunk(message: AIMessageChunk) -> list[types.ContentBlock]:
     """Derive standard content blocks from a chunk with Google (VertexAI) content."""
-    global WARNED  # noqa: PLW0603
-    if not WARNED:
-        warning_message = (
-            "Content block standardization is not yet fully supported for Google "
-            "VertexAI."
-        )
-        warnings.warn(warning_message, stacklevel=2)
-        WARNED = True
-    raise NotImplementedError
+    return _convert_to_v1_from_vertexai(message)
 
 
 def _register_google_vertexai_translator() -> None: