From 482c168b3e8ac982130bacc89fc9a32b67f765a3 Mon Sep 17 00:00:00 2001
From: takahashi <7567050+MasaYan24@users.noreply.github.com>
Date: Thu, 7 Nov 2024 07:37:07 +0900
Subject: [PATCH] langchain_core: add `file_type` option to make file type
 default as `png` (#27855)

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- Where "package" is whichever of langchain, community, core, etc. is
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..." for template changes, "infra: ..." for CI changes.
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- [ ] **description**
langchain_core.runnables.graph_mermaid.draw_mermaid_png calls this
function, but the Mermaid API returns JPEG by default. To be consistent,
add the option `file_type` with the default `png` type.

- [ ] **Add tests and docs**: If you're adding a new integration, please
include
With this small change, I didn't add tests and docs.

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from the root of the package(s) you've modified. See contribution
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One long sentence was divided into two.

Additional guidelines:
- Make sure optional dependencies are imported within a function.
- Please do not add dependencies to pyproject.toml files (even optional
ones) unless they are required for unit tests.
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- Changes should be backwards compatible.
- If you are adding something to community, do not re-import it in
langchain.

If no one reviews your PR within a few days, please @-mention one of
baskaryan, efriis, eyurtsev, ccurme, vbarda, hwchase17.
---
 libs/core/langchain_core/runnables/graph_mermaid.py | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/libs/core/langchain_core/runnables/graph_mermaid.py b/libs/core/langchain_core/runnables/graph_mermaid.py
index b0e7f3dd5de..c9b3025bc85 100644
--- a/libs/core/langchain_core/runnables/graph_mermaid.py
+++ b/libs/core/langchain_core/runnables/graph_mermaid.py
@@ -2,7 +2,7 @@ import asyncio
 import base64
 import re
 from dataclasses import asdict
-from typing import Optional
+from typing import Literal, Optional
 
 from langchain_core.runnables.graph import (
     CurveStyle,
@@ -306,6 +306,7 @@ def _render_mermaid_using_api(
     mermaid_syntax: str,
     output_file_path: Optional[str] = None,
     background_color: Optional[str] = "white",
+    file_type: Optional[Literal["jpeg", "png", "webp"]] = "png",
 ) -> bytes:
     """Renders Mermaid graph using the Mermaid.INK API."""
     try:
@@ -329,7 +330,8 @@ def _render_mermaid_using_api(
             background_color = f"!{background_color}"
 
     image_url = (
-        f"https://mermaid.ink/img/{mermaid_syntax_encoded}?bgColor={background_color}"
+        f"https://mermaid.ink/img/{mermaid_syntax_encoded}"
+        f"?type={file_type}&bgColor={background_color}"
     )
     response = requests.get(image_url, timeout=10)
     if response.status_code == 200: