Harikrishna KP 294dda8df2 test(core): URL-encode bgColor parameter in mermaid.ink API calls (#34466) ...

## Problem

The `draw_mermaid_png()` function fails with HTTP 400 when using named
background colors like `white`. This is because named colors get
prefixed with `!` (e.g., `!white`) but this special character is not
URL-encoded before being added to the API URL.

As reported in #34444, the URL parameter `bgColor=!white` causes
mermaid.ink to return a 400 Bad Request error.

## Solution

URL-encode the `background_color` parameter using `urllib.parse.quote()`
before constructing the API URL. This ensures special characters like
`!` are properly encoded as `%21`.

## Changes

- Added `import urllib.parse` 
- URL-encode `background_color` value with
`urllib.parse.quote(str(background_color), safe="")`
- Added 2 unit tests:
- `test_mermaid_bgcolor_url_encoding`: Verifies named colors are
properly encoded
- `test_mermaid_bgcolor_hex_not_encoded`: Verifies hex colors work
correctly

## Testing

```bash
pytest tests/unit_tests/runnables/test_graph.py::test_mermaid_bgcolor_url_encoding -v
pytest tests/unit_tests/runnables/test_graph.py::test_mermaid_bgcolor_hex_not_encoded -v
```

Both tests pass.

Fixes #34444

---
*This contribution was made with AI assistance (Claude).*

Co-authored-by: Mr-Neutr0n <mrneutron@users.noreply.github.com>
Co-authored-by: Mason Daugherty <mason@langchain.dev>

2025-12-25 21:41:46 -06:00

..

benchmarks

feat: Use uuid7 for run ids (#34172)

2025-12-03 10:09:10 -08:00

integration_tests

core: Add ruff rules for PIE (#26939)

2024-09-27 12:08:35 -04:00

unit_tests

test(core): URL-encode bgColor parameter in mermaid.ink API calls (#34466)

2025-12-25 21:41:46 -06:00

__init__.py

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