fix: handle inf/nan float values in JSON serialization

[r266-tech]

Fixes #871

Problem

OpenViking server crashes with ValueError: Out of range float values are not JSON compliant: inf when vector similarity calculations produce infinity values.

Root Cause

FastAPI's default JSONResponse uses json.dumps which raises ValueError when encountering inf or nan float values, as these are not valid JSON.

Fix

1. Added _sanitize_floats() helper that recursively replaces inf/nan with None
2. Added SafeJSONResponse class that sanitizes content before JSON serialization
3. Updated both exception handlers in app.py to use SafeJSONResponse

This ensures the server never crashes due to non-JSON-compliant float values, whether in normal responses or error responses.

Changes

• 1 file changed, 28 insertions(+), 2 deletions(-)
• openviking/server/app.py

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[github-actions]

Failed to generate code suggestions for PR

[qin-ctx]

Thanks for the fix! 🙏

#882 has already been merged, which addresses the same issue (#871) by clamping inf/nan scores at the source (adapter and retriever layers). This way search results are returned correctly instead of falling through to an error response.

Since the root cause is now handled upstream, this PR is no longer needed. Going to close it — thanks again for jumping on this!