HLS validation tests (Python)

This suite validates lazy transcoding behavior with a focus on:

timeline continuity (no gaps, no repeated/overlapping playback windows)
real playback patterns (sequential, ABR switches, seeks, concurrent clients)

It is segment-container agnostic and does not assume .ts segments. Segment URLs are read from playlists and probed with ffprobe regardless of extension.

Requirements

Python 3.11+
ffprobe available in $PATH (from FFmpeg)
A running transcoder service
A playable media file available under transcoder GOCODER_SAFE_PATH

Install Python deps:

uv pip install -r transcoder/tests/hls_validation/requirements.txt

Environment variables

TRANSCODER_BASE_URL (default: http://localhost:7666/video)
TRANSCODER_MEDIA_PATH (required): absolute media path as seen by transcoder (example: /video/movies/demo.mkv)
TRANSCODER_CLIENT_ID_PREFIX (default: hls-test)
TRANSCODER_MAX_SEGMENTS (default: 14)
TRANSCODER_MAX_VARIANT_PLAYLISTS (default: 3)
TRANSCODER_MAX_AUDIO_PLAYLISTS (default: 2)
TRANSCODER_TIMEOUT_SECONDS (default: 40)
TRANSCODER_API_KEY (optional): if set, sent as X-Api-Key header for all requests

For your current setup with docker-compose.dev.yml, set TRANSCODER_API_KEY=admin.

Run

pytest transcoder/tests/hls_validation -q

For docker-compose.dev.yml with API key auth via Traefik:

TRANSCODER_BASE_URL="http://localhost:8901/video" \
TRANSCODER_MEDIA_PATH="/video/The legend of korra S04E05.mkv" \
TRANSCODER_API_KEY="admin" \
uv run --with pytest pytest transcoder/tests/hls_validation -q