upload_audio() could only sign a URL when GCP_CREDENTIALS_PATH pointed at a
service-account key file. The deployed VM runs on Application Default
Credentials with no key file, so every upload silently took the fallback
branch and returned a bare gs:// URI. That broke two things at once:
* Browsers cannot fetch a gs:// URI, so no recording was ever playable.
* _public_url_to_gcs_uri() only matched https://storage.googleapis.com/ and
returned None for it, so `if gcs_uri:` in the upload path was always false
and transcription never ran. Nothing was logged, which is why this looked
like an OpenAI credits problem rather than a storage one.
The fallback also interpolated the client-supplied filename instead of the
call_id-derived safe name, so the URI did not even name the object written.
Calls now store only the canonical gs:// location. A short-lived playback link
is minted per read as an HMAC over (call_id, expiry) keyed by SERVICE_KEY, and
audio is served from the private bucket by the new /media route. An <audio src>
cannot carry an Authorization header, so the link has to be the credential;
that router is therefore public with the check done inline, as enrollment.py
already does. Signing GCS URLs from the VM would have needed a
serviceAccountTokenCreator grant on its own service account — this avoids the
IAM change entirely and keeps the bucket private.
gcs_uri_for_call() reconstructs the object name from call_id, so recordings
made before this fix are reachable again without a data migration.
Frontend rows come straight from Firestore via onSnapshot and never see a
server-minted field, so CallRow fetches the link lazily on expand.
Also removes the last long-lived (1 year) signed URL and the log line that
printed it.
auth.py
secrets.compare_digest replaces == for service key comparison (timing-safe)
Added require_service_key — bot-only endpoints (trip/event join/leave)
Added require_service_key_or_admin — node commands/config (bot via service key OR dashboard admin via Firebase)
Added _RateLimiter with three shared instances: trip_chat_limiter (20/5min per user), summarize_limiter (5/10min per incident), bootstrap_limiter (2/hr per system)
nodes.py
send_command and assign_system now require require_service_key_or_admin — the Discord bot can still call them via service key, but regular Firebase users are blocked
tokens.py
add_token, flush_tokens, set_preferred_system, delete_token all require require_admin_token
Token masking changed from token[:10] + "…" + token[-4:] to "•••" + token[-4:]
systems.py
All write endpoints (create, update, delete, ai-flags, ten-codes, vocabulary writes, bootstrap) now require require_admin_token
bootstrap_vocabulary also calls bootstrap_limiter.check(system_id)
incidents.py
POST /incidents/summarize (bulk) now requires require_admin_token
POST /incidents/{id}/summarize now calls summarize_limiter.check(incident_id)
trips.py
join_trip, leave_trip, join_event, leave_event require require_service_key — only the Discord bot can set Discord attendee identity
delete_trip, delete_event require require_service_key_or_admin
trip_chat rate-limited per caller UID, history stripped to user/assistant roles only, user message truncated to 2000 chars, Maps query strings capped at 200 chars
upload.py
Rejects files larger than settings.upload_max_bytes (default 100MB) with 413
storage.py
_safe_audio_filename() derives GCS object name from call_id + allowlisted extension, completely ignoring the client-supplied filename
config.py
Added upload_max_bytes: int = 100 * 1024 * 1024
Both Dockerfiles — python:3.14-slim → python:3.12-slim
app/internal/storage.py Replaced make_public() + public_url with a v2 signed URL (1-year expiry, no public bucket needed)
app/main.py Releases all in-use tokens at startup — tokens from previous sessions are cleared automatically
app/routers/tokens.py Added POST /tokens/flush to force-release orphaned tokens on demand
docker-compose.yml: Added a pulse_socket named volume mounted at /run/pulse in both op25 and edge-node. Also set PULSE_SERVER=unix:/run/pulse/native in edge-node so libpulse (and ffmpeg's pulse input) finds the right socket.
discord_radio.py: Removed _icecast_url and changed _play_stream() to use -f pulse -i default.monitor. This reads directly from the PulseAudio sink monitor — zero buffer delay. The PULSE_SERVER env var is inherited by the ffmpeg subprocess.
Note: default.monitor captures whatever audio is playing on the default sink. If OP25 uses a named virtual sink, you may need to replace default.monitor with <sink_name>.monitor (run pactl list sinks short inside the op25 container to find the name).
Issue 2 — No audio URL / GCS credentials
storage.py: storage.Client() was using ADC but ADC isn't configured in the container. Now uses storage.Client.from_service_account_json(settings.gcp_credentials_path) when GCP_CREDENTIALS_PATH is set — same credential file Firebase already loads.
You also need to mount the key file into the server container in docker-compose.yml:
c2-core:
volumes:
- ./gcp-key.json:/app/gcp-key.json:ro
And set GCS_BUCKET=your-bucket-name in .env.
Issue 3 — Token orphaning
mqtt_manager.py: Every checkin now includes "discord_connected": radio_bot.is_connected.
mqtt_handler.py: On checkin, if discord_connected is explicitly False, calls release_token(node_id). Only fires on explicit false (missing field = unknown = no action).
node_sweeper.py: When a node is swept to offline, its token is released too. This covers the case where the node stops checking in entirely (crash/power loss).
Logan Cusano