Second wave of #972 — reproducer on a 37.5 MB BambuStudio print to an A1
showed three stacking root causes when Bambuddy restarts mid-print.
1. Archive start_time lost on container restart. The name-based dedup
cancelled any "printing" archive older than 4h and recreated it with
started_at=now(), so a 13h print that saw a restart 10h in ended up
showing ~1.5h duration. Persist MQTT subtask_id on every archive and
match on that first, regardless of age — same id means same print,
resume in place. Also revives Stale-cancelled rows for users
upgrading mid-print.
2. 3MF FTP search tried non-existent paths for ~48 min. Order was
/cache → /model → /data → /data/Metadata → / with 11×30s retries
each; BambuStudio actually pushes to / on A1, so the real path was
tested last. Reorder to / first, and raise a new FileNotOnPrinterError
sentinel from download_to_file on 550 so with_ftp_retry short-circuits
via non_retry_exceptions. 425 / SSL EOF / connection resets still
retry as before.
3. Cover endpoint and archive flow downloaded the same 36 MB twice and
competed for the printer's single FTP socket, producing 425 errors
that fed cause-2's retry storm. Add an in-memory _threemf_path_cache
keyed on (printer_id, normalized filename); whichever flow fetches
first populates it, the other reuses the file read-only. Eviction
runs on on_print_complete and deletes the temp file.
Backend: 14 new tests across test_bambu_ftp.py and a new
test_subtask_archive_resume.py. Existing suite: 2737 pass. ruff clean,
frontend build clean.
Two-part root cause for missing photos/filament/cost on large prints
(#972). The configured ftp_timeout was only plumbed through as the FTP
socket timeout; the asyncio.wait_for wrapping run_in_executor stayed on
its 60s hardcoded default, so the user's 300s setting never applied.
Worse, asyncio.wait_for cannot cancel run_in_executor threads — after
the 60s outer timeout fired, the executor thread kept running
ftplib.retrbinary and frequently completed the download ~30–60s later,
but by then the async wrapper had returned False. with_ftp_retry kept
re-attempting the same path, each retry truncating the file the zombie
thread had just written, and the archive was ultimately persisted as a
fallback with no 3MF.
download_file_async now accepts timeout at each call site (plumbed from
ftp_timeout) and salvages post-timeout success via an explicit
completion flag the executor thread sets only after download_to_file
returns True. Per-attempt completion dict so a prot_p zombie can't
flip the flag for a later prot_c attempt. A cosmetic // prefix in the
directory-search download path is also fixed by replacing string
concatenation with posixpath.join.
FTP upload: reduce chunk size from 1MB to 64KB for smooth progress bar
updates (~1s intervals instead of 20+ second gaps). Skip voidresp() for
all printer models — H2D delays the 226 response by 30+ seconds after
data transfer, causing a hang at 100%. Add transfer speed and TLS
handshake timing to logs for diagnosing slow connections.
Print/Schedule modal: widen from max-w-lg (512px) to max-w-2xl (672px)
to accommodate long filament profile names like "PLA Support for PETG
PETG Basic @Bambu Lab H2D 0.4 nozzle".
This allows users sending particularly large prints to slow printers such as the P1-series to start a print and then move onto another task in Bambuddy immediately (such as starting more prints on more printers). It also gives the user visibility into what's happening instead of a loading indicator appearing for an indefinite period of time.
The new toast-based UI uses websockets to update in real time. It will also appear for other users / instances of Bambuddy, not just the user who started the prints, allowing more transparency and handling cases where the user closes the page and then comes back wanting to know the status of the dispatching.
fix: review fixes for background dispatch PR #408
- Restore missing imports in main.py (inventory, print_log, virtual_printers, mqtt_smart_plug_service)
- Guard voidresp() for A1 printers to prevent hang after upload
- Don't fail upload on voidresp() error since data transfer already completed
- Add ams_mapping to register_expected_print calls for Spoolman usage tracking
- Fix cancel_job TOCTOU race by using single lock acquisition
- Fix batch counter reset TOCTOU by re-checking condition inside second lock
- Add backgroundDispatch translations to fr.ts and pt-BR.ts
- Remove dead upload_progress_callback definitions
- Skip redundant "Print queued" toast in reprint mode (dispatch toast handles it)
- 5 backend tests: cancel_job single-lock TOCTOU, batch reset re-check,
job lifecycle
- 2 FTP regression tests: voidresp error handling (upload-loop fix),
A1 model voidresp skip
- 1 frontend test: reprint toast suppression
- CHANGELOG: background dispatch feature + test coverage entries
- README: add background dispatch to Scheduling & Automation
- Website: add feature item to Automation section
- Wiki: add Background Print Dispatch section to print-queue.md
Dual-nozzle H2D/H2D Pro: filament matching now respects nozzle assignments
from the 3MF file. Each AMS unit feeds a specific nozzle (L/R), and the
scheduler/frontend constrain matching to only trays on the correct nozzle.
Falls back to unfiltered matching when no trays exist on the target nozzle.
L/R badges shown in the filament mapping UI. Translated in en/de/ja/it.
Fix AMS slot config overwritten on startup: on_ams_change unconditionally
unlinked BL spool assignments on every MQTT pushall, then re-assigned them
sending ams_filament_setting without setting_id — clearing the printer's
filament preset. Now compares spool RFID identifiers before unlinking.
Fix BL spool detection false positives: removed tray_info_idx from detection
logic in both backend is_bambu_lab_spool() and frontend isBambuLabSpool().
Third-party spools using Bambu generic presets had GF-prefixed tray_info_idx
values, causing misidentification. Now uses only tray_uuid and tag_uid.
SQLite WAL mode with 5s busy timeout reduces "database is locked" errors.
Function-scoped ftp_server meant 67 TLS server start/stop cycles.
Class-scoped reduces to 10. Adds per-test cleanup fixture to reset
failure injections and filesystem between tests. Isolates
test_disconnect_after_server_gone into its own class to prevent
close_all() from nuking other servers' asyncore sockets.
FTP bugs have been the #1 recurring issue across releases (0.1.8+).
This adds a real implicit FTPS mock server and 67 test cases covering
every known failure mode — connection, upload, download, delete, storage
info, model-specific SSL behavior, async wrappers, and failure injection.
New files:
- mock_ftp_server.py: implicit FTPS server on pyftpdlib with failure injection
- conftest.py: FTP test fixtures (certs, server, client factory)
- test_bambu_ftp.py: 67 tests across 10 test classes
Also adds pyOpenSSL to requirements-dev.txt (needed by pyftpdlib
TLS_FTPHandler in the Docker test image).