Two printers went on printing while every archive they produced held nothing
but a filename. Bambuddy opened port 990, the printer accepted the connection
and answered with something that was not TLS, and connect() logged a warning
and returned False -- indistinguishable, to every caller, from "the file is
not at this path". So the 3MF lookup walked all six filename variants across
five directories with four retries each, the cover endpoint ran its own
sixteen-path sweep, and the timelapse scan added four more, all against a
sixteen-path sweep, and the timelapse scan added four more, all against a
printer that could not have answered any of them. One reporter's log carried
1813 identical handshake failures, another's 3511.
The evidence says this is the printer's own file service getting stuck, not a
model, firmware or TLS-configuration problem. In #2780's bundle the same two
printers ran clean from 22 July to 4 August and failed again from the 5th; a
second bundle shows an X2D serving files for five days, flipping on 19 July,
then failing every connection for eight days with zero successes. The same
models and firmware appear in roughly twenty other bundles with no occurrences
at all. Both bundles show it happening with cap_tls_v1_2 in effect -- the X2D
and H2C entries in ftp_profiles were added on analogy with P2S to fix exactly
this symptom, and the reporter's own debug line proves they do not.
An ssl.SSLError from connect() now opens a five-minute cool-off for that
printer. Subsequent connects return False without touching the network, so a
wedged printer is contacted twice an hour instead of hundreds of times a
minute, and the single warning that is logged names the remedy. The cool-off
is dropped on expiry rather than kept, so the map holds one key per currently
wedged printer. ftps_handshake_blocked() lets the sweeps stop: the 3MF lookup
abandons the remaining paths and skips the directory-walk fallback, the cover
endpoint returns 503 naming the file service instead of a 404 that reads as
"this print has no thumbnail", and the timelapse scan separates 503 (cannot
reach the printer) from 404 (no timelapse directory) -- one 500 used to cover
both, which is what the reporter hit when reproducing.
The Connection Diagnostic completed a bare TCP connect to 990, which is why it
reported the port green throughout: the port is open, it is what is behind it
that is broken. It now completes a real implicit-TLS handshake using the
model's own ftp_profiles cap, so a pass means the FTP client would also get
through. An open port that cannot negotiate reports warn with reason no_tls,
selecting a new message in all 13 locales that points at a printer restart
rather than at the firewall. No login is attempted, so this stays valid in the
pre-save Add Printer flow.
The cool-off tests run against a real socket that accepts on 990 and replies
with a plaintext FTP banner, reproducing WRONG_VERSION_NUMBER rather than
mocking ssl. The autouse fixture clearing _mode_cache now clears the cool-off
map too -- every test here talks to 127.0.0.1, so one left behind would make
the next test's connect() a no-op.
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).
maziggy