octoturgeandClaude Opus 5
6ff0c9a649
Two changes, both following from the print that paused at 1% because
`use_ams: false` pointed an AMS-sliced project at the external spool.
## upload_project_file no longer guesses
It now reads the `.3mf` it already holds and works out where each filament
should come from. `Metadata/slice_info.config` names every filament's
`tray_info_idx`, type and colour; the AMS report names the same three per
loaded tray; matching them is the whole job. `src/printer/project_file.rs`
does the reading and matching and is free of printer types, so it is
testable without a printer - which is the only way this gets tested at all,
the alternative being to notice a mapping bug by watching a machine print in
the wrong colour.
The mapping is derived *before* the upload: a project that cannot be matched
should not result in a file being moved onto the machine that cannot then be
printed.
It never falls back to the external spool to make an unmatched project
"work". The one case it answers `ExternalSpool` for is a printer reporting no
AMS trays at all. A printer *with* an AMS whose project wants the spool is an
error, not a fallback, because `vt_tray` is not modelled on `PrintReport` -
there is no way to check the spool holds the right material, and claiming a
match without checking is how this went wrong the first time.
Two fixtures carry the real cases: `cube_slice_info.3mf` is the project that
cost the print (deflated on purpose - every other test archive is Stored, so
the decompression path and the flate2 backend behind zip's `deflate-flate2`
would otherwise never run), and the existing `push_status_v1_p1p_idle.json`
supplies the AMS side. The end-to-end test asserts they agree on
`[3,-1,-1,-1,-1]`: both slots hold PETG GFG99 and only the colour tells them
apart, so a matcher stopping at `tray_info_idx` would print the cube in
black.
A malformed `<filament>` element is an error rather than a skip. A skipped
filament leaves a hole at its index, the hole becomes `-1`, and the printer
is told that material is unused - so the plate prints in whatever remains
mapped.
New dependency: `zip` 9.0.3 (MIT) with `deflate-flate2`, plus `flate2` for a
backend, which zip's feature does not select on its own. All six new crates
are MIT, MIT/Apache-2.0, 0BSD/MIT/Apache-2.0, MIT/Zlib/Apache-2.0 or Zlib,
and `cargo deny check licenses` passes. No bzip2, lzma, xz or zstd entered
the graph.
## Lights on completion
`completion::run` is a third daemon task that notices a print finishing and
blinks that printer's chamber light for ten seconds, then leaves it off:
500ms on, 500ms off, twenty commands, ending dark.
Its own task rather than a branch in the uplink's telemetry loop, because
that loop only ticks while the cloud connection is up - and a light that only
works when the internet does is not much of a notification for someone
standing next to the printer.
Three rules, each a false celebration avoided and each tested: only a
*transition* into `FINISH` fires, because `FINISH` persists until the next
print starts; a printer seen for the first time never fires, so restarting
the gateway does not announce prints that finished yesterday; and `FAILED`
never fires, because that is what a Bambu reports for a cancellation,
including every `print.stop` this software sends.
The blink is driven from `On`/`Off` rather than the firmware's `flashing`
mode. `flashing` is in the schema but the meaning of `loop_times` versus
`interval_time` is unconfirmed, so "blink for ten seconds" could not be
predicted; two obvious commands give an exact duration. The light is left off
even when a blink fails part-way, since a machine abandoned with its light on
looks like one still working.
`set_light` is **unverified against hardware** - the P1P was powered off when
this was written, and the doc comment says so. The shape is built from
`schemas/bambulab/{v1,v2}/request/system/ledctrl.schema.json` rather than by
hand, and it goes out as a correlated request so a rejection is visible.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
continuum-proxy
Edge gateway daemon for the Continuum print farm platform. Runs on a Linux
SBC on-site, talks to printers over the LAN, and keeps a connection to the
cloud control plane (continuum-backend).
What's real right now
- Bambu MQTT - a real client for both protocol generations (MQTT
v3.1.1+BambuMQTT v1 on older firmware, MQTT v5+BambuMQTT v2 on current
firmware), auto-detected per printer on connect (a firmware update can
move the same physical printer between them, so this isn't something
config can hard-code once and forget - see
printer/bambu.rs'sBambuProtocolPreference::Auto). Request/reply correlation viasequence_id, an in-memoryprint.push_statuscache that merges v1's partial updates and replaces on v2's full ones, and TLS trust that auto-pins a printer's certificate via trust-on-first-connect the first time the bundled CA doesn't verify (printer/bambu.rs'sensure_trusted) - seeprinter/bambu_mqtt.rs's doc comment for the full protocol write-up. - Marlin/RepRap serial - a real held-open serial connection that paces
gcode lines by Marlin's own "ok" acknowledgment (
printer/marlin_serial.rs). - Wire shapes from schemas, not hand duplication - Bambu's raw MQTT
JSON is built straight from
continuum-schemas' JSON Schema files viacontinuum-schema-instance, instead of a second hand-written copy of every request shape drifting out of sync with the schema. - Cloud uplink - a WebSocket client to
continuum-backendthat connects, sends a heartbeat on a timer, and reconnects on drop (src/uplink/). - go2rtc watchdog - restarts the camera-restreaming subprocess if it
dies (
src/go2rtc.rs). - Bambu file upload - implicit FTPS (port 990) into the printer's own
cache/directory (src/printer/bambu_ftps.rs, viaBambuPrinter::upload_file). Confirmed live against a P1P on 2026-10-03: login, binary mode, and the transfer all work, byte count matched exactly. - Print status -
print.push_statusparsed intoPrintReportwith real job progress, temperatures, fans and HMS entries. Confirmed live on both generations (idle P1P on v1, H2C 20% into a job on v2); regression fixtures from those captures are intests/fixtures/.
Examples worth knowing
cargo run --example live_reports [printer-id]- read-only, safe against a printer that is mid-print. Connects, reports firmware, and watches the status stream. Redirect stderr to capture raw payloads.cargo run --example bambu_idle_checks -- <printer-id>- writes (FTPS upload, fan speed). Requires an explicit printer id and refuses to run unless that printer reportsgcode_state: "IDLE".
What routes between the cloud and the printers
The uplink and the printer fleet are wired together, in both directions
(uplink/mod.rs):
- Up: every 5s, one
PrinterTelemetrysnapshot per printer that has reported, batched into a singleTelemetrymessage. Verified live against a P1P and an H2C. - Down: a
Commandfrom the cloud is looked up by our own printer id, executed, and answered with aCommandResult. The set of commands is deliberately small - a fan speed and a single gcode line - and deliberately has no "start a print" variant; seePrinterCommand.
One quirk worth knowing: a Bambu on protocol v1 only sends a complete
status when asked, so each telemetry tick also fires a pushing.pushall for
the next one. A v1 printer's telemetry is therefore one tick behind, which
is why it shows up on the second frame rather than the first.
What's still a stub
start_uploaded_file - the MQTT command that actually starts a print from
an uploaded file - is written but has deliberately never been fired, since
that commits a machine to hours of work. Its doc comment lists the three
details to confirm on the first real attempt. upload_file is proven, but
only with a small text file, not a multi-megabyte sliced .3mf.
PrusaLink (REST) and Klipper/Moonraker (WebSocket) - printer/prusa.rs
and printer/klipper.rs just println! what they'd send. Also not built
yet: local buffering for telemetry across connectivity gaps (so telemetry
produced while the uplink is down is simply lost), LAN printer discovery
(SSDP/mDNS), and the mechanical plate-changer interface.
Getting started
cp .env.example .env
cargo run # the daemon: connects every configured printer, then runs the cloud uplink + go2rtc watchdog
cp printers.example.toml printers.toml # fill in your real printers (gitignored)
cargo run --example auto_connect_bambu # checks/auto-pins each Bambu printer's certificate, no MQTT needed
cargo run --example test_bambu_certs # narrower: just the raw TLS handshake, no auto-pinning
cargo run --example printer_polymorphism # standalone trait+enum demo, fake data, no network/env needed
cargo run --example bambu_commands_demo # round-trips hand-written structs against real captured Bambu JSON
Structure
src/
main.rs Loads+connects the printer fleet, then runs the uplink and go2rtc watchdog side by side
config.rs Loads settings from environment variables
fleet.rs Loads printers.toml into ready-to-use PrinterHandles
uplink/ WebSocket client to continuum-backend: connect, heartbeat, reconnect on drop
go2rtc.rs Restarts the go2rtc camera-restreaming process if it dies
printer/
mod.rs GenericPrinter trait + PrinterBase + PrinterHandle enum - the trait+enum
"inheritance" pattern this project uses instead of class inheritance
bambu.rs The real Bambu printer type: cert trust, protocol version auto-detect, commands
bambu_mqtt.rs The real MQTT wiring underneath bambu.rs - see its doc comment for the protocol details
bambu_commands/ Hand-written serde structs mirroring continuum-schemas' bambulab/ shapes
marlin_serial.rs A real held-open Marlin/RepRap serial connection
prusa.rs, klipper.rs Still stubs - see "What's still a stub" above
examples/
auto_connect_bambu.rs Checks/auto-pins every Bambu printer's certificate (no MQTT)
test_bambu_certs.rs Narrower: just a raw TLS handshake per Bambu printer
printer_polymorphism.rs Standalone trait+enum demo, five fake printers, no network needed
bambu_commands_demo.rs Round-trips bambu_commands' structs against real captured Bambu JSON
printers.toml (gitignored - copy from printers.example.toml) holds real
per-printer connection details: host, access code/API key/serial port
depending on vendor, and - for Bambu - an optional per-printer CA
certificate override (see certs/README.md; most printers don't need one,
since connect() auto-pins automatically).
Learning Rust through this repo
src/printer/mod.rs's doc comment is where the "how do I do inheritance
without classes" question lives - trait (shared behavior) + struct
(shared fields) + enum (the closed set of concrete types), instead of
GenericPrinter -> BambuPrinter/PrusaLinkPrinter/... class inheritance.
Run printer_polymorphism to see it work end to end without needing any
real printer on the network.