Add Retire Nexusp Backend for K1C 2025

README.md

@@ -5,3 +5,88 @@
 This script intended for use on Creality **K1 Series** and **Ender-3 V3 Series** printers allows to add more features.
 
 Additional support for K1 2025 by @C0DEbrained.
+
+## Retire Nexusp Backend (K1C 2025)
+
+The K1C 2025 runs **two Moonrakers against one Klipper**: Creality's forked
+`nexusp` on `:7125` (the touchscreen's backend) and this script's real Moonraker
+on `:7126`. They share `-d /usr/data/printer_data`, so one gcode directory and
+one klippy socket, but Creality namespaced the databases.
+
+That split is not merely redundant. Querying the wrong port does not fail — **it
+answers**:
+
+```sh
+curl -s http://<printer>:7125/server/spoolman/status
+# nexusp -> {"error": {"code": 404, "message": "Method not found"}}
+```
+
+Read at face value that says Spoolman was never connected on this printer. It is
+wrong, and every command pasted from a Klipper forum at `:7125` hits it.
+
+**Customize menu → Retire Nexusp Backend** turns nexusp off and moves the real
+Moonraker to `:7125`, the port the rest of the Klipper ecosystem assumes. It is
+opt-in and off by default. The touchscreen is never patched — `vectorp`
+hardcodes `http://127.0.0.1:7125`, and what answers there becomes ours.
+
+The option:
+
+- merges the two print histories before anything is disabled, so the screen does
+  not lose everything printed before this script was installed;
+- installs a small Moonraker component implementing the two JSON-RPC methods the
+  screen calls and stock Moonraker does not have
+  (`server.files.get_directory_ex` and `server.history.count`);
+- offers to install Pillow into Moonraker's virtualenv. Pillow is **not** in the
+  Moonraker this script ships, and Moonraker's own thumbnail parser needs it —
+  without it a freshly uploaded file has no thumbnail on the screen at all;
+- renames the nexusp init script rather than deleting anything.
+
+**Restore Nexusp Backend** undoes all of it, and merges the prints made while
+nexusp was retired back into its database first — otherwise the touchscreen's
+history would silently stop at the day you retired it.
+
+### Caveats
+
+- **A firmware update can put the nexusp service file back.** `/usr/apps/etc/init.d`
+  survives a factory reset, but an OTA can recreate `CS56nexusp_service` beside
+  the disabled copy. It then loses the race for `:7125` to Moonraker and dies
+  silently at every boot. The Information menu reports this with `~`, and
+  running Retire Nexusp Backend again repairs it.
+- **For about four seconds after a cold boot** the screen polls two methods
+  (`printer.info`, `printer.objects.list`) that Moonraker only registers once
+  Klipper connects. It resolves itself and needs no action.
+- Two of the four Creality-only RPC methods are deliberately not implemented:
+  `server.history.debug.job` and `server.debug.status`. Neither is
+  screen-facing.
+- **The two shimmed methods answer over the websocket only.** `curl
+  http://<printer>:7125/server/files/get_directory_ex` returns 404 by design —
+  that is what nexusp did, and matching it is the point. Note that this 404 is
+  identical to the one you get when the component is not loaded at all, so it
+  is not a way to check. To confirm the shim is live:
+
+  ```sh
+  curl -s http://<printer>:7125/server/info
+  ```
+
+  and look for `creality_compat` in `components` (and *not* in
+  `failed_components`).
+
+### Running the tests
+
+Everything ships with tests beside it. They are the executable record of what
+was measured against `nexusp` before it was switched off — once it is retired
+those measurements cannot be re-derived without reviving it. No printer, no
+Moonraker, no network:
+
+```sh
+python3 -m pytest -q
+```
+
+That runs both suites: the Moonraker component and history merge under
+`files/moonraker/creality-compat/`, and the shell option under `tests/`. The
+component suite also runs standalone from its own directory with no conftest.
+
+The shell tests exercise `sed -i` the way the printer does, which is GNU/busybox
+syntax; on macOS they skip unless `gsed` is installed (`brew install gnu-sed`).
+
+This repository has no CI, so nothing runs any of this automatically.