kilonova 1.0.0

Pure-Python OPC UA servers from quasar Design files — the quasarnova family's no-codegen engine

kilonova

What is this?

kilonova serves a quasar Design.xml + config.xml as a live OPC UA server in pure Python — no code generation, no C++. It produces the same address space as a quasar-generated server (same ns=2 string NodeIds, same dotted parent.child addressing), so quasar ecosystem tools — Cacophony/WinCC OA, UaoForQuasar clients, plain OPC UA clients — work against it unmodified.

A kilonova is the luminous flash of a neutron-star merger — a lighter, faster transient in the nova family. This kilonova is the pure-Python engine of the quasarnova family: successor of MilkyWay (Piotr Nikiel's 2021 pure-Python prototype; this rewrite was briefly named microquasar), rebuilt from scratch on asyncua 2.x.

Basic usage mode

1. Install (Python ≥ 3.10): pip install kilonova
2. Run your existing quasar server's design, unchanged: kilonova run --design Design/Design.xml --config bin/config.xml
3. Point any OPC UA client at opc.tcp://host:4841 — the address space is quasar's.
4. Dump a running server's address space (uasak_dump-style NodeSet2): kilonova dump --endpoint opc.tcp://127.0.0.1:4841 --output dump.xml

Device logic is plain Python (see doc/DeviceLogic.md):

from kilonova import Server

server = Server("Design.xml", config_path="config.xml")

@server.read("sca1.adc")                 # source variable: runs inside the client read
async def read_adc(obj):
    return await hardware.read_adc()

@server.method("sca1.reset")             # method handler
async def reset(obj):
    await obj.setOnline(0)               # generated setter, quasar naming

async with server:
    ...

What works

All 12 cases of quasar's own CI test suite pass against the reference nodesets (cache/source/calculated variables, methods incl. arguments, config entries and restrictions, singleVariableNode, design/config instantiation, StandardMetaData). Production designs were probed against live C++ servers of both backends: ATCA and CAEN at full structural parity; CanOpen surfaced two genuine C++ cross-backend quirks (kilonova sides with one backend on each). Details: doc/Parity.md.

Limitations

• Device logic is registered per address at runtime — there is no generated D<Class> skeleton (that is the point).
• Design-mandated children are instantiated unconditionally; C++ device logic may create some conditionally.
• No server-side security policies yet (NoSecurity endpoint only).
• Values live in asyncua's address space; extreme write rates were not a design goal.

Documentation

• doc/Architecture.md — modules and data flow
• doc/DeviceLogic.md — the user API
• doc/CalculatedVariables.md — formulas, exactly the C++ dialect
• doc/Parity.md — the parity contract and current status
• PLAN.md — milestone log, parity backlog, engineering notes
• CHANGELOG.md — release history
• quasar framework documentation: https://quasar.docs.cern.ch

Credits

• Paris Moschovakos ([e-mail]) — kilonova
• Piotr Nikiel — quasar concept and architecture; MilkyWay, the predecessor

Interface stability

From 1.0.0, kilonova follows semantic versioning. The public API is kilonova.Server (constructor arguments, objects, the method/read/write decorators), kilonova.Design, QuasarObject (set_cv/get_cv/generated setters) and the exceptions in kilonova.errors. Anything imported from other modules is internal. Breaking changes get a deprecation release first.

Contact: [e-mail]

License: BSD-2-Clause.