Renamed to dmscid/lewis. Please use that image.
Plankton is a Python framework for simulating hardware devices. It is compatible with both Python 2 and 3.
Plankton can be run directly using Python 2.7 or >= 3.4, or using a prepackaged Docker image that includes all dependencies. See relevant usage sections for details.
Purpose and Use Cases
Plankton is being developed in the context of instrument control at the ESS, but it is general enough to be used in many other contexts that require detailed, stateful software simulations of hardware devices.
We consider a detailed device simulation to be one that can communicate using the same protocol as the real device, and that can very closely approximate real device behaviour in terms of what is seen through this protocol. This includes gradual processes, side-effects and error conditions.
The purpose of Plankton is to provide a common framework to facilitate the development of such simulators. The framework provides a common set of tools and abstracts away protocol adapters, which helps minimize code replication and allows the developer of a simulated device to focus on capturing device behaviour.
Potential use cases for detailed device simulators include:
- Replacing the physical device when developing and testing software that interfaces with the device
- Testing failure conditions without risking damage to the physical device
- Automated system and unit tests of software that communicates with the device
- Perform "dry runs" against test scripts that are to be run on the real device
Using a simulation for the above has the added benefit that, unlike most real devices, a simulation may be sped up / fast-forwarded past any lengthy delays or processes that occur in the device.
Interfaces are two independent concepts in Plankton. The
Device is model for the device behaviour and internal memory. A
Device can be represented using a
StateMachine, but it does not have to be. A
Device does not include anything specific to the communication protocol with the
Interface provides a protocol binding to a
Interface are created as part of a
Simulation that provides a "heart beat" and other environmental aspects.
What Does Plankton Let You Do?
- Create new
Devices to closely imitate the internal behaviour and memory of something
- Optionally make a
Devicework as a
StateMachineDeviceto to give rich behaviours
- Create one or more
Interfaces over your
Deviceto expose it as an EPICS IOC, a TCP listener, or on any other bespoke protocol you like
- Access and control the
Devicewhile it is running via a "back door"
- Access and control the
Simulationwhile it is running via a "back door"
Details on running Plankton, working with Plankton as a device developer, and framework internals are described in the following documents:
- Installation and Usage
- Runtime Control
- Creating Device Simulators
- Contribution Guidelines: New device simulators can be added to Plankton.
- Framework Internals
- Detailed Overview of Framework: Description of framework internals and design decisions.