DDOI Translator Modules

A large part of DDOI is a decoupling of observation planning from instrument specific code. However, in order to actually run an observation plan at the observatory, an interface layer needs to exist to translate instrument agnostic plans into low level (KTL, epics, music, etc) commands on hardware. This module provides the base code needed to implement that interface layer for any subsystem.

Installation

Eventually, this package will be provided directly through kroot. However, until that deployment happens, this package needs to be installed manually.

1. Clone this repo:

   git clone https://github.com/KeckObservatory/DDOITranslatorModule.git

2. Install the package:

   cd DDOITranslatorModule
   pip install .

3. Check that the installation was successful:

   python
   >>> import ddoitranslatormodule

   If no exceptions are raised, the installation was succesful.

Quickstart

What follows is a short example of how to create a single translator module function. For more information on what specifically should be in a single function, see the Module Design section (coming soon).

First, import the required pieces from this package

# The base function itself:
from ddoitranslatormodule.BaseFunction import TranslatorModuleFunction
# Custom DDOI exceptions:
from ddoitranslatormodule.DDOIExceptions import *

Next, create a class that extends the TranslatorModuleFunction, and create the __init__ method:

class MODULE_NAME_HERE(TranslatorModuleFunction):

    def __init__(self):
        super().__init__()

Finally, add the pre_condition, perform, and post_condition methods:

class MODULE_NAME_HERE(TranslatorModuleFunction):

    def __init__(self):
        super().__init__()

    @classmethod
    def pre_condition(cls, args, logger, cfg):
        print("Pre condition")
        return True

    @classmethod
    def perform(cls, args, logger, cfg):
        print("Perform")
        return True

    @classmethod
    def post_condition(cls, args, logger, cfg):
        print("Post condition")
        return True

Replace the contents of these methods with whatever code makes sense for your use case. Generally, pre_condition should only contain code that verifies that perform should execute, and post_condition should contain code that verifies that the expected change took place. For example, if this module function were implementing a filter changing operation, the pre_condition might check if the system is online, the perform method could command the filter wheel to rotate, and the post condition could verify that the correct filter is in place. It does not always makes sense for there to be a pre and post condition, if that is the case, then simply return True.

Module Structure

The instructions above only describe how to make a single translator function, not the whole collection of commands needed to control an entire subsystem. This section will summarize how the whole module should be structured, what files are required, and how the module should be used.

MODULE_NAME

├── module_name

│ ├── __init__.py

│ └── subsection1

│ │ └── __init__.py

│ │ └── sub1functionA.py

│ │ └── sub1functionB.py

│ │ └── sub1functionC.py

│ └── subsection2

│ │ └── __init__.py

│ │ └── sub2functionA.py

│ │ └── sub2functionB.py

│ │ └── sub2functionC.py

├── LICENCE.txt

├── .gitignore

├── requirements.txt

├── setup.py

├── __init__.py