README.md

YAML-Defined Action Initialization

Actions can be manually initialized in actions/__init__.py, but an easier method for non-developers and configuration-management software is to place a YAML file in this directory which contains the action class name and parameter definitions.

The file name can be anything. Files must end in .yml.

The action initialization logic parses all YAML files in this directory and registers the requested actions in the API.

Let's look at an example.

Example

Let's say we want to make an instance of the SingleFrequencyFftAcquisition.

First, create a new YAML file in this directory. In this example we're going to create an acquisition for the LTE 700c band downlink, so we'll call it acquire_700c_dl.yml.

Next, we want to find the appropriate string key for the SingleFrequencyFftAcquisition class. Look in actions/__init__.py at the action_classes dictionary. There, we see:

action_classes = {
    ...
    "single_frequency_fft": acquire_single_freq_fft.SingleFrequencyFftAcquisition,
    ...
}

That key tells the action loader which class to create an instance of. Put it as the first non-comment line, followed by a colon:

# File: acquire_700c_dl.yml

single_frequency_fft:

The next step is to see what parameters that class takes and specify the values. Open up actions/acquire_single_freq_fft.py and look at the documentation for the class to see what parameters are available and what units to use, etc.

class SingleFrequencyFftAcquisition(Action):
    """Perform m4s detection over requested number of single-frequency FFTs.

    :param name: the name of the action
    :param frequency: center frequency in Hz
    :param gain: requested gain in dB
    :param sample_rate: requested sample_rate in Hz
    :param fft_size: number of points in FFT (some 2^n)
    :param nffts: number of consecutive FFTs to pass to detector

    """
    ...

Lastly, simply modify the YAML file to define any required parameters.

# File: acquire_700c_dl.yml

single_frequency_fft:
  name: acquire_700c_dl
  frequency: 751e6
  gain: 40
  sample_rate: 15.36e6
  fft_size: 1024
  nffts: 300

You're done. You can define multiple actions in a single file.