Origins Generators

An Origins generator extracts or derives facts from an existing service or file. Generators will invoked using the origins generate <name> subcommand.

To make calling a generator consistent, a few simply conventions must be followed:

• All generators must write data to standard out
• All generators must emit facts in the CSV format and include the header
• All generators should use standard POSIX flags (see http://docopt.org for a solid starting point)

For convention, each generator in this respository will be maintained in a generators/<name> with the same name it will be invoked with.

Since generators can implemented using any technology, a Dockerfile should be included that encapsulates the program to make it simpler to call without needing to install any dependencies.

Example

This is a trivial, but valid example of what a program could look like.

#!/usr/bin/env python

import os
import sys
import csv
import time

# Minimum possible header.
HEADER = (
    'entity',
    'attribute',
    'value',
)

def main(root):
    "Outputs last modified times of the files in the specified directory."
    # Creating a CSV writer that feeds to stdout.
    w = csv.writer(sys.stdout)

    # Write the header to start.
    w.writerow(HEADER)

    for path in os.listdir(root):
        w.writerow((
            path,
            'last_modified',
            time.ctime(os.path.getmtime(path)),
        ))

    # Flush the remaining bits.
    sys.stdout.flush()

if __name__ == '__main__':
    main(*sys.argv[1:])