launch_discovery.py

#!/usr/bin/env python
"""This module will launch Discovery on http://localhost:1234

This file will automatically scan for a folder of discovery binaries.
If the binaries are not detected, the script will launch the Discovery docker container.

Available functions:
- launch_discovery: Starts discovery container or binaries
"""
import fnmatch
from multiprocessing import Process
import os
import subprocess
import sys

from discovery_config import DISCOVERY_CONFIG, DISCOVERY_PORT, DISCOVERY_IMAGE_NAME


def launch_discovery(custom_directory=None, type=None, port=None, discovery_config=None):
    """Launches the Discovery engine either via docker container or via compiled binaries.

    Args:
        custom_directory: File path to the custom directory would like uploaded to discovery.
        type: String, can either be 'docker' or 'binaries'
    """
    if custom_directory is None:
        custom_directory = os.getcwd()
    if port is None:
        port = DISCOVERY_PORT
    if discovery_config is None:
        discovery_config = DISCOVERY_CONFIG
    if type is None:
        type = _determine_discovery_launch_type()

    if type == 'docker':
        return _launch_container(custom_directory, port, discovery_config)

    return _launch_binaries(custom_directory, port, discovery_config)


def _determine_discovery_launch_type():
    binaries_directory = _detect_binaries_file()
    if binaries_directory:
        return 'binaries'
    return 'docker'


def _launch_container(custom_directory, port, discovery_config):
    """launches the Discovery docker container."""
    dico_dir = ["-v", "{}/dico:/dico".format(custom_directory)] if os.path.isdir(custom_directory + '/dico') else []

    try:
        config_items = discovery_config.iteritems()
    except AttributeError:
        config_items = iter(discovery_config.items())

    # yapf: disable
    launch_command = ' '.join(
        ["docker", "run", "--rm", "-d"] +
        ["--name", "discovery-dev"] +
        ["-v", '"{}":/custom'.format(custom_directory)] +
        ["-p", "{}:1234".format(port)] +
        dico_dir +
        ["-e {}={}".format(k, v) for k, v in config_items] +
        [DISCOVERY_IMAGE_NAME]
    )
    # yapf: enable
    print("Launching Discovery from Container: {}\n".format(launch_command))

    subprocess.call(launch_command, shell=True)


def _launch_binaries(custom_directory, port, discovery_config):
    """launches Discovery from the compiled binaries."""
    binaries_directory = _detect_binaries_file()
    if binaries_directory:
        sys.path.append(os.path.abspath(binaries_directory))
        from run import find_definition_files_and_copy_them_to_appropriate_location
        find_definition_files_and_copy_them_to_appropriate_location(
            os.path.join(custom_directory), os.path.abspath(binaries_directory)
        )

        sys.path.append(os.path.join(binaries_directory, 'discovery'))

        print("Launching Discovery from Binaries: {}\n".format(binaries_directory))

        os.environ["SERVICE_NAME"] = "discovery"
        from discovery.server import main

        proc = Process(target=main, args=())
        proc.start()


def _detect_binaries_file():
    """Returns the absolute path of the binaries directory."""
    for file in os.listdir('.'):
        if fnmatch.fnmatch(file, 'discovery_binaries_*') and not file.endswith('.tar.gz') and not file.endswith('.zip'):
            return os.path.abspath(file)
    return None


if __name__ == '__main__':
    directions_custom_directory = os.path.join(os.getcwd(), 'examples', 'directions', 'custom')
    launch_discovery(custom_directory=directions_custom_directory)