worker.py

import argparse
import json
import logging
import os

from h.events import AnnotationEvent
from h.models import Annotation

from pyramid import paster
from pyramid.request import Request

log = logging.getLogger('h.worker')

parser = argparse.ArgumentParser('eventworker')
parser.add_argument('config_uri')


def main():
    args = parser.parse_args()
    paster.setup_logging(args.config_uri)

    base_url = os.environ.get('BASE_URL')
    if base_url is None:
        base_url = 'http://localhost'
        log.warn('BASE_URL not found in environment, using default: %s',
                 base_url)

    request = Request.blank('/', base_url=base_url)
    env = paster.bootstrap(args.config_uri, request=request)
    request.root = env['root']

    loop(request)


def loop(request):
    def handle_message(reader, message=None):
        if message is None:
            return
        data = json.loads(message.body)
        action = data['action']
        annotation = Annotation(**data['annotation'])
        event = AnnotationEvent(request, annotation, action)
        request.registry.notify(event)

    reader = request.get_queue_reader('annotations', 'event-worker')
    reader.on_message.connect(handle_message)
    reader.start(block=True)


if __name__ == '__main__':
    main()