channel-poll.py

import os
import time

import requests

# export ADN_PROD_TOKEN="<your access token>"
token = os.environ['ADN_PROD_TOKEN']

s = requests.Session()
s.headers['Authorization'] = 'BEARER ' + token


def get_channels(params):
    "Make an API call which fetches the channel inbox."

    # Using the more complex requests API here for illustrative purposes, but
    # return s.get('https://alpha-api.app.net/stream/0/channels', params=kwargs).json()
    # would work just as well

    r = s.get('https://alpha-api.app.net/stream/0/channels', params=params)

    resp = r.json()

    print 'Fetched:', r.url, '->', resp['meta']

    return resp['meta'], resp['data']


def recursive_poll(channel_callback, since_id=None):
    "Recursively fetch channels from the API."

    meta = {}
    first_max_id = None

    while True:
        # Reducing to fetching 2 at a time for dramatic effect,
        # but in production code, you probably want to fetch 200
        # at a time.
        params = {
            'before_id': meta.get('min_id'),  # omitted in first iteration
            'since_id': since_id,
            'count': '2'
        }

        meta, data = get_channels(params)

        channel_callback(data)

        # Only capture this on the first API call
        first_max_id = first_max_id or meta.get('max_id')

        if not meta['more']:
            break

    # Hang on to whatever max ID we got back
    # in the first API call -- we'll use that to
    # poll forward later
    return first_max_id


def process_channels(channels):
    # Do whatever it is that you do with channels.
    for channel in channels:
        print 'Learned about channel', channel['id']


if __name__ == '__main__':
    # First, fetch everything we know about right now.
    print 'Backfilling...'
    max_id = recursive_poll(process_channels)

    # Then poll on a forward basis to get anything new we care about.
    # Because we sort inbox based on most recent message ID, channels
    # with activity will bubble to the top, and you can update them
    # accordingly.
    print 'Polling...'
    while True:
        # If we didn't get any results, ensure that we don't start over every time.
        # (i.e., don't replace max_id with None unless it was None already)
        max_id = recursive_poll(process_channels, since_id=max_id) or max_id
        time.sleep(1)