commit 5775f07319fa169f83044ee359d275ec1ed6b780
Author: Christopher Teutsch <chris@heychris.eu>
Date:   Wed May 15 20:21:12 2019 +0200

    Initial commit

diff --git a/monitor.py b/monitor.py
new file mode 100644
index 0000000..c336883
--- /dev/null
+++ b/monitor.py
@@ -0,0 +1,152 @@
+#!/usr/bin/env python3
+import requests
+import json
+from typing import List
+from pprint import pprint, pformat
+
+
+class MOT:
+    LONG_DISTANCE_TRAIN = 0
+    REGIONAL_TRAIN = 1
+    COMMUTER_TRAIN = 2
+    UNDERGROUND_TRAIN = 3
+    TRAM = 4
+    BUS = 15
+    ELEVATED_TRAIN = 6
+    ALL_MODES = [LONG_DISTANCE_TRAIN, REGIONAL_TRAIN, COMMUTER_TRAIN, UNDERGROUND_TRAIN, TRAM, BUS, ELEVATED_TRAIN]
+
+
+ALL_LINES = []
+TRIP_CANCELLED = -9999
+
+
+def t(s: str) -> str:
+    """
+    Encode a string to be used as a station identifier.
+    :param s: a string to encode
+    :return: the encoded string
+    """
+    return s.replace(' ', '+')
+
+
+def make_request_data(station_id: int, result_count: int = 8, modes: List = MOT.ALL_MODES, lines: List[str] = ALL_LINES) -> dict:
+    """
+    Prepare a request data dictionary to put into get_data()
+    :param station_id: an EFA station ID
+    :param result_count: how many departures to return
+    :param modes: which modes of transport to use
+    :param lines: which lines to use (line identifiers look like 'provider:line ID: :direction ID',
+    e.g. 'rbg:70070: :H' for the Rheinbahn U70 to Düsseldorf Hbf.
+    :return: a dictionary with the data necessary to make a request to the Abfahrtsmonitor API.
+    """
+    """
+    The request data dictionary can have the following items:
+    
+    stationID: a numerical EFA station ID
+    stationName: (optional) the station's name
+    platformVisibility: (optional) ???
+    transport: a comma-separated list of the modes of transport to be displayed. See the constants for values.
+    useAllLines: display all available lines or filter them using the linesFilter
+    linesFilter: a JSON array with the lines to be displayed. See lines_filter for the format
+    optimizedForStation: (optional) ???
+    rowCount: the amount of results to be returned
+    refreshInterval: (optional) (display parameter) refresh rate in seconds for the browser UI
+    distance: (optional) (display parameter) distance from the monitor to the stop
+    marquee: (optional) (display parameter) make the path text scroll sideways
+    sortBy: (optional) ???
+    """
+    request_data = {
+        'stationId': int(station_id),
+        'rowCount': result_count
+    }
+
+    # sanity check: do the modes exist?
+    for mode in modes:
+        if mode not in MOT.ALL_MODES:
+            raise ValueError(str(mode) + "Unknown transport mode!")
+
+    # Add the list to the data dictionary
+    request_data['transport'] = ','.join("{0}".format(n) for n in modes).rstrip(',')
+
+    if lines is ALL_LINES:
+        request_data['useAllLines'] = 1
+    else:
+        lines_dictarr = [{'data': t(v)} for v in lines]
+        request_data['linesFilter'] = json.dumps(lines_dictarr)
+        request_data['useAllLines'] = 0
+
+    # finally, add the HTML naming
+    request_data = {"table[departure][{0}]".format(k): v for k, v in request_data.items()}
+    return request_data
+
+
+def get_data(request_data: dict, headers: dict = None, cookies: dict = None) -> dict:
+    url = 'https://abfahrtsmonitor.vrr.de/backend/api/stations/table'
+    reply = requests.post(url, data=request_data, headers=headers, cookies=cookies)
+    reply.raise_for_status()
+    print('Request time elapsed: ' + str(reply.elapsed))
+    return reply.json()
+
+
+lines_filter = [
+    'rbg:70070: :H',  # U70 -> Düsseldorf Hbf
+    'rbg:70070: :R',  # U70 -> Krefeld Rheinstr
+    'rbg:70076: :H',  # U76 -> Düsseldorf Hbf
+    'rbg:70076: :R',  # U76 -> Krefeld Rheinstr
+]
+
+
+def is_cancelled(trip: dict) -> bool:
+    if trip['delay'] is not None:
+        return int(trip['delay']) == TRIP_CANCELLED
+    return False
+
+
+def is_late(trip: dict) -> bool:
+    if trip['delay'] is not None:
+        return int(trip['delay']) > 0
+    return False
+
+
+def is_early(trip: dict) -> bool:
+    if trip['delay'] is not None:
+        return int(trip['delay']) < 0 and int(trip['delay']) != TRIP_CANCELLED
+    return False
+
+
+reply_data = get_data(
+    make_request_data(
+        20021002,
+        8,
+        #lines=lines_filter
+    )
+)
+
+# Pretty-print the reply data.
+"""print("Data:")
+pprint(reply_data)"""
+
+
+def fixup_data(d: dict) -> dict:
+    for trip in d['departureData']:
+        if trip['delay'] == '':
+            trip['delay'] = None
+    return d
+
+
+def fmt_trip(trip: dict) -> str:
+    trip_part = "The {}:{} {} (???:{}: :{}) service to {} ".format(trip['hour'], trip['minute'], trip['lineNumber'], trip['lineCode'], trip['directionCode'], trip['direction'])
+    if is_cancelled(trip):
+        status_part = "is cancelled, {}:{} ({}) -> {}:{} ({})".format(trip['orgFullTime'], trip['orgHour'], trip['orgMinute'], trip['fullTime'], trip['hour'], trip['minute'])
+    elif is_late(trip):
+        status_part = "is {} minutes late.".format(trip['delay'])
+    elif is_early(trip):
+        status_part = "is {} minutes early.".format(-trip['delay'])
+    else:
+        status_part = "is on time."
+    return trip_part + status_part
+
+
+reply_data = fixup_data(reply_data)
+for t in reply_data['departureData']:
+    print(fmt_trip(t))