Build a 7-Day Departure Board with Aviationstack

				
					import json, re, sys, time, urllib.error, urllib.parse, urllib.request
from datetime import date, timedelta

API_KEY = "ADD YOUR SECRET"
BASE_URL = "http://api.aviationstack.com/v1"


def call_api(endpoint, **params):
    url = f"{BASE_URL}/{endpoint}?" + urllib.parse.urlencode({"access_key": API_KEY, "limit": 10, **params})
    for wait in (5, 60, None):  # first retry after 5s, then 60s
        time.sleep(2)  # space out calls; to avoid rate-limiting
        try:
            with urllib.request.urlopen(url, timeout=30) as r:
                body = json.load(r)
        except urllib.error.HTTPError as e:  
            body = json.load(e)
        err = body.get("error")
        if not err:
            return body.get("data") or [], None
        if wait and "rate" in json.dumps(err).lower():
            time.sleep(wait)
            continue
        return [], err


up = lambda s: s and s.upper()


def hhmm(t):
    m = re.search(r"[T ](\d\d:\d\d)", t or "")
    return m and m.group(1)


def live(f):
    d, cs = f["departure"], f["flight"].get("codeshared")
    return {"flight": f["flight"]["iata"], "airline": f["airline"]["name"], "to": f["arrival"]["iata"],
            "time": hhmm(d["scheduled"]), "gate": d["gate"], "delay": d["delay"], "status": f["flight_status"],
            "operated_by": cs and up(cs["flight_iata"])}


def future(f):
    cs = f.get("codeshared")
    return {"flight": up(f["flight"]["iataNumber"]), "airline": (f["airline"]["name"] or "").title(),
            "to": up(f["arrival"]["iataCode"]), "time": hhmm(f["departure"]["scheduledTime"]),
            "gate": f["departure"]["gate"] or None, "delay": None, "status": "scheduled",
            "operated_by": cs and up(cs["flight"]["iataNumber"])}


def board(airport):
    today, days, restricted = date.today(), {}, None
    for n in (0, 1, 2, 3, -1, -2, -3):  # today, future, then past (past often not on plan)
        day = (today + timedelta(n)).isoformat()
        if n == 0:
            rows, err = call_api("flights", dep_iata=airport)
            flights = [live(f) for f in rows]
        elif n > 0:
            rows, err = call_api("flightsFuture", iataCode=airport, type="departure", date=day)
            flights = [future(f) for f in rows]
        else:
            rows, err = restricted or call_api("flights", dep_iata=airport, flight_date=day)
            flights = [live(f) for f in rows]
            if err and err.get("code") == "function_access_restricted":
                restricted = ([], err)  # don't waste calls on the remaining past days
        days[day] = {"flights": flights, **({"error": err} if err else {})}
    return {"airport": airport, "days": dict(sorted(days.items()))}


if __name__ == "__main__":
    airport = (sys.argv[1:] or ["JFK"])[0].upper()
    path = f"departures_{airport}_{date.today()}.json"
    with open(path, "w") as f:
        json.dump(board(airport), f, indent=2)
    print(f"Saved {path}")