satnogs-db/db/base/management/commands/fetch_data.py

import requests
from datetime import datetime, timedelta
from pytz import timezone

from django.core.files.base import ContentFile
from django.core.management.base import BaseCommand
from django.conf import settings

from db.base.models import Satellite, Transmitter, DemodData


class Command(BaseCommand):
    help = 'Fetch Satellite data from Network'

    def handle(self, *args, **options):
        apiurl = settings.NETWORK_API_ENDPOINT
        data_url = "{0}data".format(apiurl)
        start_date = datetime.utcnow() - timedelta(days=int(settings.DATA_FETCH_DAYS))
        start_date = datetime.strftime(start_date, '%Y-%m-%dT%H:%M:%SZ')
        params = {'start': start_date}
        response = requests.get(data_url, params=params)

        satellites = Satellite.objects.all()

        for obj in response.json():
            norad_cat_id = obj['norad_cat_id']
            data_id = obj['id']
            station = obj['station_name']
            lat = obj['station_lat']
            lng = obj['station_lng']
            try:
                satellite = satellites.get(norad_cat_id=norad_cat_id)
            except Satellite.DoesNotExist:
                continue
            try:
                transmitter = Transmitter.objects.get(uuid=obj['transmitter'])
            except Transmitter.DoesNotExist:
                transmitter = None

            DemodData.objects.filter(data_id=data_id).delete()

            for demoddata in obj['demoddata']:
                payload_url = demoddata['payload_demod']
                timestamp = datetime.strptime(payload_url.split('/')[-1].split('_')[0],
                                              '%Y%m%dT%H%M%SZ').replace(tzinfo=timezone('UTC'))
                frame = str(requests.get(payload_url).json())
                payload_frame = ContentFile(frame, name='network')

                DemodData.objects.create(satellite=satellite, transmitter=transmitter,
                                         data_id=data_id, payload_frame=payload_frame,
                                         timestamp=timestamp, source='network',
                                         station=station, lat=lat, lng=lng)