Why it is occuring KeyError: 'main' and how to solve it - django

Question

I am having keyerror: 'main'. I have searched many sites, but still can't find any satisfactory answer to solve this error. I would really appreciate if someone can give me some pointers. Thanks in advance.
I have tried solving this by adding a function on the init.py which is suggested by a site. But it still didn't work.
https://forum.inductiveautomation.com/t/error-on-sys-modules/6431/2
code: view.py
from django.shortcuts import render
import requests
from .models import City
def index(request):
url = 'http://api.openweathermap.org/data/2.5/weather?q={}&units=imperial&appid=MYKey'
cities = City.objects.all() # return all the cities in the database
city = 'Dhaka'
# request the API data and convert the JSON to Python data types
city_weather = requests.get(url.format(city)).json()
weather_data = []
for city in cities:
# request the API data and convert the JSON to Python data types
city_weather = requests.get(url.format(city)).json()
weather_app = {
'city': city,
'temperature': city_weather['main']['temp'],
'description': city_weather['weather'][0]['description'],
'icon': city_weather['weather'][0]['icon']
}
# add the data for the current city into our list
weather_data.append(weather_app)
#context = {'weather' : weather_app}
context = {'weather_data': weather_data}
# returns the index.html template
return render(request, 'weather_app/index.html')
terminal:
(env) acer#acer-Aspire-V3-472P:~/DjangoProject/Weather$ python manage.py runserver
Watching for file changes with StatReloader
Performing system checks...
System check identified no issues (0 silenced).
May 03, 2019 - 06:48:01
Django version 2.2, using settings 'Weather.settings'
Starting development server at http://127.0.0.1:8000/
Quit the server with CONTROL-C.
Internal Server Error: /
Traceback (most recent call last):
File "/home/acer/DjangoProject/env/lib/python3.6/site-packages/django/core/handlers/exception.py", line 34, in inner
response = get_response(request)
File "/home/acer/DjangoProject/env/lib/python3.6/site-packages/django/core/handlers/base.py", line 115, in _get_response
response = self.process_exception_by_middleware(e, request)
File "/home/acer/DjangoProject/env/lib/python3.6/site-packages/django/core/handlers/base.py", line 113, in _get_response
response = wrapped_callback(request, *callback_args, **callback_kwargs)
File "/home/acer/DjangoProject/Weather/weather_app/views.py", line 30, in index
'temperature': city_weather['main']['temp'],
KeyError: 'main'
[03/May/2019 06:48:18] "GET / HTTP/1.1" 500 68977

Answer 1

You don't check that the data for the specific city is found. You loop through all cities in your database, and try to get the weather for each one; but you don't check that the result is actually returned. You should do:
for city in cities:
response = requests.get(url.format(city))
if response.status_code == 404:
continue
city_weather = response.json()
Also, you should check that you are formatting your URL properly. As it stands, you are inserting your City object directly into the URL - this will only work if you have defined a __str__ method that returns only the city name. It would be better to use the name directly:
response = requests.get(url.format(city.name)) # or whatever the name field is

Answer 2

I'm not sure. I have a suggestion. You may check the city_weatherdata (using print())before making weather_app to see if the key'main'is really in city_weather, maybe the key happened not to be in the data.