Question

I have a list of consumers:

API_CONSUMERS = [{'name': 'localhost',
                  'host': '127.0.0.1:5000',
                  'api_key': 'Ahth2ea5Ohngoop5'},
                 {'name': 'localhost2',
                  'host': '127.0.0.1:5001',
                  'api_key': 'Ahth2ea5Ohngoop6'}]

And I have a host variable:

host = '127.0.0.1:5000'

I want to:

1. Check if host is in the values in the list of API_CONSUMERS, then
2. If the host exists retrieve the api_key to use elsewhere.

Originally I was checking the host values like this:

if not any(consumer['host'] == host for consumer in API_CONSUMERS):
    #do something

But then realised to retrieve the api_key I would have to loop through each consumer anyway, so might as well combine the two:

for consumer_info in API_CONSUMERS:
    if consumer_info['host'] == host:
        consumer = consumer_info
if not consumer:
    #do something

What is the best way to do this? I feel like what I’m doing isn’t “pythonic”.

Solution

try:
    api_key = next(d['api_key'] for d in consumers if d['host'] == host)
except StopIteration:
    #do something

Answer 1

>>> next(consumer['api_key'] for consumer in API_CONSUMERS if consumer['host'] == host)
'Ahth2ea5Ohngoop5'

Don’t forget to catch the exception that will be raised if the value is not found.