Understanding and then creating a YAML configuration file

Question

I'm looking into YAML and must admit, I'm struggling a bit. I have a program which reads a JSON config file (and works just fine) but I am refactoring it to work with a YAML config file, for one, my own education and two, a more human friendly config file for users.

In short, I want to have two key value pairs, eg

log-file: /var/log/file

api-key: /api/key

which are only defined once. I then wish to define a host, and be able to have multiple hosts in my configuration file.

Here is an example of a host.

fqdn: firewall.example.com.
project_id: fluffy-penguin-242411
managed_zone: example
domain: example.com
ttl: 60
interval: 600

Is there anyone here who can help me define a YAML file which I can easily work with in Python?

I've managed to get basic configurations into my code, but not a configuration which matches with what I want to do.

Ultimately, I want to be able to have a list or a dictionary of hosts which I can iterate through.

Cheers,

C

Update

I think I might be on the right track with something like this

api-key: './ddns-api-key.json'
log-path: './ddns.log'
hosts:
    -   fqdn: 'firewall.example.com.'
        project_id: 'fluffy-penguin-242411'
        managed_zone: 'example'
        domain: 'example.com'
        ttl: 60
        interval: 600

Answer 1

You can't do exactly that, but you can do something similar by using a named key/value pair object in a list, like so:

api-key: './ddns-api-key.json'
log-path: './ddns.log'
hosts:
    - host1:
        fqdn: 'firewall.example.com.'
        project_id: 'fluffy-penguin-242411'
        managed_zone: 'example'
        domain: 'example.com'
        ttl: 60
        interval: 600
    - host2:
        fqdn: 'stuff.example.org.'
        project_id: 'fluffy-bear-213461'
        managed_zone: 'example'
        domain: 'example.org'
        ttl: 70
        interval: 700

You'll just have to use a unique name for each list entry - I used host1 , host2 , etc. in this example.

Answer 2

I believe that the following which I came up with, and with the help of connectyourcharger from the above post, works:

api-key: './ddns-api-key.yaml'
logfile: './ddns.log'
hosts:
    -   host: 'firewall.example.com.'
        project_id: 'fluffy-penguin-242411'
        managed_zone: 'example'
        domain: 'example.com'
        ttl: 60
        interval: 600

    -   host: 'www.example-two.com.'
        project_id: 'fluffy-penguin-242411'
        managed_zone: 'example-two'
        domain: 'example-two.com'
        ttl: 60
        interval: 600

When I access this using the following python, I am able to loop through the YAML hosts and retrieve all the configuration items.

import yaml

# Read YAML file
with open("configuration.yaml", 'r') as stream:
    try:
        yaml_data = yaml.safe_load(stream)
    except yaml.YAMLError as exc:
        print(exc)

print(yaml_data['api-key']) # prints ./ddns-api-key.yaml

for host in yaml_data['hosts']:
    print(host['host'])    # prints firewall.example.com and www.exmaple-two.com
    print(host['ttl'])     # prints 60 twice
    print(host['domain'])  # prints example.com and example-two.com

Cheers, C