List of nested Key-value pairs

Consul
1

Hey! I need some figuring out how process a nested list in Consul’s Key-value store with Consul Template.

My data is stored this way:
kv/service/data/config/process/servers/0/name → string_value
kv/service/data/config/process/servers/0/enabled → boolean_value

kv/service/data/config/process/servers/1/name → string_value
kv/service/data/config/process/servers/1/enabled → boolean_value

I’ve followed Consul-template documentation but for the life of me, I can’t seem to get my head around how to retrieve these nested values.

If possible, I’d like to generate an output like the following:

service:
  data:
    config:
      process:
        servers:
          0:
            name: <server_name>
            enabled: <boolean>
          1:
            name: <server_name>
            enabled: <boolean>

Is this possible to achieve with Consul-template?

2

Hey @jalexander, thanks for asking.

What you want should be possible but how requires a quick initial question… Those entries under servers:, are they fixed so there is always a 0 and 1 (with name/enabled) or is that a variable length list of servers (0…N) that should be generated when the template is run?

3

Thanks for your response. (0…N) as its possible it will be initialized with an empty list if there are no servers.

4

Managed to figure it out… Here’s the approach I took:

servers:
  {{ range $key, $pairs := tree "service/data/config/process/servers/owners" | byKey }}{{ $key }}:
    {{ range $pair := $pairs}}
       {{$pair.Key}}:
         {{$pair.Value}}
  {{ end }}{{ end }}
5

:smile: Exactly the same code that I came up with but you beat me to it.
Glad you figured it out!

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