Can't use #{ENV['FOO_BAR']} expressions in @jfrog_send_metrics ddtags

[gangefors]

The ddtags array doesn't support rupy expressions in the strings.

In most places you can use #{} to include ruby code but in the ddtags array there is no such support.

config

      <match jfrog.metrics.**>
        @type jfrog_send_metrics
        target_platform "DATADOG"
        apikey "#{ENV['DATADOG_API_KEY']}"
        url "https://api.#{ENV['DATADOG_API_HOST']}/api/v2/series"
        ddtags [
          "env:#{ENV['JPD_ENV']}",
          "hostname:#{ENV['JPD_HOSTNAME']}",
          "version:#{ENV['JPD_VERSION']}"
        ]
      </match>

fluentd logs

Additional tags to be added to metrics are
env:#{ENV['JPD_ENV']}
hostname:#{ENV['JPD_HOSTNAME']}
version:#{ENV['JPD_VERSION']}
Sending received metrics data

In datadog the values become

env:_env_jpd_env
hostname:_env_jpd_hostname
version:_env_jpd_version

DD tags should be able to use dynamic values.

[gangefors]

I worked around this issue by using helm variables but this shouldn't be needed when all other dynamic variables comes from env. vars.

      <match jfrog.metrics.**>
        @type jfrog_send_metrics
        target_platform "DATADOG"
        apikey "#{ENV['DATADOG_API_KEY']}"
        url "https://api.#{ENV['DATADOG_API_HOST']}/api/v2/series"
        ddtags [
          "env:{{ .Values.jfrog.environment }}",
          "hostname:{{ .Values.jfrog.hostname }}",
          "version:{{ .Values.jfrog.version }}"
        ]
      </match>