HDM should be able to read global hiera data

[tuxmea]

Discussed in #299

^{Originally posted by tuxmea February 15, 2024}
In some environments, the global hiera data is used (/etc/puppetlabs/puppet/hiera.yaml)
HDM should be able to also show global data.

Workflow in HDM:

• select environment
• select node

1. Global data:

HDM now reads the global hiera.yaml file, replaces the facts and finds the yaml files for the node and collects all Hiera keys.
The global hiera.yaml file may be absent. It should only be taken into account if it has a hierarchy key.

2. Environment data:

HDM reads the environment hiera.yaml file, replaces the facts and finds the yaml files for the node and collects all Hiera keys.

3. Select a key

When selecting a Hiera key, HDM should show the global directory/file structure similar to environment data on top of the environment data.
Global data and environment data views are each have a border around to visualize that these are different data sources.

4. Show result

Show result must first parse global data and environment data afterwards.
lookup_options are dealt in the same way as single environment data.

[oneiros]

I am knee deep into implementing this. It took quite a while but I am finally getting somewhere.

Here is a sneak peek:

I have a question about the location of the global layer's hiera.yml file, though:

According to the hiera docs the location of the global hiera.yaml is $confdir/hiera.yaml by default and can be overridden in puppet.conf (as, I suspect, can $confdir). So it is not always in a fixed location.

Since I assume we do not want to start parsing puppet.conf, how about we add a configuration option to hdm.yml to set the location? This would also be very helpful for testing purposes.

[tuxmea]

looks good. And yes: please make the location of the global hiera.yaml file configurable.

[tuxmea]

One minor request: Instead of Layer: global and Layer: environment:

please use Scope: global and Scope: environment.

Otherwise people might get confused with hiera hierarchy layers.

[oneiros]

One minor request: Instead of Layer: global and Layer: environment:

please use Scope: global and Scope: environment.

I would be happy to use better terminology. But just to make sure: Do you really think is correct? The documentation very consistently refers to the different levels as "layers". They are introduced here:

https://www.puppet.com/docs/puppet/8/hiera_intro.html#hiera_config_layers

And they are referred to several times, e.g. here: https://www.puppet.com/docs/puppet/8/hiera_automatic#puppet_lookup, always as "layers".

Also, when I use the search feature on the documentation page, the top results for "layers" all refer to the these levels of configuration while a search for "scope" returns only results not related to this concept at all 🤷‍♂️

[tuxmea]

One minor request: Instead of Layer: global and Layer: environment:
please use Scope: global and Scope: environment.

I would be happy to use better terminology. But just to make sure: Do you really think is correct? The documentation very consistently refers to the different levels as "layers". They are introduced here:

https://www.puppet.com/docs/puppet/8/hiera_intro.html#hiera_config_layers

And they are referred to several times, e.g. here: https://www.puppet.com/docs/puppet/8/hiera_automatic#puppet_lookup, always as "layers".

Also, when I use the search feature on the documentation page, the top results for "layers" all refer to the these levels of configuration while a search for "scope" returns only results not related to this concept at all 🤷‍♂️

You are absolutely right!
Please use the term 'layers'.

[tuxmea]

Layout issue with short list of data: