hiera.yaml without datadir explicitly set causes an error upon selecting a node

[tuxmea]

Fresh installation of container v1.2.0

• Create admin - OK
• Crate User - OK
• Login as User - OK
• Select environment - OK
• Select node - ERROR

Internal Server Error
If you are the administrator of this server, please check the hdm log file for the full error message.

In case the issue persists, please consider opening an issue here: https://github.com/betadots/hdm/issues/new

Reason: hiera.yaml has no default datadir set:

---
version: 5
defaults:
  # The default value for "datadir" is "data" under the same directory as the hiera.yaml
  # file (this file)
  # When specifying a datadir, make sure the directory exists.
  # See https://puppet.com/docs/puppet/latest/environments_about.html for further details on environments.
  # datadir: data
  # data_hash: yaml_data
hierarchy:
  - name: "Per-node data (yaml version)"
    path: "nodes/%{::trusted.certname}.yaml"
  - name: "Other YAML hierarchy levels"
    paths:
      - "common.yaml"

Docker logs:

I, [2023-10-13T13:25:07.432133 #24]  INFO -- : [1e457829-75f1-41e6-8242-2cdc207bc17e] Started GET "/environments/production/nodes/puppet.enterprise.betadots.training/keys" for 10.200.20.1 at 2023-10-13 13:25:07 +0000
I, [2023-10-13T13:25:07.433086 #24]  INFO -- : [1e457829-75f1-41e6-8242-2cdc207bc17e] Processing by KeysController#index as HTML
I, [2023-10-13T13:25:07.433178 #24]  INFO -- : [1e457829-75f1-41e6-8242-2cdc207bc17e]   Parameters: {"environment_id"=>"production", "node_id"=>"puppet.enterprise.betadots.training"}
I, [2023-10-13T13:25:07.525811 #24]  INFO -- : [1e457829-75f1-41e6-8242-2cdc207bc17e] Completed 500 Internal Server Error in 93ms (ActiveRecord: 0.5ms | Allocations: 9635)
F, [2023-10-13T13:25:07.526421 #24] FATAL -- : [1e457829-75f1-41e6-8242-2cdc207bc17e]   
[1e457829-75f1-41e6-8242-2cdc207bc17e] NoMethodError (undefined method `merge' for nil:NilClass):
[1e457829-75f1-41e6-8242-2cdc207bc17e]   
[1e457829-75f1-41e6-8242-2cdc207bc17e] app/models/hiera_data/config.rb:33:in `block in initialize_hierarchies'
[1e457829-75f1-41e6-8242-2cdc207bc17e] app/models/hiera_data/config.rb:31:in `map'
[1e457829-75f1-41e6-8242-2cdc207bc17e] app/models/hiera_data/config.rb:31:in `initialize_hierarchies'
[1e457829-75f1-41e6-8242-2cdc207bc17e] app/models/hiera_data/config.rb:8:in `initialize'
[1e457829-75f1-41e6-8242-2cdc207bc17e] app/models/hiera_data.rb:141:in `new'
[1e457829-75f1-41e6-8242-2cdc207bc17e] app/models/hiera_data.rb:141:in `config'
[1e457829-75f1-41e6-8242-2cdc207bc17e] app/models/hiera_data.rb:28:in `all_keys'
[1e457829-75f1-41e6-8242-2cdc207bc17e] app/models/key.rb:8:in `all_for'
[1e457829-75f1-41e6-8242-2cdc207bc17e] app/controllers/keys_controller.rb:10:in `index'

[oneiros]

This was a tricky one: The problem was not that datadir was missing. We get all the defaults directly from puppet/hiera and datadir is one of them.

The problem was, that this hiera.yaml includes the key defaults, but leaves it completely empty. We take the defaults from hiera and merge them with the defaults from hiera.yaml, so those take precedence. But in this case, the yaml parser will parse this as {defaults: nil} and, as it turns out, this overwrites the hiera defaults completely when merging.

I prepared a fix in #212