Add a new socle PostgresSQL addon

Problem

I started to integrate keycloak-x as a replacement for the actual keycloak and found that the keycloak-x codecentric chart does not include a PostgreSQL subchart.

We need to provide a socle addon to install a PostgreSQL to be used, preferably by all addons.

Proposal

• new socle addon postgresql using bitnami chart
• centralised postgresql configuration for either external or addon provided database
• tools to create per addon user and database

Use external PostgreSQL

Do not ask for PostgreSQL installation and provide address/port configuration:

[postgresql]
install=false
address=postgres.example.net
port=5432
adminUser=changeme
adminPassword=changeme

Use internal addon

[postgresql]
install=true
namespace=laboite-postgresql
# address=automatically calculated
# port=automatically calculated
adminUser=changeme
adminPassword=changeme

Open questions

• Is it meaningful to default the namespace to {{ [general][namespace] }}-postgresql?
• Provide an easier way for addons to override parameters, for example, the following example is quite difficult to read:

  database:
    vendor: postgres
    {%- if config['postgresql']['install'] %}
    hostname: {{ 'postgres' ~ config['postgresql']['namespace'] | tojson }}
    port: {{ config['postgres']['port'] | default('5432', true) | tojson }}
    {%- else %}
    hostname: {{ config['keycloak']['postgresAddress'] | default(config['postgresql']['address'], true) | tojson }}
    port: {{ config['keycloak']['postgresPort'] | default(config['postgresql'][port], true) | tojson }}
    {%- endif %}