doc: updated README.md

README.md

@@ -15,6 +15,7 @@ thoroughly reviewed it, especially the system hardening and security tweaks that
 - ***gaming***: gaming on linux, e.g. Steam and Heroic Games Launcher.
 - ***security***: security-related softwares and tweaks, e.g. applying custom system limits, installing an antivirus.
 - ***server***: common tooling for servers, e.g. monitoring, altering, firewall rules.
+- ***workstation***: tooling and configuration for an X11 graphical workstation.
 
 # Usage
 ## Prerequisites
@@ -84,8 +85,6 @@ Execute a command using the Python wrapper that activates the virtualenv, e.g. `
 #### docker
 *build*: build all docker images available in `/images`, e.g. `task docker:build`
 
-*push*: push built images to docker hub, e.g. `task docker:push`
-
 #### module:<module_name>
 Directly execute a Python module located in `collections/ansible_collections/nullified/infrastructure/plugins/modules` with its default configuration
 (typically the path to a test YAML file). Used only for debugging purpose.
@@ -98,6 +97,9 @@ Useful to ensure playbooks behave as expected using a Docker container.
 #### test:modules
 Run Ansible's sanity tests on each collections declared in `collections/ansible_collections`.
 
+#### nosey
+Run `noseyparker`, a tool that aims to find potential data leak such as passwords and security token.
+
 ### Examples
 ```shell
 # encrypt vault
@@ -119,70 +121,16 @@ cd nullified/infrastructure/roles
 task venv -- ansible-galaxy collection init tooling
 ```
 
----
+## Advanced Configuration
+### Global variables
+Global variables are defined in `inventory/group_vars/all/vars.yml` and are used in multiple roles and playbooks.
+`dns.type`: what type of DNS configuration should be performed; also works as a selector for type related parameters;
+`dns.default`: default type of DNS configuration to setup; will use the corresponding `dns.<type>` dictionary retrieve corresponding data;
+`dns.udp`: IP addresses for basic DNS configuration;
+`dns.dot`: IP addresses for DNS-over-TLS configuration;
+`dns.doh`: IP addresses and HTTPS addresses for DNS-over-HTTPS configuration; 
 
-## Cheatsheet
-### Ansible usage
-```shell
-# validate files
-ansible-playbook --syntax-check <file>
-
-# gather facts of a docker container
-ansible <target> -m setup
-```
-
-```yaml
-# handlers
-# invoked by a task through `notify`, executed only if caller triggered a state change; runs at the end of the play in the order they are declared;
-
-# -> force handlers to run:
-- name: execute all handlers
-  meta: flush_handlers
-```
-
-***runtime grouping***
-```yaml
-name: coin
-hosts: all
-gather_facts: true
-tasks:
-  - name: group by OS
-    group_by:
-      key: "{{ ansible_facts.distribution }}"
-```
-
-***builtin vars***
-- hostvars: {hostname => kvp_vars, ...},
-- inventory_hostname(_short)?: name of current host,
-- group_names: list of groups assigned to current host,
-- groups: {groupname => [hostX, ...], ...},
-- ansible_check_mode: isRunningInCheckMode ?,
-- ansible_play_batch: list inventory hostnames active in current batch,
-- ansibble_play_hosts: ist inventory hostnames active in current play,
-
-### Python modules
-***argument options***
-> *NOTE*
-> Ansible Up and Running, page 503
-
-- *default*: default value if arg is required,
-- *choices*: list of possible values for an array arg,
-- *deprecated_aliases*: deprecate aliases; `dict(name, version, date, collection_name)`,
-- *aliases*: aliases for given argument,
-- *type*: arg type,
-- *elements*: set type of list elements if arg is array,
-- *fallback*: tuple of a lookup function and a list to pass to it,
-- *no_log*: mask arg value in logs for sensitive data,
-- *options*: complex args; create list of suboptions,
-- *mutually_exclusive*: list of mutually exclusive suboptions,
-- *required_together*: list of names of sub options,
-- *required_one_of*: list of required mutually exclusive suboptions,
-- *required_if*: sequence of sequences,
-- *required_by*: dic mapping option names to seqs of option names
-
----
-
-### Notes / Todo
+## Notes
 ***dir layout***
 - collections: ansible root dir for all collections to reside in;
 - images: docker images, mostly used for ansible-test / molecule;