We currently have a script named `patroni_barman_recover` in Patroni, which is intended to be used as a custom bootstrap method, or as a custom replica creation method.
Now there is need of one more Barman related script in Patroni to handle switching of config models in Barman upon `on_role_change` events.
However, instead of creating another Patroni script, let's say `patroni_barman_config_switch`, and duplicating a lot of logic in the code, we decided to refactor the code so:
* Instead of two separate scripts (`patroni_barman_recover` and `patroni_barman_config_switch`), we have a single script (`patroni_barman`) with 2 sub-commands (`recover` and `config-switch`)
This is the overview of changes that have been performed:
* File `patroni.scripts.barman_recover` has been removed, and its logic has been split into a few files:
* `patroni.scripts.barman.cli`: handles the entrypoint of the new `patroni_barman` command, exposing the argument parser and calling the appropriate functions depending on the sub-command
* `patroni.scripts.barman.utils`: implements utilitary enums, functions and classes wich can be used by `cli` and by sub-commands implementation:
* retry mechanism
* logging set up
* communication with pg-backup-api
* `patroni.scripts.barman.recover`: implements the `recover` sub-command only
* File `patroni.tests.test_barman_recover` has been renamed as `patroni.tests.test_barman`
* File `patroni.scripts.barman.config_switch` was created to implement the `config-switch` sub-command only
* `setup.py` has been changed so it generates a `patroni_barman` application instead of `patroni_barman_recover`
* Docs and unit tests were updated accordingly
References: PAT-154.
