create backend addon documentation

docs/developer-guide/create-a-backend-add-on.md

@@ -12,10 +12,220 @@ myst:
 # Create a backend add-on
 
 This section explains how a developer can create an {term}`add-on` for the Plone backend.
-You will use a framework called {term}`GenericSetup` and a tool called {term}`Buildout`.
 
-```{note}
-This section for Plone 6 is in the process of being written.
-Until it is complete, Plone 5 documentation is the authoritative source.
-{doc}`plone5:develop/addons/components/genericsetup` (Plone 5)
+## System requirements
+
+Follow the section {ref}`create-project-cookieplone-system-requirements` to set up your system.
+
+## Generate the add-on project with `cookieplone`
+
+To develop an add-on for backend and/or Classic-UI, run the following command to generate your add-on project using the `backend_addon` Cookieplone template.
+See {doc}`plone:install/create-project-cookieplone` for details of the latter scenario.
+The following output assumes the former scenario.
+
+```shell
+uvx cookieplone backend_addon
+```
+
+```console
+> uvx cookieplone backend_addon
+╭──────────────────────────────── cookieplone ─────────────────────────────────╮
+│                                                                              │
+│                                   *******                                    │
+│                               ***************                                │
+│                             ***             ***                              │
+│                           ***    ***          ***                            │
+│                          ***    *****          ***                           │
+│                         ***      ***            ***                          │
+│                         ***               ***   ***                          │
+│                         ***              *****  ***                          │
+│                         ***      ***      ***   ***                          │
+│                          ***    *****          ***                           │
+│                           ***    ***          ***                            │
+│                             ***             ***                              │
+│                               ***************                                │
+│                                   *******                                    │
+│                                                                              │
+╰──────────────────────────────────────────────────────────────────────────────╯
+You've downloaded /Users/<username>/.cookiecutters/cookieplone-templates before. Is
+it okay to delete and re-download it? [y/n] (y):
+╭──────────────────────────────── Plone Addon ─────────────────────────────────╮
+│                                                                              │
+│ Creating a new Plone Addon                                                   │
+│                                                                              │
+│ Sanity check results:                                                        │
+│                                                                              │
+│   - Cookieplone: ✓                                                           │
+│   - uv: ✓                                                                    │
+│   - git: ✓                                                                   │
+│                                                                              │
+╰──────────────────────────────────────────────────────────────────────────────╯
+  [1/10] Addon Title (Addon):
+  [2/10] A short description of your addon (A new addon for Plone):
+  [3/10] Author (Plone Community):
+  [4/10] Author E-mail (collective@plone.org):
+  [5/10] GitHub Username or Organization (collective):
+  [6/10] Should we use prerelease versions? (No):
+  [7/10] Plone Version (6.1.3):
+  [8/10] Python package name (collective.addon):
+  [9/10] Support headless Plone?
+    1 - Yes
+    2 - No
+    Choose from [1/2] (1):
+  [10/10] Would you like to add a documentation scaffold to your project?
+    1 - Yes
+    2 - No
+    Choose from [1/2] (1):
+ -> Remove files used in classic UI setup
+ -> Create namespace packages
+ -> Format code
+ -> Initialize Git repository
+ -> Generate documentation scaffold
+╭────────────────────────── New addon was generated ───────────────────────────╮
+│                                                                              │
+│ Addon                                                                        │
+│                                                                              │
+│ Now, enter the repository, start coding, and push to your organization.      │
+│                                                                              │
+│ Sorry for the convenience,                                                   │
+│ The Plone Community.                                                         │
+│                                                                              │
+│ https://plone.org/                                                           │
+╰──────────────────────────────────────────────────────────────────────────────╯
+```
+
+Cookieplone creates a folder with the name of the add-on, in this example, `collective.addon`.
+
+You can now continue to add subtemplates to your addon {ref}`create-a-backend-add-on-add-subtemplate-label`
+
+
+## Generate the add-on project with `plonecli`
+
+Run the following command to create an addon project with `plonecli`
+
+```shell
+uvx plonecli create addon <addon namespace package>
+```
+
+```console
+> uvx plonecli create addon collective.addon
+RUN: bobtemplates.plone:addon -O collective.addon
+
+Welcome to mr.bob interactive mode. Before we generate directory structure,
+some questions need to be answered.
+
+Answer with a question mark to display help.
+Values in square brackets at the end of the questions show the default value if
+there is no answer.
+
+
+--> Package description [An add-on for Plone]:
+
+--> Plone version [6.0.0]:
+
+--> Python version for virtualenv [python3]:
+
+--> Do you want me to activate VS Code support? (y/n) [y]:
+
+
+
+isort-apply: successful:
+isort-apply: install_deps> python -I -m pip install isort -c constraints.txt
+isort-apply: commands[0]> isort /Users/<username>/Development/collective.addon/src
+/Users/<username>/Development/collective.addon/setup.py
+Fixing /Users/<username>/Development/collective.addon/src/collective/addon/testing.py
+Fixing /Users/<username>/Development/collective.addon/src/collective/addon/tests/test_setup.py
+  isort-apply: OK (2.57=setup[1.94]+cmd[0.63] seconds)
+  congratulations :) (2.59 seconds)
+
+
+Identified `/` as project root containing a file system root.
+Sources to be formatted: "Users/<username>/Development/collective.addon/src",
+  "Users/<username>/Development/collective.addon/setup.py"
+src/collective/__init__.py wasn't modified on disk since last run.
+src/collective/addon/browser/__init__.py wasn't modified on disk since last run.
+src/collective/addon/locales/__init__.py wasn't modified on disk since last run.
+src/collective/addon/tests/__init__.py wasn't modified on disk since last run.
+src/collective/addon/interfaces.py already well formatted, good job.
+reformatted src/collective/addon/__init__.py
+reformatted src/collective/addon/setuphandlers.py
+reformatted src/collective/addon/testing.py
+reformatted setup.py
+reformatted src/collective/addon/locales/update.py
+reformatted src/collective/addon/tests/test_setup.py
+
+All done! ✨ 🍰 ✨
+6 files reformatted, 5 files left unchanged.
+
+black-enforce: successful:
+black-enforce: install_deps> python -I -m pip install black -c constraints.txt
+black-enforce: commands[0]> black -v src setup.py
+  black-enforce: OK (2.60=setup[2.12]+cmd[0.48] seconds)
+  congratulations :) (2.61 seconds)
+
+
+git init is disabled!
+Generated file structure at /Users/<username>/Development/collective.addon/collective.addon
+```
+
+Plonecli creates a folder with the name of the add-on, in this example, `collective.addon`.
+
+You can now continue to add subtemplates to your addon {ref}`create-a-backend-add-on-add-subtemplate-label`
+
+
+(create-a-backend-add-on-add-subtemplate-label)=
+
+## Add `plonecli` subtemplate to an addon
+
+The generated addon contains a {file}`bobtemplates.cfg` file which lets you add several subtemplates with `plonecli`.
+
+Run the following command to list the available subtemplates.
+
+```shell
+uvx plonecli -l
 ```
+
+```shell
+> uvx plonecli -l
+Available mr.bob templates:
+ - addon
+  - behavior
+  - content_type
+  - controlpanel
+  - form
+  - indexer
+  - mockup_pattern
+  - portlet
+  - restapi_service
+  - site_initialization
+  - subscriber
+  - svelte_app
+  - theme
+  - theme_barceloneta
+  - theme_basic
+  - upgrade_step
+  - view
+  - viewlet
+  - vocabulary
+ - buildout
+ ```
+
+ All templates below `addon` can be added to your newly created addon with:
+
+ ```shell
+ uvx ploncli add <subtemplate>
+ ```
+
+Currently documented subtemplates:
+
+- behavior: {ref}`backend-behaviors-label`
+- content_type: {ref}`creating-content-types-label`
+- controlpanel: {ref}`control-panels-label`
+- form: {reg}`forms-label`
+- mockup_pattern: {ref}`mockup-and-patternslib-label`
+- theme_barceloneta: {ref}`create-a-theme-add-on-label`
+
+
+The addon also contains a {term}`GenericSetup` default install/uninstall profile.
+
+See {ref}`genericsetup-label` for more information.