doc: adapt RTD for direct sphinx-build instead of setuptools

Author: blackboxsw

.readthedocs.yaml

@@ -4,7 +4,19 @@ build:
   os: "ubuntu-22.04"
   tools:
     python: "3.10"
+  jobs:
+    pre_build:
+      - 'sudo apt update'
+      - 'sudo apt install meson'
+    build:
+      html:
+        - 'meson setup build_dir -Dreadthedocs_build=true -Dinit_system=systemd'
+        - 'meson compile -C build_dir'
+        - 'python3 -m sphinx -T -b html -d doc/rtd -D language=en . $READTHEDOCS_OUTPUT/html'
 
+
+sphinx:
+  configuration: doc/rtd/conf.py
 formats: all
 
 python:

doc-requirements.txt

@@ -1,9 +1,9 @@
 -r requirements.txt
 doc8
 furo
+meson
 m2r2
 pyyaml
-setuptools
 sphinx==7.1.2
 sphinx-design
 sphinx-copybutton

meson.build

@@ -7,15 +7,10 @@ project(
       'python.install_env=auto'
     ]
 )
-completions = dependency('bash-completion')
-systemd = dependency('systemd')
 system = host_machine.system()
 sysconfdir = get_option('sysconfdir')
 INIT_SYSTEM = get_option('init_system')
-VALID_INIT_SYSTEMS = [
-  'systemd', 'sysvinit', 'sysvinit_deb', 'sysvinit_dragonfly',
-  'sysvinit_freebsd', 'sysvinit_netbsd', 'sysvinit_openbsd'
-]
+VALID_INIT_SYSTEMS = ['systemd']
 if not VALID_INIT_SYSTEMS.contains(INIT_SYSTEM)
   error(
     'Invalid init_system supplied: "@0@". Must be one of: @1@'.format(
@@ -24,6 +19,7 @@ if not VALID_INIT_SYSTEMS.contains(INIT_SYSTEM)
 endif
 
 
+
 lib_exec_dir = join_paths('/usr', get_option('libexecdir'), 'cloud-init')
 
 pymod = import('python')
@@ -39,14 +35,19 @@ install_subdir(
 )
 
 # Binaries and script entrypoints
-bash_completions_dir = completions.get_variable(
-  pkgconfig: 'completionsdir',
-  default_value: '/etc/bash_completion.d'
-)
-install_data(
-  'bash_completion/cloud-init',
-  install_dir: bash_completions_dir, install_tag: 'scripts'
-)
+readthedocs = get_option('readthedocs_build')
+if not readthedocs
+  completions = dependency('bash-completion')
+  bash_completions_dir = completions.get_variable(
+    pkgconfig: 'completionsdir',
+    default_value: '/etc/bash_completion.d'
+  )
+  install_data(
+    'bash_completion/cloud-init',
+    install_dir: bash_completions_dir,
+    install_tag: 'scripts'
+  )
+endif
 
 install_data(
   ['tools/ds-identify', 'tools/hook-hotplug','tools/uncloud-init', 'tools/write-ssh-key-fingerprints' ],
@@ -81,6 +82,7 @@ install_data(
 )
 
 if INIT_SYSTEM == 'systemd'
+  systemd = dependency('systemd')
   udev = dependency('udev')
   systemd_unit_dir =  systemd.get_variable(pkgconfig: 'systemdsystemunitdir')
   systemd_generator_dir =  systemd.get_variable(