Adapt set-kodi-display to KODI 18 final

Manual.org

@@ -6028,104 +6028,7 @@ This systemd unit for the user session starts (and stops) kodi.
 #+INCLUDE: "roles/kodi/templates/kodi.service.j2" src conf
 **** set-kodi-diplay
 This is a version-dependent script to force KODI to use the display set by the environment variable ~DISPLAY~. The following Version is intended for KODI 18.
-#+BEGIN_SRC jinja2 :tangle roles/kodi/templates/set-kodi-display.j2 :padline no
+#+INCLUDE: "roles/kodi/templates/set-kodi-display.j2" src python
-#!/usr/bin/env python3
-"""
-{{ ansible_managed }}
-
-This Script changes the monitor in KODI's guisettings.xml to the wanted output
-according to the DISPLAY environment variable. It works with KODI 18 (not KODI 17!).
-"""
-
-import os
-import sys
-import subprocess
-import xml.etree.ElementTree as ET
-
-
-GUISETTINGS = '/var/lib/vdr/.kodi/userdata/guisettings.xml'
-CACHE_DIR = '/var/lib/vdr/.kodi/.display_cache'
-VIDEOSCREEN_TEMPLATE = """<settings version="2">
-    <setting id="videoscreen.monitor" default="true">{}</setting>
-</settings>"""
-
-
-def get_output_names():
-    """
-    get display name from xrandr output for given DISPLAY environment variable
-    """
-    xrandr_output = [
-        l for l in subprocess.check_output(
-            ["xrandr"],
-            env={"DISPLAY": os.environ["DISPLAY"]}
-        ).decode("utf-8").splitlines()
-    ]
-    return [l.split()[0] for l in xrandr_output if " connected " in l]
-
-
-def parse_template(template_path, template, output=""):
-    """read videoscreen settings from backup or create a stub file"""
-    try:
-        xml_tree = ET.parse(template_path)
-    except FileNotFoundError:
-        print("{} not found, creating stub file".format(template_path))
-        xml_template = ET.fromstring(template.format(output))
-        xml_tree = ET.ElementTree(xml_template)
-    finally:
-        xml_tree.write(template_path)
-    return xml_tree
-
-
-def backup_videoscreen():
-    """parse guisettings.xml for display name an backup videoscreen data"""
-    tree = parse_template(GUISETTINGS, VIDEOSCREEN_TEMPLATE, "Default")
-    root = tree.getroot()
-    videoscreen = root.find("./setting[@id='videoscreen.monitor']")
-    output = videoscreen.text
-    xml_path = os.path.join(CACHE_DIR, '{}-videodevice.xml'.format(output))
-    base_tree = ET.fromstring('<settings version="2"></settings>')
-    xml_tree = ET.ElementTree(base_tree)
-    backup_root = xml_tree.getroot()
-    backup_root.insert(0, videoscreen)
-    xml_tree.write(xml_path)
-    print("written backup for {} to {}".format(output, xml_path))
-
-
-def change_videoscreen(output, new_videoscreen):
-    """change videoscreen node to content of backup file"""
-    tree = parse_template(GUISETTINGS, VIDEOSCREEN_TEMPLATE, output)
-    root = tree.getroot()
-
-    videoscreen = root.find('./setting[@id="videoscreen.monitor"]')
-    if videoscreen is not None:
-        videoscreen.text = new_videoscreen.text
-    else:
-        videoscreen = root.find("./settings")
-        root.insert(0, new_videoscreen)
-    tree.write(GUISETTINGS)
-    return tree
-
-if __name__ == '__main__':
-    output = get_output_names()[0]
-    if not output:
-        sys.exit("Error: no screen name found")
-    try:
-        os.makedirs(CACHE_DIR, exist_ok=True)
-    except PermissionError:
-        sys.exit("Error: insufficient permissions to create cachedir {}".format(
-            CACHE_DIR))
-    try:
-        backup_videoscreen()
-    except FileNotFoundError:
-        print("{} does not exist".format(GUISETTINGS))
-    except Exception as e:
-        print("Could not backup videoscreen.monitor:", str(e))
-    xml_path = os.path.join(CACHE_DIR, '{}-videodevice.xml'.format(output))
-    videodir_xml = parse_template(xml_path, VIDEOSCREEN_TEMPLATE, output)
-    videodir_root = videodir_xml.getroot()
-    new_videoscreen = videodir_root.find("./setting[@id='videoscreen.monitor']")
-    guisettings_xml = change_videoscreen(output, new_videoscreen)
-#+END_SRC
 *** files
 :PROPERTIES:
 :ID:       58c5c693-bd24-420a-bfed-79771e8e0d47

roles/kodi/tasks/install-kodi.yml

@@ -5,6 +5,7 @@
     name:
       - kodi
       - kodi-pvr-vdr-vnsi
+      - python3-lxml
     state: present
     install_recommends: no
 

roles/kodi/templates/set-kodi-display.j2

@@ -4,40 +4,64 @@
 
 This Script changes the monitor in KODI's guisettings.xml to the wanted output
 according to the DISPLAY environment variable. It works with KODI 18 (not KODI 17!).
+
+In order to change the display we need to modify the settings/videoscreen nodes.
+
+Basic algorithm:
+    - get the current videoscreen.monitor
+    - check if it needs to be changed
+    - create a backup of the videoscreen nodes in /var/lib/vdr/.kodi/.display_cache/{CONNETOR}-videoscreen.xml
+    - check if there is an existing backup for the new CONNECTOR
+    - parse the backup of the videoscreen nodes
+    - replace the videoscreen nodes with the backup data
 """
 
+import copy
 import os
 import sys
 import subprocess
-import xml.etree.ElementTree as ET
+from lxml import etree as ET
 
 
 GUISETTINGS = '/var/lib/vdr/.kodi/userdata/guisettings.xml'
 CACHE_DIR = '/var/lib/vdr/.kodi/.display_cache'
 VIDEOSCREEN_TEMPLATE = """<settings version="2">
-    <setting id="videoscreen.monitor" default="true">{}</setting>
+    <setting id="videoscreen.monitor">{}</setting>
 </settings>"""
 
 
-def get_output_names():
+def create_cache_dir():
+    try:
+        os.makedirs(CACHE_DIR, exist_ok=True)
+    except PermissionError:
+        sys.exit(f"Error: insufficient permissions to create cachedir {CACHE_DIR}")
+    except Exception as e:
+        sys.exit(f"Unexpected Error when trying to create {CACHE_DIR}:", e)
+
+
+
+def get_output_name():
     """
     get display name from xrandr output for given DISPLAY environment variable
     """
-    xrandr_output = [
+    try:
-        l for l in subprocess.check_output(
+        xrandr_output = [
-            ["xrandr"],
+            l for l in subprocess.check_output(
-            env={"DISPLAY": os.environ["DISPLAY"]}
+                ["xrandr"],
-        ).decode("utf-8").splitlines()
+                env={"DISPLAY": os.environ["DISPLAY"]}
-    ]
+            ).decode("utf-8").splitlines()
-    return [l.split()[0] for l in xrandr_output if " connected " in l]
+        ]
+        return next(l.split()[0] for l in xrandr_output if " connected " in l)
+    except Exception as e:
+        sys.exit("could not determine output name", e)
 
 
 def parse_template(template_path, template, output=""):
     """read videoscreen settings from backup or create a stub file"""
     try:
         xml_tree = ET.parse(template_path)
-    except FileNotFoundError:
+    except OSError:
-        print("{} not found, creating stub file".format(template_path))
+        print(f"{template_path} not found, creating stub file", file=sys.stderr)
         xml_template = ET.fromstring(template.format(output))
         xml_tree = ET.ElementTree(xml_template)
     finally:
@@ -45,52 +69,49 @@ def parse_template(template_path, template, output=""):
     return xml_tree
 
 
-def backup_videoscreen():
+def main(output):
-    """parse guisettings.xml for display name an backup videoscreen data"""
+    guisettings = parse_template(GUISETTINGS, VIDEOSCREEN_TEMPLATE, "Default")
-    tree = parse_template(GUISETTINGS, VIDEOSCREEN_TEMPLATE, "Default")
+
-    root = tree.getroot()
+    # parse guisettings Etree for display name an backup videoscreen data
-    videoscreen = root.find("./setting[@id='videoscreen.monitor']")
+    root = guisettings.getroot()
-    output = videoscreen.text
+    old_output = root.find("./setting[@id='videoscreen.monitor']").text
-    xml_path = os.path.join(CACHE_DIR, '{}-videodevice.xml'.format(output))
+    if old_output == output:
+        print("no changes necessary, exiting", file=sys.stderr)
+        sys.exit()
+
+    # create a minimal guisettings etree
+    xml_path = os.path.join(CACHE_DIR, f'{old_output}-videoscreen.xml')
     base_tree = ET.fromstring('<settings version="2"></settings>')
     xml_tree = ET.ElementTree(base_tree)
     backup_root = xml_tree.getroot()
-    backup_root.insert(0, videoscreen)
+
+    # copy videoscreen elements to backup etree
+    videoscreen_elements = root.xpath(
+            "./setting[starts-with(@id, 'videoscreen.')]")
+    for element in videoscreen_elements:
+        backup_root.append(copy.deepcopy(element))
+        element.getparent().remove(element)
     xml_tree.write(xml_path)
-    print("written backup for {} to {}".format(output, xml_path))
+    print(f"written backup for {old_output} to {xml_path}", file=sys.stderr)
 
-
+    # change videoscreen node to content of backup file
-def change_videoscreen(output, new_videoscreen):
+    xml_path = os.path.join(CACHE_DIR, f'{output}-videoscreen.xml')
-    """change videoscreen node to content of backup file"""
-    tree = parse_template(GUISETTINGS, VIDEOSCREEN_TEMPLATE, output)
-    root = tree.getroot()
-
-    videoscreen = root.find('./setting[@id="videoscreen.monitor"]')
-    if videoscreen is not None:
-        videoscreen.text = new_videoscreen.text
-    else:
-        videoscreen = root.find("./settings")
-        root.insert(0, new_videoscreen)
-    tree.write(GUISETTINGS)
-    return tree
-
-if __name__ == '__main__':
-    output = get_output_names()[0]
-    if not output:
-        sys.exit("Error: no screen name found")
-    try:
-        os.makedirs(CACHE_DIR, exist_ok=True)
-    except PermissionError:
-        sys.exit("Error: insufficient permissions to create cachedir {}".format(
-            CACHE_DIR))
-    try:
-        backup_videoscreen()
-    except FileNotFoundError:
-        print("{} does not exist".format(GUISETTINGS))
-    except Exception as e:
-        print("Could not backup videoscreen.monitor:", str(e))
-    xml_path = os.path.join(CACHE_DIR, '{}-videodevice.xml'.format(output))
     videodir_xml = parse_template(xml_path, VIDEOSCREEN_TEMPLATE, output)
     videodir_root = videodir_xml.getroot()
-    new_videoscreen = videodir_root.find("./setting[@id='videoscreen.monitor']")
+    videoscreen = videodir_root.find("./setting[@id='videoscreen.monitor']")
-    guisettings_xml = change_videoscreen(output, new_videoscreen)
+    # copy videoscreen.* elements from Backup
+    videoscreen_elements = videodir_root.xpath(
+            "./setting[starts-with(@id, 'videoscreen.')]")
+    for element in videoscreen_elements:
+        new_element = copy.deepcopy(element)
+        root.append(new_element)
+    guisettings.write(GUISETTINGS)
+
+
+if __name__ == '__main__':
+    create_cache_dir()
+    output = get_output_name()
+    try:
+        main(output)
+    except Exception as e:
+        print("Could not change videoscreen.* settings:", str(e), file=sys.stderr)