data/gnome: add a quick and dirty SVG checker for the GNOME SVGs

Checks for the three layers we need and that any buttons in the files are
consecutive and have the right layers

Fixes #196

Co-authored-by: Jente Hidskes <hjdskes@gmail.com>

circle.yml

@@ -56,7 +56,7 @@ libratbag_references:
 fedora_install: &fedora_install
   run:
     name: Install prerequisites
-    command: dnf install -y tree git gcc gcc-c++ meson check-devel libudev-devel libevdev-devel doxygen graphviz valgrind python3-gobject python3-evdev glib2-devel
+    command: dnf install -y tree git gcc gcc-c++ meson check-devel libudev-devel libevdev-devel doxygen graphviz valgrind python3-gobject python3-evdev glib2-devel python3-lxml
 
 
 fedora_settings: &fedora_settings
@@ -81,7 +81,7 @@ ubuntu_settings: &ubuntu_settings
           apt-get install -y software-properties-common
           add-apt-repository universe
           apt-get update
-          apt-get install -y tree git gcc g++ pkg-config meson check libudev-dev libevdev-dev libsystemd-dev doxygen graphviz valgrind python3-gi python3-evdev libglib2.0-dev:
+          apt-get install -y tree git gcc g++ pkg-config meson check libudev-dev libevdev-dev libsystemd-dev doxygen graphviz valgrind python3-gi python3-evdev libglib2.0-dev python3-lxml
     - checkout
     - *start_dbus
     - *build_and_test

data/gnome/check-svg.py

@@ -0,0 +1,118 @@
+#!/usr/bin/python3
+# vim: set expandtab shiftwidth=4 tabstop=4:
+
+import sys
+from lxml import etree
+import logging
+
+ns = {'svg': 'http://www.w3.org/2000/svg'}
+style_query = '//svg:rect[@id=\"{}\"][contains(@style, \"{}\")]'
+
+logger = None
+
+class SVGLogger(logging.Logger):
+    def __init__(self, name, level=logging.NOTSET):
+        self.success = True
+        return super().__init__(name, level)
+
+    def error(self, msg, *args, **kwargs):
+        self.success = False
+        return super().error(msg, *args, **kwargs)
+
+    @classmethod
+    def get_logger(cls, path):
+        logging.setLoggerClass(SVGLogger)
+        logging.basicConfig(level=logging.DEBUG)
+        return logging.getLogger(path)
+
+
+def check_size(root):
+    width = float(root.attrib['width'])
+    height = float(root.attrib['height'])
+    if not 400 < width < 500:
+        logger.error("Width is outside of range: {}".format(width))
+    if not 400 < height < 500:
+        logger.error("Height is outside of range: {}".format(height))
+
+
+def check_layers(root):
+    """
+    Check there are layers (well, groups) for the components we require.
+    """
+    layer_ids = [g.attrib['id'] for g in root.iterfind('svg:g', ns)]
+
+    for layer in ["Device", "Buttons", "LEDs"]:
+        if layer not in layer_ids:
+            logger.error("Missing layer: {}".format(layer))
+
+
+def check_elements(root, prefix, required=0):
+    """
+    Checks for elements of the form 'prefixN' in the root tag. Any elements
+    found must be consecutive or an error is printed, i.e. if there's a
+    'button8' there has to be a 'button7'.
+
+    If required is nonzero, an error is logged for any missing element with
+    an index less than required.
+    """
+
+    # elements can be paths and rects
+    # This includes leaders and lines
+    element_ids = [p.attrib['id'] for p in root.xpath('//svg:path', namespaces=ns) if p.attrib['id'].startswith(prefix)]
+    element_ids += [p.attrib['id'] for p in root.xpath('//svg:rect', namespaces=ns) if p.attrib['id'].startswith(prefix)]
+    element_ids += [g.attrib['id'] for g in root.xpath('//svg:g', namespaces=ns) if g.attrib['id'].startswith(prefix)]
+
+    idx = 0
+    highest = -1
+    for idx in range(0, 20):
+        e = '{}{}'.format(prefix, idx)
+        if e in element_ids:
+            highest = idx
+            previous = '{}{}'.format(prefix, idx - 1)
+            if idx > 0 and previous not in element_ids:
+                logger.error("Non-consecutive {}: {}".format(prefix, e))
+
+            leader = '{}{}-leader'.format(prefix, idx)
+            if leader not in element_ids:
+                logger.error("Missing {} for {}".format(leader, e))
+            else:
+                element = root.xpath(style_query.format(leader, 'text-align'), namespaces=ns)
+                if element is None or len(element) != 1 or element[0] is None:
+                    logger.error("Missing style property for {}".format(leader))
+
+            path = '{}{}-path'.format(prefix, idx)
+            if path not in element_ids:
+                logger.error("Missing {} for {}".format(path, e))
+        elif idx < required:
+            logger.error("Missing {}: {}".format(prefix, e))
+
+    logger.info("Found {} {}s".format(highest + 1, prefix))
+
+
+def check_leds(root):
+    check_elements(root, "led")
+
+
+def check_buttons(root):
+    check_elements(root, "button", 3)
+
+
+def check_svg(path):
+    svg = etree.parse(path)
+    root = svg.getroot()
+
+    check_size(root)
+    check_layers(root)
+    check_buttons(root)
+    check_leds(root)
+
+if __name__ == "__main__":
+    success = True
+    for path in sys.argv[1:]:
+        logger = SVGLogger.get_logger(path)
+        check_svg(path)
+        if not logger.success:
+            success = False
+
+    if not success:
+        sys.exit(1)

meson.build

@@ -306,7 +306,7 @@ default_svg_files = [
 install_data(default_svg_files,
 	     install_dir : join_paths(get_option('datadir'), 'libratbag', 'default'))
 
-gnome_svg_files = [
+gnome_svg_files = files(
 	'data/gnome/fallback.svg',
 	'data/gnome/logitech-g303.svg',
 	'data/gnome/logitech-g403.svg',
@@ -316,10 +316,13 @@ gnome_svg_files = [
 	'data/gnome/logitech-g700.svg',
 	'data/gnome/logitech-g900.svg',
 	'data/gnome/roccat-kone-xtd.svg',
-]
+)
 install_data(gnome_svg_files,
 	     install_dir : join_paths(get_option('datadir'), 'libratbag', 'gnome'))
 
+test_svg_files = find_program('data/gnome/check-svg.py')
+test('check-svg', test_svg_files, args : gnome_svg_files)
+
 #### tests ####
 enable_tests = get_option('enable-tests')
 if enable_tests