--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/libervia/web/server/tasks/implicit/task_sass.py	Fri Jun 02 16:49:28 2023 +0200
@@ -0,0 +1,69 @@
+#!/ur/bin/env python3
+
+import json
+from libervia.backend.core.log import getLogger
+from libervia.backend.core import exceptions
+from libervia.web.server.tasks import task
+
+
+log = getLogger(__name__)
+
+SASS_SUFFIXES = ('.sass', '.scss')
+
+
+class Task(task.Task):
+    """Compile .sass and .scss files found in themes browser paths"""
+    AFTER = ['js_modules']
+
+    async def prepare(self):
+        # we look for any Sass file, and cancel this task if none is found
+        sass_dirs = set()
+        for browser_path in self.resource.browser_modules.get('themes_browser_paths', []):
+            for p in browser_path.iterdir():
+                if p.suffix in SASS_SUFFIXES:
+                    sass_dirs.add(browser_path)
+                    break
+
+        if not sass_dirs:
+            raise exceptions.CancelError("No Sass file found")
+
+        # we have some Sass files, we need to install the compiler
+        d_path = self.resource.dev_build_path
+        package_path = d_path / "package.json"
+        try:
+            with package_path.open() as f:
+                package = json.load(f)
+        except FileNotFoundError:
+            package = {}
+        except Exception as e:
+            log.error(f"Unexepected exception while parsing package.json: {e}")
+
+        if 'node-sass' not in package.setdefault('dependencies', {}):
+            package['dependencies']['node-sass'] = 'latest'
+            with package_path.open('w') as f:
+                json.dump(package, f, indent=4)
+
+        cmd = self.find_command('yarnpkg', 'yarn')
+        await self.runCommand(cmd, 'install', path=str(d_path))
+
+        self.WATCH_DIRS = list(sass_dirs)
+
+    async def on_dir_event(self, host, filepath, flags):
+        if filepath.suffix in SASS_SUFFIXES:
+            await self.manager.run_task_instance(self)
+
+    async def start(self):
+        d_path = self.resource.dev_build_path
+        node_sass = d_path / 'node_modules' / 'node-sass' / 'bin' / 'node-sass'
+        for browser_path in self.resource.browser_modules['themes_browser_paths']:
+            for p in browser_path.iterdir():
+                if p.suffix not in SASS_SUFFIXES:
+                    continue
+                await self.runCommand(
+                    str(node_sass),
+                    "--omit-source-map-url",
+                    "--output-style", "compressed",
+                    "--output", str(self.build_path),
+                    str(p),
+                    path=str(self.build_path)
+                )