Automatically download labvariables CSS instead of shipping them

.gitignore

@@ -32,6 +32,12 @@ package-lock.json
 share/jupyter/voila/templates/base/static/*voila.js
 share/jupyter/voila/templates/base/static/*[woff|woff2|eot|svg]
 
+share/jupyter/voila/templates/classic/static/labvariables.css
+share/jupyter/voila/templates/classic/static/materialcolors.css
+
+share/jupyter/voila/templates/reveal/static/labvariables.css
+share/jupyter/voila/templates/reveal/static/materialcolors.css
+
 lib
 
 voila/labextension
@@ -40,4 +46,4 @@ tsconfig.tsbuildinfo
 ui-tests/playwright-report
 ui-tests/test-results
 ui-tests/benchmark-results
-ui-tests/jlab_root
+ui-tests/jlab_root

setup.cfg

@@ -56,3 +56,10 @@ test =
 [options.entry_points]
 console_scripts =
     voila = voila.app:main
+
+[check-manifest]
+ignore =
+    share/jupyter/voila/templates/classic/static/labvariables.css
+    share/jupyter/voila/templates/classic/static/materialcolors.css
+    share/jupyter/voila/templates/reveal/static/labvariables.css
+    share/jupyter/voila/templates/reveal/static/materialcolors.css

setup.py

@@ -7,8 +7,10 @@
 # The full license is in the file LICENSE, distributed with this software.  #
 #############################################################################
 from pathlib import Path
-
+from urllib.request import urlopen
 import setuptools
+import sys
+import os
 
 HERE = Path(__file__).parent.resolve()
 
@@ -47,13 +49,87 @@
     ("share/jupyter/voila/templates", "share/jupyter/voila/templates", "**/*[!.map]"),
 ]
 
+
+jupyterlab_apputils_version = "3.2.8"
+jupyterlab_theme_light_version = "3.2.8"
+
+css_files = [
+    (
+        "https://unpkg.com/@jupyterlab/apputils@%s/style/materialcolors.css"
+        % jupyterlab_apputils_version,
+        "materialcolors.css",
+    ),
+    (
+        "https://unpkg.com/@jupyterlab/theme-light-extension@%s/style/variables.css"
+        % jupyterlab_theme_light_version,
+        "labvariables.css",
+    ),
+]
+
+
+class FetchCSS(setuptools.Command):
+    """Fetch CSS files from the CDNs."""
+
+    description = "Fetch CSS from CDN"
+    user_options = []
+
+    def initialize_options(self):
+        pass
+
+    def finalize_options(self):
+        pass
+
+    def run(self):
+        for template_name in ["classic", "reveal"]:
+            for url, filename in css_files:
+                directory = os.path.join(
+                    "share", "jupyter", "voila", "templates", template_name, "static"
+                )
+                dest = os.path.join(directory, filename)
+                if not os.path.exists(directory):
+                    os.makedirs(directory)
+                if not os.path.exists(".git") and os.path.exists(dest):
+                    # not running from git, nothing to do
+                    return
+                print("Downloading CSS: %s" % url)
+                try:
+                    css = urlopen(url).read()
+                except Exception as e:
+                    msg = "Failed to download css from %s: %s" % (url, e)
+                    print(msg, file=sys.stderr)
+
+                    if os.path.exists(dest):
+                        print("Already have CSS: %s, moving on." % dest)
+                    else:
+                        raise OSError("Need CSS to proceed.")
+                    return
+
+                with open(dest, "wb") as f:
+                    f.write(css)
+                print("Downloaded Notebook CSS to %s" % dest)
+
+
+def download_css_first(command):
+    class CSSFirst(command):
+        def run(self):
+            self.distribution.run_command("download_css")
+            return command.run(self)
+
+    return CSSFirst
+
+
 try:
     from jupyter_packaging import wrap_installers, npm_builder, get_data_files
 
     # In develop mode, just run yarn
     builder = npm_builder(build_cmd="build", npm="jlpm", force=True)
     cmdclass = wrap_installers(post_develop=builder, ensured_targets=ensured_targets)
 
+    cmdclass["download_css"] = FetchCSS
+    cmdclass["develop"] = download_css_first(cmdclass["develop"])
+    cmdclass["sdist"] = download_css_first(cmdclass["sdist"])
+    cmdclass["bdist_wheel"] = download_css_first(cmdclass["bdist_wheel"])
+
     setup_args = dict(cmdclass=cmdclass, data_files=get_data_files(data_files_spec))
 except ImportError:
     setup_args = dict()