Publish constants metadata to API (#19143)

* Publish metadata

* Ensure content is sorted

lib/python/qmk/cli/generate/api.py

@@ -18,6 +18,23 @@
 BUILD_API_PATH = Path('.build/api_data/')
 
 
+def _list_constants(output_folder):
+    """Produce a map of available constants
+    """
+    ret = {}
+    for file in (output_folder / 'constants').glob('**/*_[0-9].[0-9].[0-9].json'):
+        name, version = file.stem.rsplit('_', 1)
+        if name not in ret:
+            ret[name] = []
+        ret[name].append(version)
+
+    # Ensure content is sorted
+    for name in ret:
+        ret[name] = sorted(ret[name])
+
+    return ret
+
+
 def _resolve_keycode_specs(output_folder):
     """To make it easier for consumers, publish pre-merged spec files
     """
@@ -69,6 +86,7 @@ def generate_api(cli):
     keyboard_list_file = v1_dir / 'keyboard_list.json'  # A simple list of keyboard targets
     keyboard_aliases_file = v1_dir / 'keyboard_aliases.json'  # A list of historical keyboard names and their new name
     keyboard_metadata_file = v1_dir / 'keyboard_metadata.json'  # All the data configurator/via needs for initialization
+    constants_metadata_file = v1_dir / 'constants_metadata.json'  # Metadata for available constants
     usb_file = v1_dir / 'usb.json'  # A mapping of USB VID/PID -> keyboard target
 
     if BUILD_API_PATH.exists():
@@ -132,10 +150,12 @@ def generate_api(cli):
     keyboard_list_json = json.dumps({'last_updated': current_datetime(), 'keyboards': keyboard_list}, cls=InfoJSONEncoder)
     keyboard_aliases_json = json.dumps({'last_updated': current_datetime(), 'keyboard_aliases': keyboard_aliases}, cls=InfoJSONEncoder)
     keyboard_metadata_json = json.dumps(keyboard_metadata, cls=InfoJSONEncoder)
+    constants_metadata_json = json.dumps({'last_updated': current_datetime(), 'constants': _list_constants(v1_dir)})
 
     if not cli.args.dry_run:
         keyboard_all_file.write_text(keyboard_all_json)
         usb_file.write_text(usb_json)
         keyboard_list_file.write_text(keyboard_list_json)
         keyboard_aliases_file.write_text(keyboard_aliases_json)
         keyboard_metadata_file.write_text(keyboard_metadata_json)
+        constants_metadata_file.write_text(constants_metadata_json)