Get detailed formats from engines (#38)

* Add get_detected_gpus() and supported_render_engines() to Blender class

* Parse help args for Blender

* Return dict instead of list

* Parse args for FFMPEG

* Add API to get renderer args

* Only return available renderers

* Parse help args for Blender

* Return dict instead of list

* Parse args for FFMPEG

* Rebase off master

* Rebase

* Change methods from class methods to instance methods

* FFMPEG format fetching

src/api_server.py

@@ -561,6 +561,15 @@ def delete_engine_download():
     return "Success" if delete_result else ("Error deleting requested engine", 500)
 
 
+@server.get('/api/renderer/<renderer>/args')
+def get_renderer_args(renderer):
+    try:
+        renderer_engine_class = RenderWorkerFactory.class_for_name(renderer).engine()
+        return renderer_engine_class.get_arguments()
+    except LookupError:
+        return f"Cannot find renderer '{renderer}'", 400
+
+
 @server.route('/upload')
 def upload_file_page():
     return render_template('upload.html', supported_renderers=RenderWorkerFactory.supported_renderers())