Python equivalent of command line panel serve

Panel
1

I started developing a template panel application (https://github.com/chime-experiment/bondia) using my_template.show(). Now I would like to deploy it somewhere and make it accessible via web for multiple users. Changing .show() to servable() and then passing the name of the script to panel serve my_script.py does exactly what I want.

But I am wondering if I can somehow get the same functionality just by changing my script and calling it directly. This is to make deployment and configuration a little bit less awkward.

I also couldn’t find a way to pass a command line argument through panel serve to my script (i.e. --c my_config.yml). If I add an --args before that, it would pass a --index to my script (!?).

1 Like
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Hi @nritsche

Welcome to the community.

Great question.

You can actually use panel.serve. See the section Serving multiple apps at https://panel.holoviz.org/user_guide/Deploy_and_Export.html

Please note that Setting num_procs does not Work. I would really like it to as this is important when you start to have more users as i do at awesome-panel.org.

Please upvote the issue https://github.com/holoviz/panel/issues/1405 if this is important for you as well.

2 Likes
3

Thanks @Marc!

panel.serve(my_template) works, but it produces the same results as template.show() (also if I pass show=False to it):
It starts a server, but if I connect to it with two different browsers and interact with the plot in one browser, it also affects the plot in the other browser. I couldn’t find an option to change that. I think what is needed is that it starts an instance of panel for every user that connects to it.

The command line panel serve myscript.py does that, I think. At least I managed to do that yesterday. Now it exits after I connect to it once and I don’t remember what the solution to that was.

4

If you pass a Panel object to pn.serve it will indeed be shared between all sessions and this is to be expected. However you can pass a function to pn.serve which will then be called and return a new object for each session.

2 Likes
5

That makes sense. Thanks!

edit:
I want to add here, that

server = MyServer()
def instance():
    return server.gui_instance()
panel.serve(instance)

works, but not

server = MyServer()
panel.serve(server.gui_instance)
6

Thanks for that, would you mind filing an issue and/or PR? Looks like it’s only checking for FunctionType:

if isinstance(panel, FunctionType):
    panel = panel()
7

Sure, I’ll have a look on Monday :slight_smile: