capturing console output

[wjh-97]

Hey guys! I would greatly appreciate a simple example of how to utilize the "begin_capture_print" function to catch stdout/stderr. My plan is to send console output to a RichLog widget but can't get it to work.

[davep]

Often, if you can't get something to work, it can be a good idea to show what you tried and say how it failed so we can help correct any misunderstanding.

To start with, here's an example of an application that logs the time every second, capturing a print to do it:

from datetime import datetime

from textual.app import App, ComposeResult
from textual.events import Print
from textual.widgets import Log

class PrintLog(Log):

    def on_mount(self) -> None:
        self.begin_capture_print()

    def on_print(self, event: Print) -> None:
        self.write(event.text)

class PrintLogApp(App[None]):

    def compose(self) -> ComposeResult:
        yield PrintLog()

    def print_time(self) -> None:
        print(str(datetime.now()))

    def on_mount(self) -> None:
        self.set_interval(1.0, self.print_time)

if __name__ == "__main__":
    PrintLogApp().run()

[wjh-97]

The "on_print" function is what I was missing. Thanks Dave!

[davep]

Glad to help. To tie it together: in the documentation for begin_capture_print you'll notice it says:

If printing is captured, the widget will be sent an events.Print message.

So what I added there is an event handler for the Print message.