App logs window scroll issues

[robi]

If the logs contain long log lines and one moves the browser window to see them, each new log line reset the view, which isn't helpful.

Please refresh logs without resetting page position horizontal scroll.

[nebulon]

I agree this is no ideal, so once you vertically scroll a bit, the position should not be reset anymore. I haven't figured how to only scroll horizontally while following logs.

[robi]

@nebulon Since new log lines inject and start from left to right, that seems to reset the view as it follows the cursor focus at least initially?

There are other log windows where this doesn't occur. How are they different?

Another thought is that perhaps by adding a transparent layer on top of the logs, it will allow the window to remain static but have logs keep coming.

An improvement idea would be to have the log windows function more like less -F which can be cancelled and then searched via / and other useful less commands.

[rmdes]

I use Byobu F7 key to freeze the terminal log move up (pgup) and down (pgdown) in the log, works really great, you then ESC to escape the freeze and back to last log line, works nicely

[robi]

@rmdes nice, and I use ctrl-a+[ in screen to do the same, but that doesn't apply here talking about logs from the Cloudron GUI

[rmdes]

@robi Whoops indeed, I was lost in between terminals :))

[robi]

This is still an issue.

Would it help if the log lines were printed from right to left?

How do we maintain the browser viewport on the relevant part of the log as new lines come in?

[girish]

In firefox, when I scroll up, the view does not automatically scroll for me when as new lines come in.

[robi]

@girish Up is not the issue, to the right is.. scroll right on long log lines, then see the window snap back to the left.

[girish]

Horizontal scroll seems fine too.

Download video

[robi]

It's not an issue if scrolled up already, but at the bottom and to the right.

[girish]

@robi Ah I see. If it's fully vertically scrolled, it auto scrolls. If you scroll up even a tiny bit, it will stop auto scrolling. I think this behavior is copied from gnome-terminal and the like. How does your terminal do it?

[robi]

That's the subtle bit.. without resetting back to the left.

Often monitoring progress of something which is off screen to the right, scrolling over it should keep that window frame and allow for new lines without changing window view to the left.

[girish]

I think the behavior even comes from upstream xterm.js but @nebulon can confirm

[nebulon]

The logviewer does not use xterm.js but just plain DOM elements. The root cause of this is, that we call scrollIntoView() for an anchor element at the bottom of the page, if the user has not vertically scrolled.
Since this element sits bottom left, the browser also scrolls left. I will see what can be done to keep horizontal scroll position.

[nebulon]

This is fixed with https://git.cloudron.io/cloudron/box/-/commit/fe1c483b7819404d4531fd34323bc2fc18534b85 now