feat: Diagnostics panel

[matmen]

Adds a new opt-in diagnostics panel with customizable metrics logging.

Closes #454

[matmen]

I have this working to a point where data is automatically collected and charts will dynamically be rendered.
The only thing missing now is a proper, working layout for the configuration modals, but I'm not sure what the best way would be to implement those.
Not sure if the current data structure is the most optimal yet or if there's other info missing (for example for dynamic computation based on properties? e.g. converting live_extruder_velocity to flow? This would be much more complex, I'm not sure how to implement this UI wise and also code wise. Suggestions welcome 😉)

[matmen]

Adding the ability to script metrics would be very handy (think

Math.PI * (printer.printer.extruder.filament_diameter / 2) ** 2 * printer.printer.motion_report.live_extruder_velocity

to calculate volumetric flow), but this would require some sort of sandbox or custom parsing..

The alternative would be creating a fixed list of loggable metrics, but this kinda locks this feature down a lot.

[pedrolamas]

Adding the ability to script metrics would be very handy

That would be really neat!! I guess the "hammer" approach would be to use eval and that is something we DO NOT want to do!

[matmen]

I guess the "hammer" approach would be to use eval and that is something we DO NOT want to do!

Correct. I guess the best approach here would be injecting a sandboxed iframe which would then evaluate the code in an isolated context. Should be fairly easy to implement tbh, I'll work on that later.

[pedrolamas]

Really, REALLY love this new feature!! I think this will make a lot of users very happy!!

I'm not sure of these buttons:

Either change to round ones, or instead of icons just add text to them (either way matching what we do on the other dialogs)

"Add Card" is correct, but I think "Add Chart" would make more sense (these are all charts, correct?)

[pedrolamas]

Not sure of the impact of enabling diagnostics, but should we add a footer here with a warning?

[matmen]

Not sure of the impact of enabling diagnostics, but should we add a footer here with a warning?

The impact isn't negligible (about a 5.7% decrease in idle time from what I've measured).
What do you think the wording here should be, Logging diagnostics info may impact performance?

[matmen]

I did notice that during printing, the 250ms update rate makes the configuration dialog pretty much unusable (with the charts being re-rendered every time).

Edit: Also looks like the entire UI becomes unresponsive after a couple minutes, will definitely need to check that out...

[pedrolamas]

What do you think the wording here should be, Logging diagnostics info may impact performance?

Works for me! 🙂

[matmen]

I've optimized the metrics collection a bit further (from ~20ms to ~5ms):

I'm still unsure why the client starts freezing after a while, from performance monitoring it looks like everything just gets slower (proportionally the same), even things unrelated to this feature. I assume it has something to do with the state being polluted, but I'm not 100% sure.

[matmen]

Well, looks like it indeed is "polluting" the state, I didn't think storing the metrics in the state would make this much difference.. Basically, with a retention of 10 minutes, there's up to 3000 data points in the state during printing (compared to 600 max per other chart). Not sure how to solve this..

[matmen]

I've stumbled across this thread on the Vue forum which describes a similar problem, and it looks like the performance issues aren't there in the production build (we disable strict mode in production builds).
Not sure what the implications of disabling strict mode are in the dev build, so I would just leave it enabled and cope with the performance loss there.
Below are the two CPU load graphs, upper one is the production build, lower one the dev build.

[pedrolamas]

I will try to take a look into this too (later today if I manage, or tomorrow), but I'm starting to wonder if this shouldn't actually be done on Moonraker (offload to the server)