Machine-readable variant of the `start` progress output

[afbjorklund]

Description

After adding the human-readable variant of the progress in #1311, a machine-readable variant is also useful.

The plan was to use it for the GUI, to show a progress dialog instead of just spinning the cursor (like today)

https://doc.qt.io/qt-5/qprogressdialog.html#details

Human readable:

Starting "default"
Waiting 1 / 8 [--->________________________]  "ssh" (essential 1/5)                                 
Waiting 2 / 8 [------>_____________________]  "user session is ready for ssh" (essential 2/5)       
Waiting 3 / 8 [---------->_________________]  "sshfs binary to be installed" (essential 3/5)        
Waiting 4 / 8 [------------->______________]  "fuse to \"allow_other\" as user" (essential 4/5)     
Waiting 5 / 8 [----------------->__________]  "the guest agent to be running" (essential 5/5)       
Waiting 6 / 8 [-------------------->_______]  "systemd must be available" (optional 1/2)            
Waiting 7 / 8 [------------------------>___]  "containerd binaries to be installed" (optional 2/2)  
Waiting 8 / 8 [----------------------------]  "boot scripts must have finished" (final 1/1)         
READY.

Machine readable:

{"name":"default","progress":"Booting"}
{"name":"default","requirement":{"label":"essential","number":1,"count":5,"description":"ssh","index":0,"total":8}}
{"name":"default","requirement":{"label":"essential","number":2,"count":5,"description":"user session is ready for ssh","index":1,"total":8}}
{"name":"default","requirement":{"label":"essential","number":3,"count":5,"description":"sshfs binary to be installed","index":2,"total":8}}
{"name":"default","requirement":{"label":"essential","number":4,"count":5,"description":"fuse to \"allow_other\" as user","index":3,"total":8}}
{"name":"default","requirement":{"label":"essential","number":5,"count":5,"description":"the guest agent to be running","index":4,"total":8}}
{"name":"default","requirement":{"label":"optional","number":1,"count":2,"description":"systemd must be available","index":5,"total":8}}
{"name":"default","requirement":{"label":"optional","number":2,"count":2,"description":"containerd binaries to be installed","index":6,"total":8}}
{"name":"default","requirement":{"label":"final","number":1,"count":1,"description":"boot scripts must have finished","index":7,"total":8}}
{"name":"default","progress":"Running"}

It would also affect the download output...

It needs a special pb template, for JSON lines.

And also a JSON wrapper, for the message.

[afbjorklund]

https://github.com/containerd/nerdctl/releases/download/v1.1.0/nerdctl-full-1.1.0-linux-amd64.tar.gz
3.48 MiB / 224.27 MiB [>______________________________________] 1.55% 2.00 MiB/s^C

                bar.SetTemplateString(`{{counters . }} {{bar . | green }} {{percent .}} {{speed . "%s/s"}}`)

Something like this:

{"current":19431424,"total":235161071,"percent":"8.26%","speed":"? p/s","url":"https://github.com/containerd/nerdctl/releases/download/v1.1.0/nerdctl-full-1.1.0-linux-amd64.tar.gz"}
{"current":24985600,"total":235161071,"percent":"10.62%","speed":"5.32 MiB/s","url":"https://github.com/containerd/nerdctl/releases/download/v1.1.0/nerdctl-full-1.1.0-linux-amd64.tar.gz"}
{"current":28213248,"total":235161071,"percent":"12.00%","speed":"5.17 MiB/s","url":"https://github.com/containerd/nerdctl/releases/download/v1.1.0/nerdctl-full-1.1.0-linux-amd64.tar.gz"}
^C

               bar.Set("url", url)
               pb.RegisterElement("int", elementInt, false)
               bar.Set(pb.ReturnSymbol, "")
               bar.SetTemplateString(`{"current":{{int . "current"}},"total":{{int . "total"}},` +
                       `"percent":"{{percent .}}","speed":"{{speed . "%s/s"}}",` +
                       `"url":"{{string . "url"}}"}` + "\n")

[AkihiroSuda]

I guess we should have --progress-json=JSONFILE, then we can have human-friendly output and machine-friendly output simultaneously.

[afbjorklund]

The example code is here:

afbjorklund/lima@progress...afbjorklund:lima:progress-json

It was just a test, on top of:

• Add progress option for showing progress only #1312

---

It can be adopted to Fprint, it was just that currently I am reading stdout to get the message for the user.

https://github.com/afbjorklund/lima-gui/blob/v0.2.2/window.cpp#L737_L744

But it would have to be changed anyway, to read streaming output rather than just everything at once.

https://doc.qt.io/qt-6/qprocess.html#details