Read only disks

[david-crespo]

Threw this together real quick to de-risk and get a sense of the vibes. API built from oxidecomputer/omicron#9731, which isn't merged yet and we're not sure if it will make it in for v18. This is built on top of #3005 because that has earlier API changes in it.

Fun questions

• I put the read-only badge right in the name cell because it would be excessive to give it its own column, but really it doesn't feel great there either. Maybe if we had a read-only icon that you could hover on to get a label, it would work better in the name cell.
• Read only: Yes in the side modal looks silly, also not as grouped together with snapshot ID as I would like.
• Copy for the checkbox label (and possibly help text) — "Make disk read-only" is weird, as Ben points out

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[benjaminleonard]

Such a silly nit, but I feel like even if it's made uppercase its good practice to case them properly

[benjaminleonard]

"Make disk" is strange? Maybe just "Read-only"

[david-crespo]

I put that in there tentatively because when it was just read-only, it wasn't clear enough that read-only refers to the resulting disk. So I think we need something more than read-only. Unless we just make the label "Read only" and we put help text in there that says "Instances won't be able to write to this disk" or something. I am also slightly torn about the hyphen. Generally I feel like hyphen is right for regular copy, but when it's just "Read-only" by itself it looks bad.

[benjaminleonard]

Are there consequences to this action we want to communicate after the user has checked the box? Do we need to clarify that it cannot edited later?

[benjaminleonard]

Scattergun thoughts contd:

1. Can you use it for boot disks, or just additional ones?
   1a. If you can, how does cloud init work?
2. Will it always just be for snapshots? Or images too?

[david-crespo]

1. Yes, can boot — sounds like this is the main use case
   a. Great question. @hawkw is checking. Edit: the cloud init volume is its own PCI device and should not be affected by the boot disk being read only.
2. Images coming in like one hour lol

[david-crespo]

Further update on cloud-init: because cloud-init is fundamentally a program that runs in the guest OS and pulls data from the CIDATA volume, they just have to not do that (chat).

[hawkw]

@benjaminleonard:

Are there consequences to this action we want to communicate after the user has checked the box? Do we need to clarify that it cannot edited later?

I'd like to add some stuff to the docs about read-only disks, perhaps the checkbox should have a link to there?

@david-crespo:

2. Images coming in like one hour lol

As of oxidecomputer/omicron@4c3bd6b, it should also be an option for DiskSource::Image (slightly less than an hour lol). :)