Operator View: Updates - what version am I on?

[smklein]

The operator API should be API to report the version of a variety of subcomponents on the rack. Note that this should be as "honest as possible", describing different subcomponents which may even change across a more broad update.

Also note: This API should probably not be a traditional CRUD API -- we do want the ability to read, but we don't want unrestricted ability to update subcomponents to arbitrary versions.

[smklein]

Assigning this to @david-crespo who mentioned working on the API skeleton. I'm happy to help out with chunks of the backend; feel free to loop me in wherever you need help.

[smklein]

See also: #2105

[david-crespo]

Can we call this complete?

omicron/nexus/src/external_api/http_entrypoints.rs

Lines 5425 to 5460 in de62418

	/// View system version and update status
	#[endpoint {
	method = GET,
	path = "/v1/system/update/version",
	tags = ["system"],
	}]
	async fn system_version(
	rqctx: RequestContext<Arc<ServerContext>>,
	) -> Result<HttpResponseOk<views::SystemVersion>, HttpError> {
	let apictx = rqctx.context();
	let nexus = &apictx.nexus;
	let handler = async {
	let opctx = OpContext::for_external_api(&rqctx).await?;
	opctx.authorize(authz::Action::ListChildren, &authz::FLEET).await?;
	// The only way we have no latest deployment is if the rack was just set
	// up and no system updates have ever been run. In this case there is no
	// update running, so we can fall back to steady.
	let status = nexus
	.latest_update_deployment(&opctx)
	.await
	.map_or(views::UpdateStatus::Steady, |d| d.status.into());
	// Updateable components, however, are populated at rack setup before
	// the external API is even started, so if we get here and there are no
	// components, that's a real issue and the 500 we throw is appropriate.
	let low = nexus.lowest_component_system_version(&opctx).await?.into();
	let high = nexus.highest_component_system_version(&opctx).await?.into();
	Ok(HttpResponseOk(views::SystemVersion {
	version_range: views::VersionRange { low, high },
	status,
	}))
	};
	apictx.external_latencies.instrument_dropshot_handler(&rqctx, handler).await
	}

[david-crespo]

Closed by #2100