Make UnstableReconfiguratorState::target_blueprint non-optional

dev-tools/omdb/src/bin/omdb/reconfigurator.rs

@@ -202,14 +202,7 @@ async fn cmd_reconfigurator_archive(
     //    successfully archived some blueprints before hitting this error. We
     //    attempt to notice this and log a message for the operator in this
     //    case.
-    let target_blueprint_id = saved_state
-        .target_blueprint
-        .context(
-            "system has no current target blueprint: \
-             cannot remove non-target blueprints",
-        )?
-        .target_id;
-
+    let target_blueprint_id = saved_state.target_blueprint.target_id;
     let mut ndeleted = 0;
 
     eprintln!("removing saved, non-target blueprints ...");

dev-tools/reconfigurator-cli/src/lib.rs

@@ -2099,12 +2099,12 @@ fn cmd_blueprint_list(
     let mut rows = state.system().all_blueprints().collect::<Vec<_>>();
     rows.sort_unstable_by_key(|blueprint| blueprint.time_created);
     let rows = rows.into_iter().map(|blueprint| {
-        let (is_target, enabled) = match target_blueprint {
-            Some(t) if t.target_id == blueprint.id => {
-                let enabled = if t.enabled { "yes" } else { "no" };
-                ("*", enabled)
-            }
-            _ => ("", ""),
+        let (is_target, enabled) = if target_blueprint.target_id == blueprint.id
+        {
+            let enabled = if target_blueprint.enabled { "yes" } else { "no" };
+            ("*", enabled)
+        } else {
+            ("", "")
         };
         BlueprintRow {
             is_target,

dev-tools/reconfigurator-cli/tests/output/cmds-stdout

@@ -11,7 +11,8 @@ ID SERIAL NZPOOLS SUBNET
 ID NERRORS TIME_DONE 
 
 > blueprint-list
-T ENA ID PARENT TIME_CREATED 
+T ENA ID                                   PARENT TIME_CREATED             
+* no  00000000-0000-0000-0000-000000000000 <none> <REDACTED_TIMESTAMP> 
 
 
 > sled-show dde1c0e2-b10d-4621-b420-f179f7a7a00a
@@ -863,14 +864,12 @@ wiped system
 
 > load state.json
 loaded data from "state.json"
-warnings:
-  could not determine active Nexus generation from serialized state: no target blueprint set (using default of 1)
 result:
   system:
     using collection 6e066695-94bc-4250-bd63-fd799c166cc1 as source of sled inventory data
     loaded sleds: 04ef3330-c682-4a08-8def-fcc4bef31bcd, 90c1102a-b9f5-4d88-92a2-60d54a2d98cc, dde1c0e2-b10d-4621-b420-f179f7a7a00a
     loaded collections: 6e066695-94bc-4250-bd63-fd799c166cc1
-    loaded blueprints: (none)
+    loaded blueprints: 00000000-0000-0000-0000-000000000000
     loaded external IP policy: ExternalIpPolicy { service_pool_ipv4_ranges: [Ipv4Range { first: 192.0.2.2, last: 192.0.2.20 }], service_pool_ipv6_ranges: [], external_dns_ips: {} }
     loaded internal DNS generations: (none)
     loaded external DNS generations: (none)

nexus/reconfigurator/preparation/src/lib.rs

@@ -582,7 +582,7 @@ pub async fn reconfigurator_state_load(
     Ok(UnstableReconfiguratorState {
         planning_input,
         collections,
-        target_blueprint: Some(target_blueprint),
+        target_blueprint,
         blueprints,
         internal_dns,
         external_dns,

nexus/reconfigurator/simulation/src/config.rs

@@ -166,7 +166,7 @@ impl SimConfigBuilder {
         external_dns_zone_names: Vec<String>,
         silo_names: Vec<Name>,
         active_nexus_zones: &BTreeSet<OmicronZoneUuid>,
-        target_blueprint: Option<&BlueprintTarget>,
+        target_blueprint: &BlueprintTarget,
         all_blueprints: &[Blueprint],
         res: &mut LoadSerializedResultBuilder,
     ) -> LoadSerializedConfigResult {
@@ -301,7 +301,7 @@ impl SimConfigBuilderInner {
         external_dns_zone_names: Vec<String>,
         silo_names: Vec<Name>,
         active_nexus_zones: &BTreeSet<OmicronZoneUuid>,
-        target_blueprint: Option<&BlueprintTarget>,
+        target_blueprint: &BlueprintTarget,
         all_blueprints: &[Blueprint],
         res: &mut LoadSerializedResultBuilder,
     ) -> LoadSerializedConfigResult {
@@ -403,12 +403,17 @@ impl SimConfigBuilderInner {
 
 fn determine_active_nexus_generation(
     active_nexus_zones: &BTreeSet<OmicronZoneUuid>,
-    target_blueprint: Option<&BlueprintTarget>,
+    target_blueprint: &BlueprintTarget,
     all_blueprints: &[Blueprint],
 ) -> Result<Generation, String> {
-    let Some(target_blueprint) = target_blueprint else {
-        return Err("no target blueprint set".to_string());
-    };
+    // Real systems always have at least one active Nexus zone, but our
+    // simulated system has some cases where we have none at all. We'll never be
+    // able to find the generation matching an empty set, but because this is a
+    // weird edge case that only applies to simulation, it's also fine to
+    // default to "the initial generation".
+    if active_nexus_zones.is_empty() {
+        return Ok(Generation::new());
+    }
 
     let Some(blueprint) =
         all_blueprints.iter().find(|bp| bp.id == target_blueprint.target_id)

nexus/reconfigurator/simulation/src/errors.rs

@@ -105,10 +105,6 @@ impl KeyError {
         Self { id: ObjectId::Collection(id) }
     }
 
-    pub(crate) fn blueprint(id: BlueprintId) -> Self {
-        Self { id: ObjectId::Blueprint(id) }
-    }
-
     pub(crate) fn resolved_collection(id: ResolvedCollectionId) -> Self {
         Self { id: ObjectId::ResolvedCollection(id) }
     }

nexus/reconfigurator/simulation/src/state.rs

@@ -237,7 +237,7 @@ impl SimStateBuilder {
             state.external_dns_zone_names.clone(),
             state.silo_names.clone(),
             state.planning_input.active_nexus_zones(),
-            state.target_blueprint.as_ref(),
+            &state.target_blueprint,
             &state.blueprints,
             &mut res,
         );