From f1e7c5da5f13c4d229bc86f63d4b1bc47353f8b8 Mon Sep 17 00:00:00 2001
From: Eliza Weisman <eliza@elizas.website>
Date: Mon, 1 Jul 2024 13:03:33 -0700
Subject: [PATCH] add instance-updater omdb stuff

---
 dev-tools/omdb/src/bin/omdb/nexus.rs | 46 ++++++++++++++++++++++++++++
 dev-tools/omdb/tests/successes.out   |  7 +++--
 2 files changed, 51 insertions(+), 2 deletions(-)

diff --git a/dev-tools/omdb/src/bin/omdb/nexus.rs b/dev-tools/omdb/src/bin/omdb/nexus.rs
index fe13ca797bc..aa3b7151f7f 100644
--- a/dev-tools/omdb/src/bin/omdb/nexus.rs
+++ b/dev-tools/omdb/src/bin/omdb/nexus.rs
@@ -1086,6 +1086,52 @@ fn print_task_details(bgtask: &BackgroundTask, details: &serde_json::Value) {
                 }
             }
         };
+    } else if name == "instance_updater" {
+        #[derive(Deserialize)]
+        struct UpdaterStatus {
+            /// number of instances found with destroyed active VMMs
+            destroyed_active_vmms: usize,
+
+            /// number of instances found with terminated active migrations
+            terminated_active_migrations: usize,
+
+            /// number of update sagas queued.
+            update_sagas_queued: usize,
+
+            /// the last error that occurred during execution.
+            error: Option<String>,
+        }
+        match serde_json::from_value::<UpdaterStatus>(details.clone()) {
+            Err(error) => eprintln!(
+                "warning: failed to interpret task details: {:?}: {:?}",
+                error, details
+            ),
+            Ok(UpdaterStatus {
+                destroyed_active_vmms,
+                terminated_active_migrations,
+                update_sagas_queued,
+                error,
+            }) => {
+                if let Some(error) = error {
+                    println!("    task did not complete successfully!");
+                    println!("      most recent error: {error}");
+                }
+
+                println!(
+                    "    total instances in need of updates: {}",
+                    destroyed_active_vmms + terminated_active_migrations
+                );
+                println!(
+                    "      instances with destroyed active VMMs: {}",
+                    destroyed_active_vmms,
+                );
+                println!(
+                    "      instances with terminated active migrations: {}",
+                    terminated_active_migrations,
+                );
+                println!("    update sagas queued: {update_sagas_queued}");
+            }
+        };
     } else {
         println!(
             "warning: unknown background task: {:?} \
diff --git a/dev-tools/omdb/tests/successes.out b/dev-tools/omdb/tests/successes.out
index 8018dfe66f2..7c239ae0074 100644
--- a/dev-tools/omdb/tests/successes.out
+++ b/dev-tools/omdb/tests/successes.out
@@ -469,9 +469,12 @@ task: "external_endpoints"
 task: "instance_updater"
   configured period: every 30s
   currently executing: no
-  last completed activation: <REDACTED ITERATIONS>, triggered by an explicit signal
+  last completed activation: <REDACTED ITERATIONS>, triggered by a periodic timer firing
     started at <REDACTED     TIMESTAMP> (<REDACTED DURATION>s ago) and ran for <REDACTED DURATION>ms
-warning: unknown background task: "instance_updater" (don't know how to interpret details: Object {"destroyed_active_vmms": Number(0), "error": Null, "sagas_started": Number(0)})
+    total instances in need of updates: 0
+      instances with destroyed active VMMs: 0
+      instances with terminated active migrations: 0
+    update sagas queued: 0
 
 task: "instance_watcher"
   configured period: every 30s