Declare the weekly upgrade timer with its health, and serve pacman_upgrade_health (issue 1574, ADR 0477)

modules/pacman/cmd/pacman-tools/acts.go

@@ -55,6 +55,11 @@ func (m *Machine) journal(unit string, n int) []string {
 	return lines(out)
 }
 
+// UpgradeArgs is the full system upgrade, in one place: pacman_upgrade starts pacman with these arguments as
+// a transient unit, and the weekly upgrade's service (files/mesh-pacman-weekly-upgrade.service) runs
+// pacman with the same ones; a test holds the two together (issue 1574, ADR 0477 clause 5).
+var UpgradeArgs = []string{"-Syu", "--noconfirm"}
+
 // Upgrade starts a full system upgrade as a transient unit and answers at once, with the
 // distribution's news since the last upgrade; or, given a unit it started, answers how it went.
 func (m *Machine) Upgrade(unit string, n int) (map[string]any, error) {
@@ -62,7 +67,7 @@ func (m *Machine) Upgrade(unit string, n int) (map[string]any, error) {
 		return m.UpgradeStatus(unit, n)
 	}
 	news := m.News("")
-	started, _, err := m.transaction("upgrade", false, "-Syu", "--noconfirm")
+	started, _, err := m.transaction("upgrade", false, UpgradeArgs...)
 	if err != nil {
 		return nil, err
 	}

modules/pacman/cmd/pacman-tools/main.go

@@ -152,6 +152,13 @@ func tools(m *Machine) []stdio.Tool {
 				return m.Upgrade(unit, n)
 			},
 		},
+		{
+			Name: "pacman_upgrade_health",
+			Description: "Whether the weekly full upgrade (Saturday 04:00 local time, ADR 0477) last passed, as the module's health check: unhealthy " +
+				"with the exit and the last error of the journal when it failed, healthy while it runs, after it passed and before it ever ran. (r)",
+			Input: schema(map[string]any{}),
+			Run:   func(map[string]any) (any, error) { return m.UpgradeHealth(), nil },
+		},
 		{
 			Name:        "pacman_orphans",
 			Description: "Packages installed as dependencies that nothing requires any more (pacman -Qdt), with versions.",

modules/pacman/module.json

@@ -19,6 +19,7 @@
     "pacman_files",
     "pacman_updates",
     "pacman_upgrade",
+    "pacman_upgrade_health",
     "pacman_orphans",
     "pacman_remove_orphans",
     "pacman_cache",
@@ -63,14 +64,53 @@
       "type": "service",
       "unit": "reflector.timer",
       "state": "running",
-      "boot": "enabled"
+      "boot": "enabled",
+      "health": {
+        "kind": "unit"
+      }
     },
     {
       "id": "cache-cleaning",
       "type": "service",
       "unit": "paccache.timer",
       "state": "running",
-      "boot": "enabled"
+      "boot": "enabled",
+      "health": {
+        "kind": "unit"
+      }
+    },
+    {
+      "id": "upgrade-service",
+      "type": "file",
+      "path": "/etc/systemd/system/mesh-pacman-weekly-upgrade.service",
+      "mode": "0644",
+      "template": "files/mesh-pacman-weekly-upgrade.service"
+    },
+    {
+      "id": "upgrade-timer",
+      "type": "file",
+      "path": "/etc/systemd/system/mesh-pacman-weekly-upgrade.timer",
+      "mode": "0644",
+      "template": "files/mesh-pacman-weekly-upgrade.timer"
+    },
+    {
+      "id": "weekly-upgrade",
+      "type": "service",
+      "unit": "mesh-pacman-weekly-upgrade.timer",
+      "state": "running",
+      "boot": "enabled",
+      "restart-on": [
+        "upgrade-service",
+        "upgrade-timer"
+      ],
+      "health": {
+        "kind": "tool",
+        "tool": "pacman_upgrade_health",
+        "interval": "60s",
+        "timeout": "20s",
+        "looks": 2,
+        "grace": "60s"
+      }
     }
   ],
   "build": {