1 files changed, 95 insertions, 0 deletions
diff --git a/controller-server/src/main/java/com/yahoo/vespa/hosted/controller/maintenance/OsUpgradeScheduler.java b/controller-server/src/main/java/com/yahoo/vespa/hosted/controller/maintenance/OsUpgradeScheduler.java
new file mode 100644
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+++ b/controller-server/src/main/java/com/yahoo/vespa/hosted/controller/maintenance/OsUpgradeScheduler.java
@@ -0,0 +1,95 @@
+// Copyright Verizon Media. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.hosted.controller.maintenance;
+
+import com.yahoo.component.Version;
+import com.yahoo.config.provision.CloudName;
+import com.yahoo.config.provision.zone.ZoneApi;
+import com.yahoo.vespa.hosted.controller.Controller;
+import com.yahoo.vespa.hosted.controller.versions.OsVersion;
+import com.yahoo.vespa.hosted.controller.versions.OsVersionTarget;
+
+import java.time.Duration;
+import java.time.Instant;
+import java.time.LocalDate;
+import java.time.ZoneOffset;
+import java.time.format.DateTimeFormatter;
+import java.util.Optional;
+import java.util.Set;
+import java.util.stream.Collectors;
+
+/**
+ * Automatically schedule OS upgrades.
+ *
+ * This is used in clouds where new OS versions regularly become available.
+ *
+ * @author mpolden
+ */
+public class OsUpgradeScheduler extends ControllerMaintainer {
+
+    /** Trigger a new upgrade when the current target version reaches this age */
+    private static final Duration MAX_VERSION_AGE = Duration.ofDays(30);
+
+    /**
+     * The interval at which new versions become available. We use this to avoid scheduling upgrades to a version that
+     * may not be available yet
+     */
+    private static final Duration AVAILABILITY_INTERVAL = Duration.ofDays(7);
+
+    private static final DateTimeFormatter VERSION_DATE_PATTERN = DateTimeFormatter.ofPattern("yyyyMMdd");
+
+    public OsUpgradeScheduler(Controller controller, Duration interval) {
+        super(controller, interval);
+    }
+
+    @Override
+    protected boolean maintain() {
+        for (var cloud : supportedClouds()) {
+            Optional<Version> newTarget = newTargetIn(cloud);
+            if (newTarget.isEmpty()) continue;
+            controller().upgradeOsIn(cloud, newTarget.get(), Optional.of(upgradeBudget()), false);
+        }
+        return true;
+    }
+
+    /** Returns the new target version for given cloud, if any */
+    private Optional<Version> newTargetIn(CloudName cloud) {
+        Optional<Version> currentTarget = controller().osVersionTarget(cloud)
+                                                      .map(OsVersionTarget::osVersion)
+                                                      .map(OsVersion::version);
+        if (currentTarget.isEmpty()) return Optional.empty();
+        if (!hasExpired(currentTarget.get())) return Optional.empty();
+
+        Instant now = controller().clock().instant();
+        String qualifier = LocalDate.ofInstant(now.minus(AVAILABILITY_INTERVAL), ZoneOffset.UTC)
+                                    .format(VERSION_DATE_PATTERN);
+        return Optional.of(new Version(currentTarget.get().getMajor(),
+                                       currentTarget.get().getMinor(),
+                                       currentTarget.get().getMicro(),
+                                       qualifier));
+    }
+
+    /** Returns whether we should upgrade from given version */
+    private boolean hasExpired(Version version) {
+        String qualifier = version.getQualifier();
+        if (!qualifier.matches("^\\d{8,}")) return false;
+
+        String dateString = qualifier.substring(0, 8);
+        Instant now = controller().clock().instant();
+        Instant versionDate = LocalDate.parse(dateString, VERSION_DATE_PATTERN)
+                                       .atStartOfDay(ZoneOffset.UTC)
+                                       .toInstant();
+        return versionDate.isBefore(now.minus(MAX_VERSION_AGE));
+    }
+
+    /** Returns the clouds where we can safely schedule OS upgrades */
+    private Set<CloudName> supportedClouds() {
+        return controller().zoneRegistry().zones().reprovisionToUpgradeOs().zones().stream()
+                           .map(ZoneApi::getCloudName)
+                           .collect(Collectors.toUnmodifiableSet());
+    }
+
+    private Duration upgradeBudget() {
+        return controller().system().isCd() ? Duration.ofHours(1) : Duration.ofDays(14);
+    }
+
+}