1 files changed, 36 insertions, 15 deletions

diff --git a/controller-server/src/main/java/com/yahoo/vespa/hosted/controller/maintenance/InfrastructureUpgrader.java b/controller-server/src/main/java/com/yahoo/vespa/hosted/controller/maintenance/InfrastructureUpgrader.java
index bb10410d2ef..82413f21222 100644
--- a/controller-server/src/main/java/com/yahoo/vespa/hosted/controller/maintenance/InfrastructureUpgrader.java
+++ b/controller-server/src/main/java/com/yahoo/vespa/hosted/controller/maintenance/InfrastructureUpgrader.java
@@ -10,14 +10,19 @@ import com.yahoo.vespa.hosted.controller.Controller;
 import com.yahoo.vespa.hosted.controller.api.integration.configserver.Node;
 import com.yahoo.vespa.hosted.controller.api.integration.configserver.NodeFilter;
 import com.yahoo.vespa.hosted.controller.application.SystemApplication;
+import com.yahoo.vespa.hosted.controller.versions.VersionTarget;
 import com.yahoo.yolean.Exceptions;
 
 import java.time.Duration;
 import java.util.Comparator;
 import java.util.EnumSet;
+import java.util.HashMap;
+import java.util.HashSet;
 import java.util.List;
+import java.util.Map;
 import java.util.Objects;
 import java.util.Optional;
+import java.util.Set;
 import java.util.function.Function;
 import java.util.logging.Logger;
 
@@ -26,7 +31,7 @@ import java.util.logging.Logger;
  *
  * @author mpolden
  */
-public abstract class InfrastructureUpgrader<VERSION> extends ControllerMaintainer {
+public abstract class InfrastructureUpgrader<TARGET extends VersionTarget> extends ControllerMaintainer {
 
     private static final Logger log = Logger.getLogger(InfrastructureUpgrader.class.getName());
 
@@ -42,17 +47,19 @@ public abstract class InfrastructureUpgrader<VERSION> extends ControllerMaintain
 
     @Override
     protected double maintain() {
-        if (targetVersion().isEmpty())  return 1.0;
-        return upgradeAll(targetVersion().get(), managedApplications);
+        return target().map(target -> upgradeAll(target, managedApplications))
+                       .orElse(1.0);
     }
 
     /** Deploy a list of system applications until they converge on the given version */
-    private double upgradeAll(VERSION target, List<SystemApplication> applications) {
+    private double upgradeAll(TARGET target, List<SystemApplication> applications) {
         int attempts = 0;
         int failures = 0;
-        for (List<ZoneApi> zones : upgradePolicy.asList()) {
+        // Invert zone order if we're downgrading
+        UpgradePolicy policy = target.downgrade() ? upgradePolicy.inverted() : upgradePolicy;
+        for (Set<ZoneApi> step : policy.steps()) {
             boolean converged = true;
-            for (ZoneApi zone : zones) {
+            for (ZoneApi zone : step) {
                 try {
                     attempts++;
                     converged &= upgradeAll(target, applications, zone);
@@ -76,10 +83,24 @@ public abstract class InfrastructureUpgrader<VERSION> extends ControllerMaintain
     }
 
     /** Returns whether all applications have converged to the target version in zone */
-    private boolean upgradeAll(VERSION target, List<SystemApplication> applications, ZoneApi zone) {
+    private boolean upgradeAll(TARGET target, List<SystemApplication> applications, ZoneApi zone) {
+        Map<SystemApplication, Set<SystemApplication>> dependenciesByApplication = new HashMap<>();
+        if (target.downgrade()) { // Invert dependencies when we're downgrading
+            for (var application : applications) {
+                dependenciesByApplication.computeIfAbsent(application, k -> new HashSet<>());
+                for (var dependency : application.dependencies()) {
+                    dependenciesByApplication.computeIfAbsent(dependency, k -> new HashSet<>())
+                                             .add(application);
+                }
+            }
+        } else {
+            applications.forEach(app -> dependenciesByApplication.put(app, Set.copyOf(app.dependencies())));
+        }
         boolean converged = true;
-        for (SystemApplication application : applications) {
-            if (convergedOn(target, application.dependencies(), zone)) {
+        for (var kv : dependenciesByApplication.entrySet()) {
+            SystemApplication application = kv.getKey();
+            Set<SystemApplication> dependencies = kv.getValue();
+            if (convergedOn(target, dependencies, zone)) {
                 if (changeTargetTo(target, application, zone)) {
                     upgrade(target, application, zone);
                 }
@@ -89,21 +110,21 @@ public abstract class InfrastructureUpgrader<VERSION> extends ControllerMaintain
         return converged;
     }
 
-    private boolean convergedOn(VERSION target, List<SystemApplication> applications, ZoneApi zone) {
+    private boolean convergedOn(TARGET target, Set<SystemApplication> applications, ZoneApi zone) {
         return applications.stream().allMatch(application -> convergedOn(target, application, zone));
     }
 
     /** Returns whether target version for application in zone should be changed */
-    protected abstract boolean changeTargetTo(VERSION target, SystemApplication application, ZoneApi zone);
+    protected abstract boolean changeTargetTo(TARGET target, SystemApplication application, ZoneApi zone);
 
     /** Upgrade component to target version. Implementation should be idempotent */
-    protected abstract void upgrade(VERSION target, SystemApplication application, ZoneApi zone);
+    protected abstract void upgrade(TARGET target, SystemApplication application, ZoneApi zone);
 
     /** Returns whether application has converged to target version in zone */
-    protected abstract boolean convergedOn(VERSION target, SystemApplication application, ZoneApi zone);
+    protected abstract boolean convergedOn(TARGET target, SystemApplication application, ZoneApi zone);
 
-    /** Returns the target version for the component upgraded by this, if any */
-    protected abstract Optional<VERSION> targetVersion();
+    /** Returns the version target for the component upgraded by this, if any */
+    protected abstract Optional<TARGET> target();
 
     /** Returns whether the upgrader should expect given node to upgrade */
     protected abstract boolean expectUpgradeOf(Node node, SystemApplication application, ZoneApi zone);