Check target OS version per zone

This change makes the controller check the target OS version per zone (retrieved
from `/nodes/v2/upgrade/`) when deciding whether to set a target.

In the node repository, the OS version value in `/nodes/v2/upgrade/` and the value of
each nodes `wantedOsVersion` are backed by the same ZK data.

To implement automatic pausing of OS upgrades we'll eventually start omitting
the `wantedOsVersion` node field when an OS version is deactivated. We therefore
make the controller read target version from `/nodes/v2/upgrade/` instead to
avoid the controller repeatedly setting a target version while upgrades to that
version are paused.

2 files changed, 70 insertions, 0 deletions

diff --git a/controller-api/src/main/java/com/yahoo/vespa/hosted/controller/api/integration/configserver/NodeRepository.java b/controller-api/src/main/java/com/yahoo/vespa/hosted/controller/api/integration/configserver/NodeRepository.java
index e9b0c69e904..b36eba7d063 100644
--- a/controller-api/src/main/java/com/yahoo/vespa/hosted/controller/api/integration/configserver/NodeRepository.java
+++ b/controller-api/src/main/java/com/yahoo/vespa/hosted/controller/api/integration/configserver/NodeRepository.java
@@ -62,6 +62,9 @@ public interface NodeRepository {
     /** Upgrade OS for all nodes of given type to a new version */
     void upgradeOs(ZoneId zone, NodeType type, Version version);
 
+    /** Get target versions for upgrades in given zone */
+    TargetVersions targetVersionsOf(ZoneId zone);
+
     /** Requests firmware checks on all hosts in the given zone. */
     void requestFirmwareCheck(ZoneId zone);
 
diff --git a/controller-api/src/main/java/com/yahoo/vespa/hosted/controller/api/integration/configserver/TargetVersions.java b/controller-api/src/main/java/com/yahoo/vespa/hosted/controller/api/integration/configserver/TargetVersions.java
new file mode 100644
index 00000000000..a14792241fc
--- /dev/null
+++ b/controller-api/src/main/java/com/yahoo/vespa/hosted/controller/api/integration/configserver/TargetVersions.java
@@ -0,0 +1,67 @@
+// Copyright 2019 Oath Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.hosted.controller.api.integration.configserver;
+
+import com.yahoo.component.Version;
+import com.yahoo.config.provision.NodeType;
+
+import java.util.HashMap;
+import java.util.Map;
+import java.util.Objects;
+import java.util.Optional;
+
+/**
+ * Target versions for node upgrades in a zone.
+ *
+ * @author mpolden
+ */
+public class TargetVersions {
+
+    public static final TargetVersions EMPTY = new TargetVersions(Map.of(), Map.of());
+
+    private final Map<NodeType, Version> vespaVersions;
+    private final Map<NodeType, Version> osVersions;
+
+    public TargetVersions(Map<NodeType, Version> vespaVersions, Map<NodeType, Version> osVersions) {
+        this.vespaVersions = Map.copyOf(Objects.requireNonNull(vespaVersions, "vespaVersions must be non-null"));
+        this.osVersions = Map.copyOf(Objects.requireNonNull(osVersions, "osVersions must be non-null"));
+    }
+
+    /** Returns a copy of this with Vespa version set for given node type */
+    public TargetVersions withVespaVersion(NodeType nodeType, Version version) {
+        var vespaVersions = new HashMap<>(this.vespaVersions);
+        vespaVersions.put(nodeType, version);
+        return new TargetVersions(vespaVersions, osVersions);
+    }
+
+    /** Returns a copy of this with OS version set for given node type */
+    public TargetVersions withOsVersion(NodeType nodeType, Version version) {
+        var osVersions = new HashMap<>(this.osVersions);
+        osVersions.put(nodeType, version);
+        return new TargetVersions(vespaVersions, osVersions);
+    }
+
+    /** Returns the target OS version of given node type, if any */
+    public Optional<Version> osVersion(NodeType type) {
+        return Optional.ofNullable(osVersions.get(type));
+    }
+
+    /** Returns the target Vespa version of given node type, if any */
+    public Optional<Version> vespaVersion(NodeType type) {
+        return Optional.ofNullable(vespaVersions.get(type));
+    }
+
+    @Override
+    public boolean equals(Object o) {
+        if (this == o) return true;
+        if (o == null || getClass() != o.getClass()) return false;
+        TargetVersions that = (TargetVersions) o;
+        return vespaVersions.equals(that.vespaVersions) &&
+               osVersions.equals(that.osVersions);
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(vespaVersions, osVersions);
+    }
+
+}