Make it possible to configure and change status code in /state/v1/health API

Make inital value configurable and make it possible to get and set it
in StateMonitor

3 files changed, 24 insertions, 9 deletions

diff --git a/container-core/src/main/java/com/yahoo/container/jdisc/state/StateHandler.java b/container-core/src/main/java/com/yahoo/container/jdisc/state/StateHandler.java
index ce9779b83d9..23c247fa438 100644
--- a/container-core/src/main/java/com/yahoo/container/jdisc/state/StateHandler.java
+++ b/container-core/src/main/java/com/yahoo/container/jdisc/state/StateHandler.java
@@ -190,7 +190,7 @@ public class StateHandler extends AbstractRequestHandler {
     private JSONObjectWithLegibleException buildJsonForConsumer(String consumer) throws JSONException {
         JSONObjectWithLegibleException ret = new JSONObjectWithLegibleException();
         ret.put("time", timer.currentTimeMillis());
-        ret.put("status", new JSONObjectWithLegibleException().put("code", "up"));
+        ret.put("status", new JSONObjectWithLegibleException().put("code", getStatus().name()));
         ret.put(METRICS_PATH, buildJsonForSnapshot(consumer, getSnapshot()));
         return ret;
     }
@@ -203,6 +203,10 @@ public class StateHandler extends AbstractRequestHandler {
         }
     }
 
+    private StateMonitor.Status getStatus() {
+        return monitor.status();
+    }
+
     private JSONObjectWithLegibleException buildJsonForSnapshot(String consumer, MetricSnapshot metricSnapshot) throws JSONException {
         if (metricSnapshot == null) {
             return new JSONObjectWithLegibleException();
diff --git a/container-core/src/main/java/com/yahoo/container/jdisc/state/StateMonitor.java b/container-core/src/main/java/com/yahoo/container/jdisc/state/StateMonitor.java
index 140257cbcef..9af9956df06 100644
--- a/container-core/src/main/java/com/yahoo/container/jdisc/state/StateMonitor.java
+++ b/container-core/src/main/java/com/yahoo/container/jdisc/state/StateMonitor.java
@@ -14,7 +14,7 @@ import java.util.concurrent.TimeUnit;
 import java.util.logging.Logger;
 
 /**
- * A statemonitor keeps track of the current metrics state of a container.
+ * A state monitor keeps track of the current health and metrics state of a container.
  * It is used by jDisc to hand out metric update API endpoints to workers through {@link #newMetricConsumer},
  * and to inspect the current accumulated state of metrics through {@link #snapshot}.
  *
@@ -23,12 +23,16 @@ import java.util.logging.Logger;
 public class StateMonitor extends AbstractComponent {
 
     private final static Logger log = Logger.getLogger(StateMonitor.class.getName());
+
+    public enum Status {up, down, initializing};
+
     private final CopyOnWriteArrayList<StateMetricConsumer> consumers = new CopyOnWriteArrayList<>();
     private final Thread thread;
     private final Timer timer;
     private final long snapshotIntervalMs;
     private long lastSnapshotTimeMs;
     private volatile MetricSnapshot snapshot;
+    private volatile Status status;
     private final TreeSet<String> valueNames = new TreeSet<>();
 
     @Inject
@@ -36,13 +40,9 @@ public class StateMonitor extends AbstractComponent {
         this.timer = timer;
         this.snapshotIntervalMs = (long)(config.snapshot_interval() * TimeUnit.SECONDS.toMillis(1));
         this.lastSnapshotTimeMs = timer.currentTimeMillis();
-        thread = new Thread(new Runnable() {
-
-            @Override
-            public void run() {
-                StateMonitor.this.run();
-            }
-        }, "StateMonitor");
+        this.status = Status.valueOf(config.initialStatus());
+        System.out.println("Initial status: " + status);
+        thread = new Thread(StateMonitor.this::run, "StateMonitor");
         thread.setDaemon(true);
         thread.start();
     }
@@ -54,6 +54,14 @@ public class StateMonitor extends AbstractComponent {
         return consumer;
     }
 
+    public void status(Status status) {
+        this.status = status;
+        }
+
+    public Status status() {
+        return status;
+    }
+
     /** Returns the last snapshot taken of the metrics in this system */
     public MetricSnapshot snapshot() {
         return snapshot;
diff --git a/container-core/src/main/resources/configdefinitions/health-monitor.def b/container-core/src/main/resources/configdefinitions/health-monitor.def
index dc5cdbc6ca4..5e70c72ae3f 100644
--- a/container-core/src/main/resources/configdefinitions/health-monitor.def
+++ b/container-core/src/main/resources/configdefinitions/health-monitor.def
@@ -4,3 +4,6 @@ namespace=container.jdisc.config
 
 # How far between snapshots. 5 minutes by default
 snapshot_interval double default=300
+
+# Initial status used in /state/v1/health API (value for 'code' in 'status'). See StateMonitor for valid values
+initialStatus string default="up"