Metadata about /state/v1/health status

The service monitor uses /state/v1/health to monitor config servers and the
host admins (but not yet tenant host admins).

This commit adds some metadata about the status of a service:
 - The time the status was last checked
 - The time the status changed to the current

This can be used to e.g. make more intelligent decisions in the Orchestrator,
e.g. only allowing a service to suspend if it has been DOWN longer than X
seconds (to avoid spurious DOWN to break redundancy and uptime guarantees).

2 files changed, 108 insertions, 7 deletions

diff --git a/application-model/src/main/java/com/yahoo/vespa/applicationmodel/ServiceInstance.java b/application-model/src/main/java/com/yahoo/vespa/applicationmodel/ServiceInstance.java
index 80178f79bb1..b4fce878b0d 100644
--- a/application-model/src/main/java/com/yahoo/vespa/applicationmodel/ServiceInstance.java
+++ b/application-model/src/main/java/com/yahoo/vespa/applicationmodel/ServiceInstance.java
@@ -14,13 +14,17 @@ public class ServiceInstance {
 
     private final ConfigId configId;
     private final HostName hostName;
-    private final ServiceStatus serviceStatus;
+    private final ServiceStatusInfo serviceStatusInfo;
     private Optional<ServiceCluster> serviceCluster = Optional.empty();
 
     public ServiceInstance(ConfigId configId, HostName hostName, ServiceStatus serviceStatus) {
+        this(configId, hostName, new ServiceStatusInfo(serviceStatus));
+    }
+
+    public ServiceInstance(ConfigId configId, HostName hostName, ServiceStatusInfo serviceStatusInfo) {
         this.configId = configId;
         this.hostName = hostName;
-        this.serviceStatus = serviceStatus;
+        this.serviceStatusInfo = serviceStatusInfo;
     }
 
     @JsonProperty("configId")
@@ -33,9 +37,13 @@ public class ServiceInstance {
         return hostName;
     }
 
-    @JsonProperty("serviceStatus")
     public ServiceStatus serviceStatus() {
-        return serviceStatus;
+        return serviceStatusInfo.serviceStatus();
+    }
+
+    @JsonProperty("serviceStatusInfo")
+    public ServiceStatusInfo serviceStatusInfo() {
+        return serviceStatusInfo;
     }
 
     @JsonIgnore
@@ -50,10 +58,11 @@ public class ServiceInstance {
 
     @Override
     public String toString() {
+        // serviceCluster omitted to avoid recursion
         return "ServiceInstance{" +
                 "configId=" + configId +
                 ", hostName=" + hostName +
-                ", serviceStatus=" + serviceStatus +
+                ", serviceStatus=" + serviceStatusInfo +
                 '}';
     }
 
@@ -62,13 +71,15 @@ public class ServiceInstance {
         if (this == o) return true;
         if (o == null || getClass() != o.getClass()) return false;
         ServiceInstance that = (ServiceInstance) o;
+        // serviceCluster omitted to avoid recursion
         return Objects.equals(configId, that.configId) &&
                 Objects.equals(hostName, that.hostName) &&
-                serviceStatus == that.serviceStatus;
+                serviceStatusInfo == that.serviceStatusInfo;
     }
 
     @Override
     public int hashCode() {
-        return Objects.hash(configId, hostName, serviceStatus);
+        // serviceCluster omitted to avoid recursion
+        return Objects.hash(configId, hostName, serviceStatusInfo);
     }
 }
diff --git a/application-model/src/main/java/com/yahoo/vespa/applicationmodel/ServiceStatusInfo.java b/application-model/src/main/java/com/yahoo/vespa/applicationmodel/ServiceStatusInfo.java
new file mode 100644
index 00000000000..da2b1bb6ad8
--- /dev/null
+++ b/application-model/src/main/java/com/yahoo/vespa/applicationmodel/ServiceStatusInfo.java
@@ -0,0 +1,90 @@
+// Copyright 2019 Oath Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.applicationmodel;
+
+import com.fasterxml.jackson.annotation.JsonInclude;
+import com.fasterxml.jackson.annotation.JsonProperty;
+
+import java.time.Instant;
+import java.util.Objects;
+import java.util.Optional;
+
+/**
+ * @author hakonhall
+ */
+@JsonInclude(value = JsonInclude.Include.NON_NULL)
+public class ServiceStatusInfo {
+    private final ServiceStatus status;
+    private final Optional<Instant> since;
+    private final Optional<Instant> lastChecked;
+    private final Optional<String> error;
+
+    public ServiceStatusInfo(ServiceStatus status) {
+        this(status, Optional.empty(), Optional.empty(), Optional.empty());
+    }
+
+    public ServiceStatusInfo(ServiceStatus status, Instant since, Instant lastChecked, Optional<String> error) {
+        this(status, Optional.of(since), Optional.of(lastChecked), error);
+    }
+
+    public ServiceStatusInfo(ServiceStatus status, Optional<Instant> since, Optional<Instant> lastChecked,
+                             Optional<String> error) {
+        this.status = status;
+        this.since = since;
+        this.lastChecked = lastChecked;
+        this.error = error;
+    }
+
+    @JsonProperty("serviceStatus")
+    public ServiceStatus serviceStatus() {
+        return status;
+    }
+
+    /** The current service status was first seen at this time, and has since stayed constant. */
+    public Optional<Instant> since() {
+        return since;
+    }
+
+    @JsonProperty("since")
+    public Instant sinceOrNull() {
+        return since.orElse(null);
+    }
+
+    /** The last time the status was checked. */
+    public Optional<Instant> lastChecked() {
+        return lastChecked;
+    }
+
+    @JsonProperty("lastChecked")
+    public Instant lastCheckedOrNull() {
+        return lastChecked.orElse(null);
+    }
+
+    @JsonProperty("error")
+    public String errorOrNull() {
+        return error.orElse(null);
+    }
+
+    @Override
+    public String toString() {
+        return "ServiceStatusInfo{" +
+                "status=" + status +
+                ", since=" + since +
+                ", lastChecked=" + lastChecked +
+                '}';
+    }
+
+    @Override
+    public boolean equals(Object o) {
+        if (this == o) return true;
+        if (o == null || getClass() != o.getClass()) return false;
+        ServiceStatusInfo that = (ServiceStatusInfo) o;
+        return status == that.status &&
+                Objects.equals(since, that.since) &&
+                Objects.equals(lastChecked, that.lastChecked);
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(status, since, lastChecked);
+    }
+}