Adds owner field in monitor model (opensearch-project#313)

Signed-off-by: Surya Sashank Nistala <snistala@amazon.com>

Signed-off-by: Surya Sashank Nistala <snistala@amazon.com>

Author: eirsep

src/main/kotlin/org/opensearch/commons/alerting/model/Monitor.kt

@@ -40,7 +40,8 @@ data class Monitor(
     val inputs: List<Input>,
     val triggers: List<Trigger>,
     val uiMetadata: Map<String, Any>,
-    val dataSources: DataSources = DataSources()
+    val dataSources: DataSources = DataSources(),
+    val owner: String? = "alerting"
 ) : ScheduledJob {
 
     override val type = MONITOR_TYPE
@@ -102,7 +103,8 @@ data class Monitor(
             DataSources(sin)
         } else {
             DataSources()
-        }
+        },
+        owner = sin.readOptionalString()
     )
 
     // This enum classifies different Monitors
@@ -151,6 +153,7 @@ data class Monitor(
             .optionalTimeField(LAST_UPDATE_TIME_FIELD, lastUpdateTime)
         if (uiMetadata.isNotEmpty()) builder.field(UI_METADATA_FIELD, uiMetadata)
         builder.field(DATA_SOURCES_FIELD, dataSources)
+        builder.field(OWNER_FIELD, owner)
         if (params.paramAsBoolean("with_type", false)) builder.endObject()
         return builder.endObject()
     }
@@ -195,6 +198,7 @@ data class Monitor(
         out.writeMap(uiMetadata)
         out.writeBoolean(dataSources != null) // for backward compatibility with pre-existing monitors which don't have datasources field
         dataSources.writeTo(out)
+        out.writeOptionalString(owner)
     }
 
     companion object {
@@ -214,6 +218,7 @@ data class Monitor(
         const val UI_METADATA_FIELD = "ui_metadata"
         const val DATA_SOURCES_FIELD = "data_sources"
         const val ENABLED_TIME_FIELD = "enabled_time"
+        const val OWNER_FIELD = "owner"
 
         // This is defined here instead of in ScheduledJob to avoid having the ScheduledJob class know about all
         // the different subclasses and creating circular dependencies
@@ -240,6 +245,7 @@ data class Monitor(
             val triggers: MutableList<Trigger> = mutableListOf()
             val inputs: MutableList<Input> = mutableListOf()
             var dataSources = DataSources()
+            var owner = "alerting"
 
             XContentParserUtils.ensureExpectedToken(XContentParser.Token.START_OBJECT, xcp.currentToken(), xcp)
             while (xcp.nextToken() != XContentParser.Token.END_OBJECT) {
@@ -287,6 +293,7 @@ data class Monitor(
                     UI_METADATA_FIELD -> uiMetadata = xcp.map()
                     DATA_SOURCES_FIELD -> dataSources = if (xcp.currentToken() == XContentParser.Token.VALUE_NULL) DataSources()
                     else DataSources.parse(xcp)
+                    OWNER_FIELD -> owner = if (xcp.currentToken() == XContentParser.Token.VALUE_NULL) owner else xcp.text()
                     else -> {
                         xcp.skipChildren()
                     }
@@ -312,7 +319,8 @@ data class Monitor(
                 inputs.toList(),
                 triggers.toList(),
                 uiMetadata,
-                dataSources
+                dataSources,
+                owner
             )
         }