[Backport 2.x] Implemented cross-cluster monitor support #584

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

@@ -43,6 +43,7 @@
     val aggregationResultBucket: AggregationResultBucket? = null,
     val executionId: String? = null,
     val associatedAlertIds: List<String>,
+    val clusters: List<String>? = null,
 ) : Writeable, ToXContent {
 
     init {
@@ -61,6 +62,7 @@
         chainedAlertTrigger: ChainedAlertTrigger,
         workflow: Workflow,
         associatedAlertIds: List<String>,
+        clusters: List<String>? = null
     ) : this(
         monitorId = NO_ID,
         monitorName = "",
@@ -82,7 +84,8 @@
         executionId = executionId,
         workflowId = workflow.id,
         workflowName = workflow.name,
-        associatedAlertIds = associatedAlertIds
+        associatedAlertIds = associatedAlertIds,
+        clusters = clusters
     )
 
     constructor(
@@ -97,6 +100,7 @@
         schemaVersion: Int = NO_SCHEMA_VERSION,
         executionId: String? = null,
         workflowId: String? = null,
+        clusters: List<String>? = null
     ) : this(
         monitorId = monitor.id,
         monitorName = monitor.name,
@@ -118,7 +122,8 @@
         executionId = executionId,
         workflowId = workflowId ?: "",
         workflowName = "",
-        associatedAlertIds = emptyList()
+        associatedAlertIds = emptyList(),
+        clusters = clusters
     )
 
     constructor(
@@ -134,6 +139,7 @@
         findingIds: List<String> = emptyList(),
         executionId: String? = null,
         workflowId: String? = null,
+        clusters: List<String>? = null
     ) : this(
         monitorId = monitor.id,
         monitorName = monitor.name,
@@ -155,7 +161,8 @@
         executionId = executionId,
         workflowId = workflowId ?: "",
         workflowName = "",
-        associatedAlertIds = emptyList()
+        associatedAlertIds = emptyList(),
+        clusters = clusters
     )
 
     constructor(
@@ -172,6 +179,7 @@
         findingIds: List<String> = emptyList(),
         executionId: String? = null,
         workflowId: String? = null,
+        clusters: List<String>? = null
     ) : this(
         monitorId = monitor.id,
         monitorName = monitor.name,
@@ -193,7 +201,8 @@
         executionId = executionId,
         workflowId = workflowId ?: "",
         workflowName = "",
-        associatedAlertIds = emptyList()
+        associatedAlertIds = emptyList(),
+        clusters = clusters
     )
 
     constructor(
@@ -211,6 +220,7 @@
         schemaVersion: Int = NO_SCHEMA_VERSION,
         executionId: String? = null,
         workflowId: String? = null,
+        clusters: List<String>? = null
     ) : this(
         id = id,
         monitorId = monitor.id,
@@ -233,7 +243,8 @@
         executionId = executionId,
         workflowId = workflowId ?: "",
         workflowName = "",
-        associatedAlertIds = emptyList()
+        associatedAlertIds = emptyList(),
+        clusters = clusters
     )
 
     constructor(
@@ -248,6 +259,7 @@
         schemaVersion: Int = NO_SCHEMA_VERSION,
         workflowId: String? = null,
         executionId: String?,
+        clusters: List<String>? = null
     ) : this(
         id = id,
         monitorId = monitor.id,
@@ -270,7 +282,8 @@
         relatedDocIds = listOf(),
         workflowId = workflowId ?: "",
         executionId = executionId,
-        associatedAlertIds = emptyList()
+        associatedAlertIds = emptyList(),
+        clusters = clusters
     )
 
     enum class State {
@@ -311,7 +324,8 @@
         actionExecutionResults = sin.readList(::ActionExecutionResult),
         aggregationResultBucket = if (sin.readBoolean()) AggregationResultBucket(sin) else null,
         executionId = sin.readOptionalString(),
-        associatedAlertIds = sin.readStringList()
+        associatedAlertIds = sin.readStringList(),
+        clusters = sin.readOptionalStringList()
     )
 
     fun isAcknowledged(): Boolean = (state == State.ACKNOWLEDGED)
@@ -349,6 +363,7 @@
         }
         out.writeOptionalString(executionId)
         out.writeStringCollection(associatedAlertIds)
+        out.writeOptionalStringArray(clusters?.toTypedArray())
     }
 
     companion object {
@@ -379,6 +394,7 @@
         const val ASSOCIATED_ALERT_IDS_FIELD = "associated_alert_ids"
         const val BUCKET_KEYS = AggregationResultBucket.BUCKET_KEYS
         const val PARENTS_BUCKET_PATH = AggregationResultBucket.PARENTS_BUCKET_PATH
+        const val CLUSTERS_FIELD = "clusters"
         const val NO_ID = ""
         const val NO_VERSION = Versions.NOT_FOUND
 
@@ -409,6 +425,7 @@
             val actionExecutionResults: MutableList<ActionExecutionResult> = mutableListOf()
             var aggAlertBucket: AggregationResultBucket? = null
             val associatedAlertIds = mutableListOf<String>()
+            val clusters = mutableListOf<String>()
             ensureExpectedToken(XContentParser.Token.START_OBJECT, xcp.currentToken(), xcp)
             while (xcp.nextToken() != XContentParser.Token.END_OBJECT) {
                 val fieldName = xcp.currentName()
@@ -475,6 +492,12 @@
                             AggregationResultBucket.parse(xcp)
                         }
                     }
+                    CLUSTERS_FIELD -> {
+                        ensureExpectedToken(XContentParser.Token.START_ARRAY, xcp.currentToken(), xcp)
+                        while (xcp.nextToken() != XContentParser.Token.END_ARRAY) {
+                            clusters.add(xcp.text())
+                        }
+                    }
                 }
             }
 
@@ -503,7 +526,8 @@
                 executionId = executionId,
                 workflowId = workflowId,
                 workflowName = workflowName,
-                associatedAlertIds = associatedAlertIds
+                associatedAlertIds = associatedAlertIds,
+                clusters = if (clusters.size > 0) clusters else null
             )
         }
 
@@ -553,6 +577,9 @@
             .optionalTimeField(END_TIME_FIELD, endTime)
             .optionalTimeField(ACKNOWLEDGED_TIME_FIELD, acknowledgedTime)
         aggregationResultBucket?.innerXContent(builder)
+
+        if (!clusters.isNullOrEmpty()) builder.field(CLUSTERS_FIELD, clusters.toTypedArray())
+
         builder.endObject()
         return builder
     }
@@ -576,7 +603,8 @@
             BUCKET_KEYS to aggregationResultBucket?.bucketKeys?.joinToString(","),
             PARENTS_BUCKET_PATH to aggregationResultBucket?.parentBucketPath,
             FINDING_IDS to findingIds.joinToString(","),
-            RELATED_DOC_IDS to relatedDocIds.joinToString(",")
+            RELATED_DOC_IDS to relatedDocIds.joinToString(","),
+            CLUSTERS_FIELD to clusters?.joinToString(",")
         )
     }
 }

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

@@ -13,6 +13,7 @@
 import org.opensearch.core.xcontent.XContentParserUtils
 import java.io.IOException
 import java.net.URI
+import java.net.URISyntaxException
 
 val ILLEGAL_PATH_PARAMETER_CHARACTERS = arrayOf(':', '"', '+', '\\', '|', '?', '#', '>', '<', ' ')
 
@@ -22,7 +23,8 @@
 data class ClusterMetricsInput(
     var path: String,
     var pathParams: String = "",
-    var url: String
+    var url: String,
+    var clusters: List<String> = listOf()
 ) : Input {
     val clusterMetricType: ClusterMetricType
     val constructedUri: URI
@@ -43,11 +45,10 @@
             "Invalid URI constructed from the path and path_params inputs, or the url input."
         }
 
-        if (url.isNotEmpty() && validateFieldsNotEmpty()) {
+        if (url.isNotEmpty() && validateFieldsNotEmpty())
             require(constructedUri == constructUrlFromInputs()) {
                 "The provided URL and URI fields form different URLs."
             }
-        }
 
         require(constructedUri.host.lowercase() == SUPPORTED_HOST) {
             "Only host '$SUPPORTED_HOST' is supported."
@@ -74,6 +75,7 @@
             .field(PATH_FIELD, path)
             .field(PATH_PARAMS_FIELD, pathParams)
             .field(URL_FIELD, url)
+            .field(CLUSTERS_FIELD, clusters)
             .endObject()
             .endObject()
     }
@@ -87,6 +89,7 @@
         out.writeString(path)
         out.writeString(pathParams)
         out.writeString(url)
+        out.writeStringArray(clusters.toTypedArray())
     }
 
     companion object {
@@ -99,18 +102,19 @@
         const val PATH_PARAMS_FIELD = "path_params"
         const val URL_FIELD = "url"
         const val URI_FIELD = "uri"
+        const val CLUSTERS_FIELD = "clusters"
 
         val XCONTENT_REGISTRY = NamedXContentRegistry.Entry(Input::class.java, ParseField(URI_FIELD), CheckedFunction { parseInner(it) })
 
         /**
          * This parse function uses [XContentParser] to parse JSON input and store corresponding fields to create a [ClusterMetricsInput] object
          */
-        @JvmStatic
-        @Throws(IOException::class)
+        @JvmStatic @Throws(IOException::class)
         fun parseInner(xcp: XContentParser): ClusterMetricsInput {
             var path = ""
             var pathParams = ""
             var url = ""
+            val clusters = mutableListOf<String>()
 
             XContentParserUtils.ensureExpectedToken(XContentParser.Token.START_OBJECT, xcp.currentToken(), xcp)
 
@@ -121,9 +125,17 @@
                     PATH_FIELD -> path = xcp.text()
                     PATH_PARAMS_FIELD -> pathParams = xcp.text()
                     URL_FIELD -> url = xcp.text()
+                    CLUSTERS_FIELD -> {
+                        XContentParserUtils.ensureExpectedToken(
+                            XContentParser.Token.START_ARRAY,
+                            xcp.currentToken(),
+                            xcp
+                        )
+                        while (xcp.nextToken() != XContentParser.Token.END_ARRAY) clusters.add(xcp.text())
+                    }
                 }
             }
-            return ClusterMetricsInput(path, pathParams, url)
+            return ClusterMetricsInput(path, pathParams, url, clusters)
         }
     }
 
@@ -163,20 +175,17 @@
         if (pathParams.isNotEmpty()) {
             pathParams = pathParams.trim('/')
             ILLEGAL_PATH_PARAMETER_CHARACTERS.forEach { character ->
-                if (pathParams.contains(character)) {
+                if (pathParams.contains(character))
                     throw IllegalArgumentException(
-                        "The provided path parameters contain invalid characters or spaces. Please omit: " + "${ILLEGAL_PATH_PARAMETER_CHARACTERS.joinToString(" ")}"
+                        "The provided path parameters contain invalid characters or spaces. Please omit: " + ILLEGAL_PATH_PARAMETER_CHARACTERS.joinToString(" ")
                     )
-                }
             }
         }
 
-        if (apiType.requiresPathParams && pathParams.isEmpty()) {
+        if (apiType.requiresPathParams && pathParams.isEmpty())
             throw IllegalArgumentException("The API requires path parameters.")
-        }
-        if (!apiType.supportsPathParams && pathParams.isNotEmpty()) {
+        if (!apiType.supportsPathParams && pathParams.isNotEmpty())
             throw IllegalArgumentException("The API does not use path parameters.")
-        }
 
         return pathParams
     }
@@ -192,13 +201,11 @@
         ClusterMetricType.values()
             .filter { option -> option != ClusterMetricType.BLANK }
             .forEach { option ->
-                if (uriPath.startsWith(option.prependPath) || uriPath.startsWith(option.defaultPath)) {
+                if (uriPath.startsWith(option.prependPath) || uriPath.startsWith(option.defaultPath))
                     apiType = option
-                }
             }
-        if (apiType.isBlank()) {
+        if (apiType.isBlank())
             throw IllegalArgumentException("The API could not be determined from the provided URI.")
-        }
         return apiType
     }
 
@@ -207,28 +214,36 @@
      * @return The constructed [URI].
      */
     private fun constructUrlFromInputs(): URI {
-        val uriBuilder = URIBuilder()
-            .setScheme(SUPPORTED_SCHEME)
-            .setHost(SUPPORTED_HOST)
-            .setPort(SUPPORTED_PORT)
-            .setPath(path + pathParams)
-        return uriBuilder.build()
+        /**
+         * this try-catch block is required due to a httpcomponents 5.1.x library issue
+         * it auto encodes path params in the url.
+         */
+        return try {
+            val formattedPath = if (path.startsWith("/") || path.isBlank()) path else "/$path"
+            val formattedPathParams = if (pathParams.startsWith("/") || pathParams.isBlank()) pathParams else "/$pathParams"
+            val uriBuilder = URIBuilder("$SUPPORTED_SCHEME://$SUPPORTED_HOST:$SUPPORTED_PORT$formattedPath$formattedPathParams")
+            uriBuilder.build()
+        } catch (ex: URISyntaxException) {
+            val uriBuilder = URIBuilder()
+                .setScheme(SUPPORTED_SCHEME)
+                .setHost(SUPPORTED_HOST)
+                .setPort(SUPPORTED_PORT)
+                .setPath(path + pathParams)
+            uriBuilder.build()
+        }
     }
 
     /**
      * If [url] field is empty, populates it with [constructedUri].
      * If [path] and [pathParams] are empty, populates them with values from [url].
      */
     private fun parseEmptyFields() {
-        if (pathParams.isEmpty()) {
+        if (pathParams.isEmpty())
             pathParams = this.parsePathParams()
-        }
-        if (path.isEmpty()) {
+        if (path.isEmpty())
             path = if (pathParams.isEmpty()) clusterMetricType.defaultPath else clusterMetricType.prependPath
-        }
-        if (url.isEmpty()) {
+        if (url.isEmpty())
             url = constructedUri.toString()
-        }
     }
 
     /**

src/test/kotlin/org/opensearch/commons/alerting/AlertTests.kt

@@ -23,6 +23,7 @@ class AlertTests {
         assertEquals(templateArgs[Alert.START_TIME_FIELD], alert.startTime.toEpochMilli(), "Template args start time does not")
         assertEquals(templateArgs[Alert.LAST_NOTIFICATION_TIME_FIELD], null, "Template args last notification time does not match")
         assertEquals(templateArgs[Alert.SEVERITY_FIELD], alert.severity, "Template args severity does not match")
+        assertEquals(templateArgs[Alert.CLUSTERS_FIELD], alert.clusters?.joinToString(","), "Template args clusters does not match")
     }
 
     @Test
@@ -40,6 +41,7 @@ class AlertTests {
         assertEquals(templateArgs[Alert.START_TIME_FIELD], alert.startTime.toEpochMilli(), "Template args start time does not")
         assertEquals(templateArgs[Alert.LAST_NOTIFICATION_TIME_FIELD], null, "Template args last notification time does not match")
         assertEquals(templateArgs[Alert.SEVERITY_FIELD], alert.severity, "Template args severity does not match")
+        assertEquals(templateArgs[Alert.CLUSTERS_FIELD], alert.clusters?.joinToString(","), "Template args clusters does not match")
         assertEquals(
             templateArgs[Alert.BUCKET_KEYS],
             alert.aggregationResultBucket?.bucketKeys?.joinToString(","),