acknowledge chained alert request for workflow (#459)

Signed-off-by: Surya Sashank Nistala <[email protected]>

Author: eirsep

src/main/kotlin/org/opensearch/commons/alerting/action/AcknowledgeChainedAlertRequest.kt

@@ -0,0 +1,43 @@
+/*
+ * Copyright OpenSearch Contributors
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+package org.opensearch.commons.alerting.action
+
+import org.opensearch.action.ActionRequest
+import org.opensearch.action.ActionRequestValidationException
+import org.opensearch.common.io.stream.StreamInput
+import org.opensearch.common.io.stream.StreamOutput
+import java.io.IOException
+import java.util.Collections
+
+/** Request DTO for acknowledging chained alerts generated by workflow.*/
+class AcknowledgeChainedAlertRequest : ActionRequest {
+    val workflowId: String
+    val alertIds: List<String>
+
+    constructor(
+        workflowId: String,
+        alertIds: List<String>,
+    ) : super() {
+        this.workflowId = workflowId
+        this.alertIds = alertIds
+    }
+
+    @Throws(IOException::class)
+    constructor(sin: StreamInput) : this(
+        sin.readString(), // workflowId
+        Collections.unmodifiableList(sin.readStringList()), // alertIds
+    )
+
+    override fun validate(): ActionRequestValidationException? {
+        return null
+    }
+
+    @Throws(IOException::class)
+    override fun writeTo(out: StreamOutput) {
+        out.writeString(workflowId)
+        out.writeStringCollection(alertIds)
+    }
+}

src/test/kotlin/org/opensearch/commons/alerting/action/AcknowledgeChainedAlertRequestTests.kt

@@ -0,0 +1,27 @@
+/*
+ * Copyright OpenSearch Contributors
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+package org.opensearch.commons.alerting.action
+
+import org.junit.jupiter.api.Assertions.assertEquals
+import org.junit.jupiter.api.Assertions.assertNotNull
+import org.junit.jupiter.api.Test
+import org.opensearch.common.io.stream.BytesStreamOutput
+import org.opensearch.common.io.stream.StreamInput
+
+class AcknowledgeChainedAlertRequestTests {
+
+    @Test
+    fun `test acknowledge chained alert request`() {
+        val req = AcknowledgeChainedAlertRequest("1234", mutableListOf("1", "2", "3", "4"))
+        assertNotNull(req)
+        val out = BytesStreamOutput()
+        req.writeTo(out)
+        val sin = StreamInput.wrap(out.bytes().toBytesRef().bytes)
+        val newReq = AcknowledgeChainedAlertRequest(sin)
+        assertEquals("1234", newReq.workflowId)
+        assertEquals(4, newReq.alertIds.size)
+    }
+}