Add optional delay parameter to no-op step

CHANGELOG.md

@@ -17,6 +17,7 @@ Inspired from [Keep a Changelog](https://keepachangelog.com/en/1.1.0/)
 ### Enhancements
 - Add guardrails to default use case params ([#658](https://github.com/opensearch-project/flow-framework/pull/658))
 - Allow strings for boolean workflow step parameters ([#671](https://github.com/opensearch-project/flow-framework/pull/671))
+- Add optional delay parameter to no-op step ([#674](https://github.com/opensearch-project/flow-framework/pull/674))
 
 ### Bug Fixes
 - Reset workflow state to initial state after successful deprovision ([#635](https://github.com/opensearch-project/flow-framework/pull/635))

src/main/java/org/opensearch/flowframework/common/CommonValue.java

@@ -170,6 +170,8 @@ private CommonValue() {}
     public static final String CONFIGURATIONS = "configurations";
     /** Guardrails field */
     public static final String GUARDRAILS_FIELD = "guardrails";
+    /** Delay field */
+    public static final String DELAY_FIELD = "delay";
 
     /*
      * Constants associated with resource provisioning / state

src/main/java/org/opensearch/flowframework/workflow/NoOpStep.java

@@ -9,8 +9,17 @@
 package org.opensearch.flowframework.workflow;
 
 import org.opensearch.action.support.PlainActionFuture;
+import org.opensearch.common.unit.TimeValue;
+import org.opensearch.common.util.concurrent.FutureUtils;
+import org.opensearch.core.rest.RestStatus;
+import org.opensearch.flowframework.exception.WorkflowStepException;
+import org.opensearch.flowframework.util.ParseUtils;
 
+import java.util.Collections;
 import java.util.Map;
+import java.util.Set;
+
+import static org.opensearch.flowframework.common.CommonValue.DELAY_FIELD;
 
 /**
  * A workflow step that does nothing. May be used for synchronizing other actions.
@@ -32,6 +41,29 @@ public PlainActionFuture<WorkflowData> execute(
         Map<String, String> params
     ) {
         PlainActionFuture<WorkflowData> future = PlainActionFuture.newFuture();
+
+        Set<String> requiredKeys = Collections.emptySet();
+        Set<String> optionalKeys = Set.of(DELAY_FIELD);
+
+        try {
+            Map<String, Object> inputs = ParseUtils.getInputsFromPreviousSteps(
+                requiredKeys,
+                optionalKeys,
+                currentNodeInputs,
+                outputs,
+                previousNodeInputs,
+                params
+            );
+            if (inputs.containsKey(DELAY_FIELD)) {
+                long delay = TimeValue.parseTimeValue(inputs.get(DELAY_FIELD).toString(), DELAY_FIELD).millis();
+                Thread.sleep(delay);
+            }
+        } catch (IllegalArgumentException iae) {
+            throw new WorkflowStepException(iae.getMessage(), RestStatus.BAD_REQUEST);
+        } catch (InterruptedException e) {
+            FutureUtils.cancel(future);
+        }
+
         future.onResponse(WorkflowData.EMPTY);
         return future;
     }

src/test/java/org/opensearch/flowframework/workflow/NoOpStepTests.java

@@ -9,10 +9,14 @@
 package org.opensearch.flowframework.workflow;
 
 import org.opensearch.action.support.PlainActionFuture;
+import org.opensearch.flowframework.exception.WorkflowStepException;
 import org.opensearch.test.OpenSearchTestCase;
 
 import java.io.IOException;
 import java.util.Collections;
+import java.util.Map;
+
+import static org.opensearch.flowframework.common.CommonValue.DELAY_FIELD;
 
 public class NoOpStepTests extends OpenSearchTestCase {
 
@@ -28,4 +32,32 @@ public void testNoOpStep() throws IOException {
         );
         assertTrue(future.isDone());
     }
+
+    public void testNoOpStepDelay() throws IOException, InterruptedException {
+        NoOpStep noopStep = new NoOpStep();
+        WorkflowData delayData = new WorkflowData(Map.of(DELAY_FIELD, "1s"), null, null);
+
+        long start = System.nanoTime();
+        PlainActionFuture<WorkflowData> future = noopStep.execute(
+            "nodeId",
+            delayData,
+            Collections.emptyMap(),
+            Collections.emptyMap(),
+            Collections.emptyMap()
+        );
+        assertTrue(future.isDone());
+        // Sleep isn't exactly accurate so leave 100ms of roundoff
+        assertTrue(System.nanoTime() - start > 900_000_000L);
+    }
+
+    public void testNoOpStepParse() throws IOException {
+        NoOpStep noopStep = new NoOpStep();
+        WorkflowData delayData = new WorkflowData(Map.of(DELAY_FIELD, "foo"), null, null);
+
+        Exception ex = assertThrows(
+            WorkflowStepException.class,
+            () -> noopStep.execute("nodeId", delayData, Collections.emptyMap(), Collections.emptyMap(), Collections.emptyMap())
+        );
+        assertEquals("failed to parse setting [delay] with value [foo] as a time value: unit is missing or unrecognized", ex.getMessage());
+    }
 }