From 7a639601bd1bc7aed263969d402a59b05fe43984 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Lo=C3=AFc=20Mathieu?= <loikeseke@gmail.com>
Date: Tue, 30 Jul 2024 11:08:13 +0200
Subject: [PATCH] fix(core): ForEach graph should be sequential when
 concurrencyLimit=1

Fixes #4474
---
 .../io/kestra/plugin/core/flow/ForEach.java   | 26 ++++++++++++++-----
 1 file changed, 19 insertions(+), 7 deletions(-)

diff --git a/core/src/main/java/io/kestra/plugin/core/flow/ForEach.java b/core/src/main/java/io/kestra/plugin/core/flow/ForEach.java
index 8b76d4c020..5af633727c 100644
--- a/core/src/main/java/io/kestra/plugin/core/flow/ForEach.java
+++ b/core/src/main/java/io/kestra/plugin/core/flow/ForEach.java
@@ -18,6 +18,7 @@
 import io.kestra.core.utils.GraphUtils;
 import io.swagger.v3.oas.annotations.media.Schema;
 import jakarta.validation.constraints.NotNull;
+import jakarta.validation.constraints.PositiveOrZero;
 import lombok.*;
 import lombok.experimental.SuperBuilder;
 
@@ -147,6 +148,7 @@ public class ForEach extends Sequential implements FlowableTask<VoidOutput> {
     )
     private Object values;
 
+    @PositiveOrZero
     @NotNull
     @Builder.Default
     @Schema(
@@ -164,13 +166,23 @@ public class ForEach extends Sequential implements FlowableTask<VoidOutput> {
     public GraphCluster tasksTree(Execution execution, TaskRun taskRun, List<String> parentValues) throws IllegalVariableEvaluationException {
         GraphCluster subGraph = new GraphCluster(this, taskRun, parentValues, RelationType.DYNAMIC);
 
-        GraphUtils.parallel(
-            subGraph,
-            this.getTasks(),
-            this.getErrors(),
-            taskRun,
-            execution
-        );
+        if (concurrencyLimit == 1) {
+            GraphUtils.sequential(
+                subGraph,
+                this.getTasks(),
+                this.getErrors(),
+                taskRun,
+                execution
+            );
+        } else {
+            GraphUtils.parallel(
+                subGraph,
+                this.getTasks(),
+                this.getErrors(),
+                taskRun,
+                execution
+            );
+        }
 
         return subGraph;
     }