[Fix #1198] Adding error variable

Signed-off-by: fjtirado <ftirados@redhat.com>

Author: fjtirado

impl/core/src/main/java/io/serverlessworkflow/impl/executors/TryExecutor.java

@@ -52,6 +52,7 @@ public class TryExecutor extends RegularTaskExecutor<TryTask> {
   private final TaskExecutor<?> taskExecutor;
   private final Optional<TaskExecutor<?>> catchTaskExecutor;
   private final Optional<RetryExecutor> retryIntervalExecutor;
+  private final String errorVariable;
 
   public static class TryExecutorBuilder extends RegularTaskExecutorBuilder<TryTask> {
 
@@ -61,6 +62,7 @@ public static class TryExecutorBuilder extends RegularTaskExecutorBuilder<TryTas
     private final TaskExecutor<?> taskExecutor;
     private final Optional<TaskExecutor<?>> catchTaskExecutor;
     private final Optional<RetryExecutor> retryIntervalExecutor;
+    private String errorVariable;
 
     protected TryExecutorBuilder(
         WorkflowMutablePosition position, TryTask task, WorkflowDefinition definition) {
@@ -73,8 +75,8 @@ protected TryExecutorBuilder(
           TaskExecutorHelper.createExecutorList(position, task.getTry(), definition);
       TryTaskCatch catchTask = task.getCatch();
       if (catchTask != null) {
+        this.errorVariable = catchTask.getAs();
         List<TaskItem> catchTaskDo = catchTask.getDo();
-
         this.catchTaskExecutor =
             catchTaskDo != null && !catchTaskDo.isEmpty()
                 ? Optional.of(
@@ -144,6 +146,7 @@ protected TryExecutor(TryExecutorBuilder builder) {
     this.taskExecutor = builder.taskExecutor;
     this.catchTaskExecutor = builder.catchTaskExecutor;
     this.retryIntervalExecutor = builder.retryIntervalExecutor;
+    this.errorVariable = builder.errorVariable;
   }
 
   @Override
@@ -171,6 +174,9 @@ private CompletableFuture<WorkflowModel> handleException(
       if (errorFilter.map(f -> f.test(exception.getWorkflowError())).orElse(true)
           && WorkflowUtils.whenExceptTest(
               whenFilter, exceptFilter, workflow, taskContext, taskContext.rawOutput())) {
+        if (errorVariable != null) {
+          taskContext.variables().put(errorVariable, exception.getWorkflowError());
+        }
         if (catchTaskExecutor.isPresent()) {
           completable =
               completable.thenCompose(

impl/test/src/test/java/io/serverlessworkflow/impl/test/RetryTimeoutTest.java

@@ -137,4 +137,18 @@ void testDoesNotMatch(String path) {
                     .join())
         .hasCauseInstanceOf(WorkflowException.class);
   }
+
+  @Test
+  void testErrorVariable() throws IOException {
+    assertThat(
+            app.workflowDefinition(
+                    readWorkflowFromClasspath("workflows-samples/try-catch-error-variable.yaml"))
+                .instance(Map.of())
+                .start()
+                .join()
+                .asMap()
+                .map(m -> m.get("errorMessage"))
+                .orElseThrow())
+        .isEqualTo("Javierito was here!");
+  }
 }

impl/test/src/test/resources/workflows-samples/try-catch-error-variable.yaml

@@ -0,0 +1,20 @@
+document:
+  dsl: '1.0.0'
+  namespace: test
+  name: try-catch-error-variable
+  version: '0.1.0'
+do:
+  - attemptTask:
+      try:
+          - failingTask:
+                  raise:
+                      error:
+                          type: https://example.com/errors/transient
+                          detail: Javierito was here!
+                          status: 503
+      catch:
+          as: caughtError
+          do:
+              - handleError:
+                      set:
+                          errorMessage: ${$caughtError.details}