[Fix #899] Add RunTask infrastructure

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

@@ -27,6 +27,7 @@
 import io.serverlessworkflow.impl.executors.ForkExecutor.ForkExecutorBuilder;
 import io.serverlessworkflow.impl.executors.ListenExecutor.ListenExecutorBuilder;
 import io.serverlessworkflow.impl.executors.RaiseExecutor.RaiseExecutorBuilder;
+import io.serverlessworkflow.impl.executors.RunTaskExecutor.RunTaskExecutorBuilder;
 import io.serverlessworkflow.impl.executors.SetExecutor.SetExecutorBuilder;
 import io.serverlessworkflow.impl.executors.SwitchExecutor.SwitchExecutorBuilder;
 import io.serverlessworkflow.impl.executors.TryExecutor.TryExecutorBuilder;
@@ -76,6 +77,8 @@ public TaskExecutorBuilder<? extends TaskBase> getTaskExecutor(
       return new ListenExecutorBuilder(position, task.getListenTask(), definition);
     } else if (task.getEmitTask() != null) {
       return new EmitExecutorBuilder(position, task.getEmitTask(), definition);
+    } else if (task.getRunTask() != null) {
+      return new RunTaskExecutorBuilder(position, task.getRunTask(), definition);
     }
     throw new UnsupportedOperationException(task.get().getClass().getName() + " not supported yet");
   }

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

@@ -0,0 +1,71 @@
+/*
+ * Copyright 2020-Present The Serverless Workflow Specification Authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package io.serverlessworkflow.impl.executors;
+
+import io.serverlessworkflow.api.types.RunTask;
+import io.serverlessworkflow.api.types.RunTaskConfiguration;
+import io.serverlessworkflow.impl.TaskContext;
+import io.serverlessworkflow.impl.WorkflowContext;
+import io.serverlessworkflow.impl.WorkflowDefinition;
+import io.serverlessworkflow.impl.WorkflowModel;
+import io.serverlessworkflow.impl.WorkflowMutablePosition;
+import java.util.ServiceLoader;
+import java.util.ServiceLoader.Provider;
+import java.util.concurrent.CompletableFuture;
+
+public class RunTaskExecutor<T extends RunTaskConfiguration> extends RegularTaskExecutor<RunTask> {
+
+  private final RunnableTask<T> runnable;
+
+  private static final ServiceLoader<RunnableTask> runnables =
+      ServiceLoader.load(RunnableTask.class);
+
+  public static class RunTaskExecutorBuilder extends RegularTaskExecutorBuilder<RunTask> {
+    private RunnableTask runnable;
+
+    protected RunTaskExecutorBuilder(
+        WorkflowMutablePosition position, RunTask task, WorkflowDefinition definition) {
+      super(position, task, definition);
+      RunTaskConfiguration config = task.getRun().get();
+      this.runnable =
+          runnables.stream()
+              .map(Provider::get)
+              .filter(r -> r.accept(config.getClass()))
+              .findFirst()
+              .orElseThrow(
+                  () ->
+                      new UnsupportedOperationException(
+                          "No runnable found for operation " + config.getClass()));
+      runnable.init(config, definition);
+    }
+
+    @Override
+    public RunTaskExecutor buildInstance() {
+      return new RunTaskExecutor(this);
+    }
+  }
+
+  protected RunTaskExecutor(RunTaskExecutorBuilder builder) {
+    super(builder);
+    this.runnable = builder.runnable;
+  }
+
+  @Override
+  protected CompletableFuture<WorkflowModel> internalExecute(
+      WorkflowContext workflow, TaskContext taskContext) {
+    return runnable.apply(workflow, taskContext, taskContext.input());
+  }
+}

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

@@ -0,0 +1,60 @@
+/*
+ * Copyright 2020-Present The Serverless Workflow Specification Authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package io.serverlessworkflow.impl.executors;
+
+import io.serverlessworkflow.api.types.RunTaskConfiguration;
+import io.serverlessworkflow.api.types.RunWorkflow;
+import io.serverlessworkflow.api.types.SubflowConfiguration;
+import io.serverlessworkflow.impl.TaskContext;
+import io.serverlessworkflow.impl.WorkflowContext;
+import io.serverlessworkflow.impl.WorkflowDefinition;
+import io.serverlessworkflow.impl.WorkflowDefinitionId;
+import io.serverlessworkflow.impl.WorkflowModel;
+import java.util.Map;
+import java.util.concurrent.CompletableFuture;
+
+public class RunWorkflowExecutor implements RunnableTask<RunWorkflow> {
+
+  private WorkflowDefinitionId workflowDefinitionId;
+  private Map<String, Object> additionalParameters;
+
+  public void init(RunWorkflow taskConfiguration, WorkflowDefinition definition) {
+    SubflowConfiguration workflowConfig = taskConfiguration.getWorkflow();
+    this.workflowDefinitionId =
+        new WorkflowDefinitionId(
+            workflowConfig.getNamespace(), workflowConfig.getName(), workflowConfig.getVersion());
+    this.additionalParameters = workflowConfig.getInput().getAdditionalProperties();
+  }
+
+  @Override
+  public CompletableFuture<WorkflowModel> apply(
+      WorkflowContext workflowContext, TaskContext taskContext, WorkflowModel input) {
+    WorkflowDefinition definition =
+        workflowContext.definition().application().workflowDefinitions().get(workflowDefinitionId);
+    if (definition != null) {
+      //  TODO add additional parameters
+      return definition.instance(input).start();
+    } else {
+      throw new IllegalArgumentException(
+          "Workflow definition for " + workflowDefinitionId + " has not been found");
+    }
+  }
+
+  @Override
+  public boolean accept(Class<? extends RunTaskConfiguration> clazz) {
+    return RunWorkflow.class.equals(clazz);
+  }
+}

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

@@ -0,0 +1,32 @@
+/*
+ * Copyright 2020-Present The Serverless Workflow Specification Authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package io.serverlessworkflow.impl.executors;
+
+import io.serverlessworkflow.api.types.RunTaskConfiguration;
+import io.serverlessworkflow.impl.TaskContext;
+import io.serverlessworkflow.impl.WorkflowContext;
+import io.serverlessworkflow.impl.WorkflowDefinition;
+import io.serverlessworkflow.impl.WorkflowModel;
+import java.util.concurrent.CompletableFuture;
+
+public interface RunnableTask<T extends RunTaskConfiguration> {
+  default void init(T taskConfiguration, WorkflowDefinition definition) {}
+
+  CompletableFuture<WorkflowModel> apply(
+      WorkflowContext workflowContext, TaskContext taskContext, WorkflowModel input);
+
+  boolean accept(Class<? extends RunTaskConfiguration> clazz);
+}

impl/core/src/main/resources/META-INF/services/io.serverlessworkflow.impl.executors.RunnableTask

@@ -0,0 +1 @@
+io.serverlessworkflow.impl.executors.RunWorkflowExecutor