update dsl sample, make it simpler, more domain specific

Signed-off-by: Tihomir Surdilovic <[email protected]>

README.md

@@ -89,7 +89,7 @@ See the README.md file in each main sample directory for cut/paste Gradle comman
 
 - [**Money Batch**](/core/src/main/java/io/temporal/samples/moneybatch): Demonstrates a situation where a single deposit should be initiated for multiple withdrawals. For example, a seller might want to be paid once per fixed number of transactions. This sample can be easily extended to perform a payment based on more complex criteria, such as at a specific time or an accumulated amount. The sample also demonstrates how to Signal the Workflow when it executes (*Signal with start*). If the Workflow is already executing, it just receives the Signal. If it is not executing, then the Workflow executes first, and then the Signal is delivered to it. *Signal with start* is a "lazy" way to execute Workflows when Signaling them.
 
-- [**Customer Application Approval DSL**](/core/src/main/java/io/temporal/samples/dsl): Demonstrates execution of a customer application approval workflow defined in a DSL (like JSON or YAML)
+- [**DSL (JSON)**](/core/src/main/java/io/temporal/samples/dsl): Demonstrates using domain specific language (DSL) defined in JSON to specify sequence of steps to be performed in our workflow.
 
 - [**Polling Services**](/core/src/main/java/io/temporal/samples/polling): Recommended implementation of an activity that needs to periodically poll an external resource waiting its successful completion
 

core/build.gradle

@@ -27,10 +27,6 @@ dependencies {
     implementation group: 'io.cloudevents', name: 'cloudevents-core', version: '3.0.0'
     implementation group: 'io.cloudevents', name: 'cloudevents-api', version: '3.0.0'
     implementation group: 'io.cloudevents', name: 'cloudevents-json-jackson', version: '3.0.0'
-    implementation group: 'io.serverlessworkflow', name: 'serverlessworkflow-api', version: '4.0.5.Final'
-    implementation group: 'io.serverlessworkflow', name: 'serverlessworkflow-validation', version: '4.0.5.Final'
-    implementation group: 'io.serverlessworkflow', name: 'serverlessworkflow-spi', version: '4.0.5.Final'
-    implementation group: 'io.serverlessworkflow', name: 'serverlessworkflow-util', version: '4.0.5.Final'
     implementation group: 'net.thisptr', name: 'jackson-jq', version: '1.0.0-preview.20240207'
 
     // we don't update it to 2.1.0 because 2.1.0 requires Java 11

core/src/main/java/io/temporal/samples/dsl/DslActivities.java

@@ -20,18 +20,14 @@
 package io.temporal.samples.dsl;
 
 import io.temporal.activity.ActivityInterface;
-import io.temporal.samples.dsl.model.ActResult;
-import io.temporal.samples.dsl.model.Customer;
 
 @ActivityInterface
 public interface DslActivities {
-  ActResult checkCustomerInfo(Customer customer);
+  String one();
 
-  ActResult approveApplication(Customer customer);
+  String two();
 
-  ActResult rejectApplication(Customer customer);
+  String three();
 
-  ActResult updateApplicationInfo(Customer customer);
-
-  ActResult invokeBankingService(Customer customer);
+  String four();
 }

core/src/main/java/io/temporal/samples/dsl/DslActivitiesImpl.java

@@ -19,53 +19,38 @@
 
 package io.temporal.samples.dsl;
 
-import io.temporal.activity.Activity;
-import io.temporal.samples.dsl.model.ActResult;
-import io.temporal.samples.dsl.model.Customer;
+import java.util.concurrent.TimeUnit;
 
 public class DslActivitiesImpl implements DslActivities {
   @Override
-  public ActResult checkCustomerInfo(Customer customer) {
-    try {
-      return new ActResult(Activity.getExecutionContext().getInfo().getActivityType(), "invoked");
-    } catch (Exception e) {
-      return null;
-    }
+  public String one() {
+    sleep(1);
+    return "Activity one done...";
   }
 
   @Override
-  public ActResult updateApplicationInfo(Customer customer) {
-    try {
-      return new ActResult(Activity.getExecutionContext().getInfo().getActivityType(), "invoked");
-    } catch (Exception e) {
-      return null;
-    }
+  public String two() {
+    sleep(1);
+    return "Activity two done...";
   }
 
   @Override
-  public ActResult approveApplication(Customer customer) {
-    try {
-      return new ActResult("decision", "APPROVED");
-    } catch (Exception e) {
-      return null;
-    }
+  public String three() {
+    sleep(1);
+    return "Activity three done...";
   }
 
   @Override
-  public ActResult rejectApplication(Customer customer) {
-    try {
-      return new ActResult("decision-" + customer.getName(), "DENIED");
-    } catch (Exception e) {
-      return null;
-    }
+  public String four() {
+    sleep(1);
+    return "Activity four done...";
   }
 
-  @Override
-  public ActResult invokeBankingService(Customer customer) {
+  private void sleep(int seconds) {
     try {
-      return new ActResult(Activity.getExecutionContext().getInfo().getActivityType(), "invoked");
-    } catch (Exception e) {
-      return null;
+      Thread.sleep(TimeUnit.SECONDS.toMillis(seconds));
+    } catch (InterruptedException ee) {
+      // Empty
     }
   }
 }

core/src/main/java/io/temporal/samples/dsl/model/ActResult.java → core/src/main/java/io/temporal/samples/dsl/DslWorkflow.java

@@ -17,32 +17,14 @@
  *  permissions and limitations under the License.
  */
 
-package io.temporal.samples.dsl.model;
+package io.temporal.samples.dsl;
 
-public class ActResult {
-  private String type;
-  private String result;
+import io.temporal.samples.dsl.model.Flow;
+import io.temporal.workflow.WorkflowInterface;
+import io.temporal.workflow.WorkflowMethod;
 
-  public ActResult() {}
-
-  public ActResult(String type, String result) {
-    this.type = type;
-    this.result = result;
-  }
-
-  public String getResult() {
-    return result;
-  }
-
-  public void setResult(String result) {
-    this.result = result;
-  }
-
-  public String getType() {
-    return type;
-  }
-
-  public void setType(String type) {
-    this.type = type;
-  }
+@WorkflowInterface
+public interface DslWorkflow {
+  @WorkflowMethod
+  String run(Flow flow, String input);
 }

core/src/main/java/io/temporal/samples/dsl/DslWorkflowImpl.java

@@ -0,0 +1,68 @@
+/*
+ *  Copyright (c) 2020 Temporal Technologies, Inc. All Rights Reserved
+ *
+ *  Copyright 2012-2016 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ *
+ *  Modifications copyright (C) 2017 Uber Technologies, Inc.
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License"). You may not
+ *  use this file except in compliance with the License. A copy of the License is
+ *  located at
+ *
+ *  http://aws.amazon.com/apache2.0
+ *
+ *  or in the "license" file accompanying this file. This file 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.temporal.samples.dsl;
+
+import io.temporal.activity.ActivityOptions;
+import io.temporal.common.RetryOptions;
+import io.temporal.failure.ActivityFailure;
+import io.temporal.failure.ApplicationFailure;
+import io.temporal.samples.dsl.model.Flow;
+import io.temporal.samples.dsl.model.FlowAction;
+import io.temporal.workflow.ActivityStub;
+import io.temporal.workflow.Workflow;
+import java.time.Duration;
+import java.util.ArrayList;
+import java.util.List;
+
+public class DslWorkflowImpl implements DslWorkflow {
+  @Override
+  public String run(Flow flow, String input) {
+    if (flow == null || flow.getActions().isEmpty()) {
+      throw ApplicationFailure.newFailure(
+          "Flow is null or does not have any actions", "illegal flow");
+    }
+
+    try {
+      return runActions(flow, input);
+    } catch (ActivityFailure e) {
+      throw ApplicationFailure.newFailure(
+          "failing execution after compensation initiated", e.getCause().getClass().getName());
+    }
+  }
+
+  private String runActions(Flow flow, String input) {
+    List<String> results = new ArrayList<>();
+    for (FlowAction action : flow.getActions()) {
+      // build activity options based on flow action input
+      ActivityOptions.Builder activityOptionsBuilder = ActivityOptions.newBuilder();
+      activityOptionsBuilder.setStartToCloseTimeout(
+          Duration.ofSeconds(action.getStartToCloseSec()));
+      if (action.getRetries() > 0) {
+        activityOptionsBuilder.setRetryOptions(
+            RetryOptions.newBuilder().setMaximumAttempts(action.getRetries()).build());
+      }
+      // create untyped activity stub and run activity based on flow action
+      ActivityStub activityStub = Workflow.newUntypedActivityStub(activityOptionsBuilder.build());
+
+      results.add(activityStub.execute(action.getAction(), String.class, input));
+    }
+    return String.join(",", results);
+  }
+}