Introduce Fluent Agent DSL (depends on LangChain4j SNAPSHOT)

.github/workflows/maven-verify.yml

@@ -10,6 +10,7 @@ on:
   pull_request:
     branches:
       - main
+
 jobs:
   build:
     runs-on: ubuntu-latest
@@ -25,8 +26,10 @@ jobs:
 
       - name: Verify with Maven
         run: |
-          mvn -B -f pom.xml clean install verify
+          mvn -B -f pom.xml clean install verify \
+            -pl ",!fluent/agentic" \
+            -am
 
       - name: Verify Examples with Maven
         run: |
-          mvn -B -f examples/pom.xml clean install verify
+          mvn -B -f examples/pom.xml clean install verify

fluent/agentic/pom.xml

@@ -0,0 +1,65 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0"
+         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+    <modelVersion>4.0.0</modelVersion>
+    <parent>
+        <groupId>io.serverlessworkflow</groupId>
+        <artifactId>serverlessworkflow-fluent</artifactId>
+        <version>8.0.0-SNAPSHOT</version>
+    </parent>
+
+    <name>Serverless Workflow :: Fluent :: Agentic</name>
+    <artifactId>serverlessworkflow-fluent-agentic</artifactId>
+
+    <properties>
+        <maven.compiler.source>17</maven.compiler.source>
+        <maven.compiler.target>17</maven.compiler.target>
+        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
+
+        <version.dev.langchain4j>1.2.0-beta8-SNAPSHOT</version.dev.langchain4j>
+    </properties>
+
+    <dependencies>
+        <dependency>
+            <groupId>io.serverlessworkflow</groupId>
+            <artifactId>serverlessworkflow-experimental-types</artifactId>
+        </dependency>
+        <dependency>
+            <groupId>io.serverlessworkflow</groupId>
+            <artifactId>serverlessworkflow-fluent-func</artifactId>
+        </dependency>
+        <dependency>
+            <groupId>dev.langchain4j</groupId>
+            <artifactId>langchain4j-agentic</artifactId>
+            <version>${version.dev.langchain4j}</version>
+        </dependency>
+        <dependency>
+            <groupId>org.slf4j</groupId>
+            <artifactId>slf4j-simple</artifactId>
+            <scope>test</scope>
+        </dependency>
+
+        <dependency>
+            <groupId>org.junit.jupiter</groupId>
+            <artifactId>junit-jupiter-api</artifactId>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.mockito</groupId>
+            <artifactId>mockito-core</artifactId>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.assertj</groupId>
+            <artifactId>assertj-core</artifactId>
+        </dependency>
+        <dependency>
+            <groupId>dev.langchain4j</groupId>
+            <artifactId>langchain4j-ollama</artifactId>
+            <scope>test</scope>
+            <version>1.2.0-SNAPSHOT</version>
+        </dependency>
+    </dependencies>
+
+</project>

fluent/agentic/src/main/java/io/serverlessworkflow/fluent/agentic/AgentAdapters.java

@@ -0,0 +1,43 @@
+/*
+ * 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.fluent.agentic;
+
+import static dev.langchain4j.agentic.internal.AgentExecutor.agentsToExecutors;
+
+import dev.langchain4j.agentic.Cognisphere;
+import dev.langchain4j.agentic.internal.AgentExecutor;
+import dev.langchain4j.agentic.internal.AgentInstance;
+import io.serverlessworkflow.impl.expressions.LoopPredicateIndex;
+import java.util.List;
+import java.util.function.Function;
+import java.util.function.Predicate;
+import java.util.stream.Stream;
+
+public final class AgentAdapters {
+  private AgentAdapters() {}
+
+  public static List<AgentExecutor> toExecutors(Object... agents) {
+    return agentsToExecutors(Stream.of(agents).map(AgentInstance.class::cast).toList());
+  }
+
+  public static Function<Cognisphere, Object> toFunction(AgentExecutor exec) {
+    return exec::invoke;
+  }
+
+  public static LoopPredicateIndex<Object, Object> toWhile(Predicate<Cognisphere> exit) {
+    return (model, item, idx) -> !exit.test((Cognisphere) model);
+  }
+}

fluent/agentic/src/main/java/io/serverlessworkflow/fluent/agentic/AgentDoTaskBuilder.java

@@ -0,0 +1,108 @@
+/*
+ * 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.fluent.agentic;
+
+import io.serverlessworkflow.fluent.agentic.spi.AgentDoFluent;
+import io.serverlessworkflow.fluent.func.FuncCallTaskBuilder;
+import io.serverlessworkflow.fluent.func.FuncEmitTaskBuilder;
+import io.serverlessworkflow.fluent.func.FuncForTaskBuilder;
+import io.serverlessworkflow.fluent.func.FuncForkTaskBuilder;
+import io.serverlessworkflow.fluent.func.FuncSetTaskBuilder;
+import io.serverlessworkflow.fluent.func.FuncSwitchTaskBuilder;
+import io.serverlessworkflow.fluent.func.spi.ConditionalTaskBuilder;
+import io.serverlessworkflow.fluent.spec.BaseDoTaskBuilder;
+import java.util.function.Consumer;
+
+public class AgentDoTaskBuilder
+    extends BaseDoTaskBuilder<AgentDoTaskBuilder, AgentTaskItemListBuilder>
+    implements ConditionalTaskBuilder<AgentDoTaskBuilder>, AgentDoFluent<AgentDoTaskBuilder> {
+
+  public AgentDoTaskBuilder() {
+    super(new AgentTaskItemListBuilder());
+  }
+
+  @Override
+  protected AgentDoTaskBuilder self() {
+    return this;
+  }
+
+  @Override
+  public AgentDoTaskBuilder agent(String name, Object agent) {
+    this.listBuilder().agent(name, agent);
+    return self();
+  }
+
+  @Override
+  public AgentDoTaskBuilder sequence(String name, Object... agents) {
+    this.listBuilder().sequence(name, agents);
+    return self();
+  }
+
+  @Override
+  public AgentDoTaskBuilder loop(String name, Consumer<LoopAgentsBuilder> builder) {
+    this.listBuilder().loop(name, builder);
+    return self();
+  }
+
+  @Override
+  public AgentDoTaskBuilder parallel(String name, Object... agents) {
+    this.listBuilder().parallel(name, agents);
+    return self();
+  }
+
+  @Override
+  public AgentDoTaskBuilder callFn(String name, Consumer<FuncCallTaskBuilder> cfg) {
+    this.listBuilder().callFn(name, cfg);
+    return self();
+  }
+
+  @Override
+  public AgentDoTaskBuilder emit(String name, Consumer<FuncEmitTaskBuilder> itemsConfigurer) {
+    this.listBuilder().emit(name, itemsConfigurer);
+    return self();
+  }
+
+  @Override
+  public AgentDoTaskBuilder forEach(String name, Consumer<FuncForTaskBuilder> itemsConfigurer) {
+    this.listBuilder().forEach(name, itemsConfigurer);
+    return self();
+  }
+
+  @Override
+  public AgentDoTaskBuilder fork(String name, Consumer<FuncForkTaskBuilder> itemsConfigurer) {
+    this.listBuilder().fork(name, itemsConfigurer);
+    return self();
+  }
+
+  @Override
+  public AgentDoTaskBuilder set(String name, Consumer<FuncSetTaskBuilder> itemsConfigurer) {
+    this.listBuilder().set(name, itemsConfigurer);
+    return self();
+  }
+
+  @Override
+  public AgentDoTaskBuilder set(String name, String expr) {
+    this.listBuilder().set(name, expr);
+    return self();
+  }
+
+  @Override
+  public AgentDoTaskBuilder switchCase(
+      String name, Consumer<FuncSwitchTaskBuilder> itemsConfigurer) {
+    this.listBuilder().switchCase(name, itemsConfigurer);
+    return self();
+  }
+}

fluent/agentic/src/main/java/io/serverlessworkflow/fluent/agentic/AgentTaskItemListBuilder.java

@@ -0,0 +1,134 @@
+/*
+ * 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.fluent.agentic;
+
+import dev.langchain4j.agentic.internal.AgentExecutor;
+import io.serverlessworkflow.api.types.Task;
+import io.serverlessworkflow.api.types.TaskItem;
+import io.serverlessworkflow.fluent.agentic.spi.AgentDoFluent;
+import io.serverlessworkflow.fluent.func.FuncCallTaskBuilder;
+import io.serverlessworkflow.fluent.func.FuncEmitTaskBuilder;
+import io.serverlessworkflow.fluent.func.FuncForTaskBuilder;
+import io.serverlessworkflow.fluent.func.FuncForkTaskBuilder;
+import io.serverlessworkflow.fluent.func.FuncSetTaskBuilder;
+import io.serverlessworkflow.fluent.func.FuncSwitchTaskBuilder;
+import io.serverlessworkflow.fluent.func.FuncTaskItemListBuilder;
+import io.serverlessworkflow.fluent.spec.BaseTaskItemListBuilder;
+import java.util.List;
+import java.util.function.Consumer;
+
+public class AgentTaskItemListBuilder extends BaseTaskItemListBuilder<AgentTaskItemListBuilder>
+    implements AgentDoFluent<AgentTaskItemListBuilder> {
+
+  private final FuncTaskItemListBuilder delegate;
+
+  public AgentTaskItemListBuilder() {
+    super();
+    this.delegate = new FuncTaskItemListBuilder(super.mutableList());
+  }
+
+  @Override
+  protected AgentTaskItemListBuilder self() {
+    return this;
+  }
+
+  @Override
+  protected AgentTaskItemListBuilder newItemListBuilder() {
+    return new AgentTaskItemListBuilder();
+  }
+
+  @Override
+  public AgentTaskItemListBuilder agent(String name, Object agent) {
+    AgentAdapters.toExecutors(agent)
+        .forEach(
+            exec -> this.delegate.callFn(name, fn -> fn.function(AgentAdapters.toFunction(exec))));
+    return self();
+  }
+
+  @Override
+  public AgentTaskItemListBuilder sequence(String name, Object... agents) {
+    for (int i = 0; i < agents.length; i++) {
+      agent(name + "-" + i, agents[i]);
+    }
+    return self();
+  }
+
+  @Override
+  public AgentTaskItemListBuilder loop(String name, Consumer<LoopAgentsBuilder> consumer) {
+    final LoopAgentsBuilder builder = new LoopAgentsBuilder();
+    consumer.accept(builder);
+    this.addTaskItem(new TaskItem(name, new Task().withForTask(builder.build())));
+    return self();
+  }
+
+  @Override
+  public AgentTaskItemListBuilder parallel(String name, Object... agents) {
+    this.delegate.fork(
+        name,
+        fork -> {
+          List<AgentExecutor> execs = AgentAdapters.toExecutors(agents);
+          for (int i = 0; i < execs.size(); i++) {
+            AgentExecutor ex = execs.get(i);
+            fork.branch("branch-" + i + "-" + name, AgentAdapters.toFunction(ex));
+          }
+        });
+    return self();
+  }
+
+  @Override
+  public AgentTaskItemListBuilder callFn(String name, Consumer<FuncCallTaskBuilder> cfg) {
+    this.delegate.callFn(name, cfg);
+    return self();
+  }
+
+  @Override
+  public AgentTaskItemListBuilder emit(String name, Consumer<FuncEmitTaskBuilder> itemsConfigurer) {
+    this.delegate.emit(name, itemsConfigurer);
+    return self();
+  }
+
+  @Override
+  public AgentTaskItemListBuilder forEach(
+      String name, Consumer<FuncForTaskBuilder> itemsConfigurer) {
+    this.delegate.forEach(name, itemsConfigurer);
+    return self();
+  }
+
+  @Override
+  public AgentTaskItemListBuilder fork(String name, Consumer<FuncForkTaskBuilder> itemsConfigurer) {
+    this.delegate.fork(name, itemsConfigurer);
+    return self();
+  }
+
+  @Override
+  public AgentTaskItemListBuilder set(String name, Consumer<FuncSetTaskBuilder> itemsConfigurer) {
+    this.delegate.set(name, itemsConfigurer);
+    return self();
+  }
+
+  @Override
+  public AgentTaskItemListBuilder set(String name, String expr) {
+    this.delegate.set(name, expr);
+    return self();
+  }
+
+  @Override
+  public AgentTaskItemListBuilder switchCase(
+      String name, Consumer<FuncSwitchTaskBuilder> itemsConfigurer) {
+    this.delegate.switchCase(name, itemsConfigurer);
+    return self();
+  }
+}