Introduce LangChain4j Agentic Workflow Implementation

experimental/agentic/src/main/java/io/serverlessworkflow/impl/expressions/agentic/AgenticModel.java

@@ -16,20 +16,15 @@
 package io.serverlessworkflow.impl.expressions.agentic;
 
 import dev.langchain4j.agentic.cognisphere.Cognisphere;
-import dev.langchain4j.agentic.cognisphere.ResultWithCognisphere;
 import io.serverlessworkflow.impl.WorkflowModel;
 import io.serverlessworkflow.impl.expressions.func.JavaModel;
 import java.util.Collection;
-import java.util.Collections;
 import java.util.Optional;
 
 class AgenticModel extends JavaModel {
 
-  private final Cognisphere cognisphere;
-
-  AgenticModel(Object object, Cognisphere cognisphere) {
-    super(object);
-    this.cognisphere = cognisphere;
+  AgenticModel(Cognisphere cognisphere) {
+    super(cognisphere);
   }
 
   @Override
@@ -39,17 +34,13 @@ public void setObject(Object obj) {
 
   @Override
   public Collection<WorkflowModel> asCollection() {
-    return object instanceof Collection value
-        ? new AgenticModelCollection(value, cognisphere)
-        : Collections.emptyList();
+    throw new UnsupportedOperationException("Not supported yet.");
   }
 
   @Override
   public <T> Optional<T> as(Class<T> clazz) {
     if (Cognisphere.class.isAssignableFrom(clazz)) {
-      return Optional.of(clazz.cast(cognisphere));
-    } else if (ResultWithCognisphere.class.isAssignableFrom(clazz)) {
-      return Optional.of(clazz.cast(new ResultWithCognisphere<>(cognisphere, object)));
+      return Optional.of(clazz.cast(object));
     } else {
       return super.as(clazz);
     }

experimental/agentic/src/main/java/io/serverlessworkflow/impl/expressions/agentic/AgenticModelCollection.java

@@ -37,7 +37,7 @@ class AgenticModelCollection extends JavaModelCollection {
 
   @Override
   protected WorkflowModel nextItem(Object obj) {
-    return new AgenticModel(obj, cognisphere);
+    return new AgenticModel((Cognisphere) obj);
   }
 
   @Override

experimental/agentic/src/main/java/io/serverlessworkflow/impl/expressions/agentic/AgenticModelFactory.java

@@ -16,27 +16,17 @@
 package io.serverlessworkflow.impl.expressions.agentic;
 
 import dev.langchain4j.agentic.cognisphere.Cognisphere;
-import dev.langchain4j.agentic.cognisphere.CognisphereRegistry;
 import io.cloudevents.CloudEvent;
 import io.cloudevents.CloudEventData;
 import io.serverlessworkflow.impl.WorkflowModel;
 import io.serverlessworkflow.impl.WorkflowModelCollection;
 import io.serverlessworkflow.impl.WorkflowModelFactory;
+import io.serverlessworkflow.impl.expressions.func.JavaModel;
 import java.time.OffsetDateTime;
 import java.util.Map;
 
 class AgenticModelFactory implements WorkflowModelFactory {
 
-  private Cognisphere cognisphere = CognisphereRegistry.createEphemeralCognisphere();
-
-  private final AgenticModel TrueModel = new AgenticModel(Boolean.TRUE, cognisphere);
-  private final AgenticModel FalseModel = new AgenticModel(Boolean.FALSE, cognisphere);
-  private final AgenticModel NullModel = new AgenticModel(null, cognisphere);
-
-  public void setCognishere(Cognisphere cognisphere) {
-    this.cognisphere = cognisphere;
-  }
-
   @Override
   public WorkflowModel fromAny(WorkflowModel prev, Object obj) {
     ((AgenticModel) prev).setObject(obj);
@@ -45,57 +35,59 @@ public WorkflowModel fromAny(WorkflowModel prev, Object obj) {
 
   @Override
   public WorkflowModel combine(Map<String, WorkflowModel> workflowVariables) {
-    return new AgenticModel(workflowVariables, cognisphere);
+    throw new UnsupportedOperationException();
   }
 
   @Override
   public WorkflowModelCollection createCollection() {
-    return new AgenticModelCollection(cognisphere);
+    throw new UnsupportedOperationException();
   }
 
   @Override
   public WorkflowModel from(boolean value) {
-    return value ? TrueModel : FalseModel;
+    return new JavaModel(value);
   }
 
   @Override
   public WorkflowModel from(Number value) {
-    return new AgenticModel(value, cognisphere);
+    return new JavaModel(value);
   }
 
   @Override
   public WorkflowModel from(String value) {
-    return new AgenticModel(value, cognisphere);
+    return new JavaModel(value);
   }
 
   @Override
   public WorkflowModel from(CloudEvent ce) {
-    return new AgenticModel(ce, cognisphere);
+    return new JavaModel(ce);
   }
 
   @Override
   public WorkflowModel from(CloudEventData ce) {
-    return new AgenticModel(ce, cognisphere);
+    return new JavaModel(ce);
   }
 
   @Override
   public WorkflowModel from(OffsetDateTime value) {
-    return new AgenticModel(value, cognisphere);
+    return new JavaModel(value);
   }
 
   @Override
   public WorkflowModel from(Map<String, Object> map) {
-    cognisphere.writeStates(map);
-    return new AgenticModel(map, cognisphere);
+    return new JavaModel(map);
   }
 
   @Override
   public WorkflowModel fromNull() {
-    return NullModel;
+    return new JavaModel(null);
   }
 
   @Override
   public WorkflowModel fromOther(Object value) {
-    return new AgenticModel(value, cognisphere);
+    if (value instanceof Cognisphere) {
+      return new AgenticModel((Cognisphere) value);
+    }
+    return new JavaModel(value);
   }
 }

experimental/lambda/src/main/java/io/serverlessworkflow/impl/expressions/func/JavaModel.java

@@ -29,7 +29,7 @@ public class JavaModel implements WorkflowModel {
 
   protected Object object;
 
-  protected JavaModel(Object object) {
+  public JavaModel(Object object) {
     this.object = asJavaObject(object);
   }
 

fluent/agentic-langchain4j/pom.xml

@@ -0,0 +1,68 @@
+<?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>
+
+    <artifactId>serverlessworkflow-fluent-agentic-langchain4j</artifactId>
+    <name>Serverless Workflow :: Fluent :: Agentic LangChain4j</name>
+    <description>Agentic Workflow DSL Implementation for langchain4j-agentic</description>
+
+    <dependencies>
+        <dependency>
+            <groupId>io.serverlessworkflow</groupId>
+            <artifactId>serverlessworkflow-experimental-agentic</artifactId>
+        </dependency>
+        <dependency>
+            <groupId>io.serverlessworkflow</groupId>
+            <artifactId>serverlessworkflow-fluent-agentic</artifactId>
+        </dependency>
+        <dependency>
+            <groupId>dev.langchain4j</groupId>
+            <artifactId>langchain4j-agentic</artifactId>
+        </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>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>dev.langchain4j</groupId>
+            <artifactId>langchain4j-ollama</artifactId>
+            <scope>test</scope>
+            <version>${version.dev.langchain4j}</version>
+        </dependency>
+        <dependency>
+            <groupId>io.serverlessworkflow</groupId>
+            <artifactId>serverlessworkflow-fluent-agentic</artifactId>
+            <type>test-jar</type>
+            <scope>test</scope>
+        </dependency>
+    </dependencies>
+
+
+
+
+
+</project>

fluent/agentic-langchain4j/src/main/java/io/serverlessworkflow/fluent/agentic/langchain4j/AbstractAgentService.java

@@ -0,0 +1,87 @@
+/*
+ * 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.langchain4j;
+
+import dev.langchain4j.agentic.cognisphere.Cognisphere;
+import dev.langchain4j.agentic.internal.AgentSpecification;
+import dev.langchain4j.agentic.internal.CognisphereOwner;
+import io.serverlessworkflow.api.types.Workflow;
+import io.serverlessworkflow.fluent.agentic.AgentWorkflowBuilder;
+import io.serverlessworkflow.impl.WorkflowApplication;
+import java.lang.reflect.Proxy;
+import java.util.function.Consumer;
+import java.util.function.Function;
+
+public abstract class AbstractAgentService<T, S> implements WorkflowDefinitionBuilder {
+
+  // Workflow OutputAs
+  private static final Function<Cognisphere, Object> DEFAULT_OUTPUT_FUNCTION = cognisphere -> null;
+  // Workflow InputFrom
+  private static final Consumer<Cognisphere> DEFAULT_INPUT_FUNCTION = cognisphere -> {};
+
+  protected final WorkflowApplication.Builder workflowExecBuilder;
+  protected final AgentWorkflowBuilder workflowBuilder;
+  protected final Class<T> agentServiceClass;
+
+  protected AbstractAgentService(Class<T> agentServiceClass) {
+    this.workflowBuilder =
+        AgentWorkflowBuilder.workflow()
+            .outputAs(DEFAULT_OUTPUT_FUNCTION)
+            .input(i -> i.from(DEFAULT_INPUT_FUNCTION));
+    this.agentServiceClass = agentServiceClass;
+    this.workflowExecBuilder = WorkflowApplication.builder();
+  }
+
+  @SuppressWarnings("unchecked")
+  public T build() {
+    return (T)
+        Proxy.newProxyInstance(
+            this.agentServiceClass.getClassLoader(),
+            new Class<?>[] {agentServiceClass, AgentSpecification.class, CognisphereOwner.class},
+            new WorkflowInvocationHandler(this.workflowBuilder.build(), this.workflowExecBuilder, this.agentServiceClass));
+  }
+
+  @SuppressWarnings("unchecked")
+  public S beforeCall(Consumer<Cognisphere> beforeCall) {
+    this.workflowBuilder.inputFrom(
+        cog -> {
+          beforeCall.accept(cog);
+          return cog;
+        },
+        Cognisphere.class);
+    return (S) this;
+  }
+
+  @SuppressWarnings("unchecked")
+  public S outputName(String outputName) {
+    Function<Cognisphere, Object> outputFunction = cog -> cog.readState(outputName);
+    this.workflowBuilder.outputAs(outputFunction, Cognisphere.class);
+    this.workflowBuilder.document(
+        d -> d.metadata(m -> m.metadata(META_KEY_OUTPUTNAME, outputName)));
+    return (S) this;
+  }
+
+  @SuppressWarnings("unchecked")
+  public S output(Function<Cognisphere, Object> output) {
+    this.workflowBuilder.outputAs(output, Cognisphere.class);
+    return (S) this;
+  }
+
+  @Override
+  public Workflow getDefinition() {
+    return this.workflowBuilder.build();
+  }
+}

fluent/agentic-langchain4j/src/main/java/io/serverlessworkflow/fluent/agentic/langchain4j/ConditionalAgentServiceImpl.java

@@ -0,0 +1,67 @@
+/*
+ * 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.langchain4j;
+
+import dev.langchain4j.agentic.cognisphere.Cognisphere;
+import dev.langchain4j.agentic.internal.AgentExecutor;
+import dev.langchain4j.agentic.workflow.ConditionalAgentService;
+import java.util.Arrays;
+import java.util.List;
+import java.util.function.Predicate;
+
+public class ConditionalAgentServiceImpl<T>
+    extends AbstractAgentService<T, ConditionalAgentService<T>>
+    implements ConditionalAgentService<T> {
+
+  private ConditionalAgentServiceImpl(Class<T> agentServiceClass) {
+    super(agentServiceClass);
+  }
+
+  public static <T> ConditionalAgentService<T> builder(Class<T> agentServiceClass) {
+    return new ConditionalAgentServiceImpl<>(agentServiceClass);
+  }
+
+  @Override
+  public ConditionalAgentService<T> subAgents(Object... agents) {
+    this.workflowBuilder.tasks(t -> t.sequence(agents));
+    return this;
+  }
+
+  @Override
+  public ConditionalAgentService<T> subAgents(List<AgentExecutor> agentExecutors) {
+    return this.subAgents(agentExecutors.toArray());
+  }
+
+  @Override
+  public ConditionalAgentService<T> subAgents(Predicate<Cognisphere> condition, Object... agents) {
+    this.workflowBuilder.tasks(
+        t -> Arrays.stream(agents).forEach(agent -> t.when(condition).agent(agent)));
+    return this;
+  }
+
+  @Override
+  public ConditionalAgentService<T> subAgents(
+      Predicate<Cognisphere> condition, List<AgentExecutor> agentExecutors) {
+    return this.subAgents(condition, agentExecutors.toArray());
+  }
+
+  @Override
+  public ConditionalAgentService<T> subAgent(
+      Predicate<Cognisphere> condition, AgentExecutor agentExecutor) {
+    this.workflowBuilder.tasks(t -> t.when(condition).agent(agentExecutor));
+    return this;
+  }
+}