List by user

New to Akka? Start here:

Use the Build your first agent guide to get a simple agentic service running locally and interact with it.

Overview

We can retrieve the result of an individual user query directly from the workflow, using the session id that corresponds to the workflow id. It would be nice to list the historical result by user id.

In this part of the guide you will:

Add a view to be able to query all activity suggestions for a user
Add a method in the endpoint to use the view

Prerequisites

Java 21, we recommend Eclipse Adoptium
Apache Maven version 3.9 or later
curl command-line tool
OpenAI API key

Add a view

Add a new file ActivityView.java to src/main/java/com/example/application/

ActivityView.java

import akka.javasdk.annotations.ComponentId;
import akka.javasdk.annotations.Consume;
import akka.javasdk.annotations.DeleteHandler;
import akka.javasdk.annotations.Query;
import akka.javasdk.view.TableUpdater;
import akka.javasdk.view.View;
import java.util.List;

@ComponentId("activity-view")
public class ActivityView extends View {

  public record ActivityEntries(List<ActivityEntry> entries) {}

  public record ActivityEntry(String userId, String userQuestion, String finalAnswer) {}

  @Query("SELECT * AS entries FROM activities WHERE userId = :userId") (1)
  public QueryEffect<ActivityEntries> getActivities(String userId) {
    return queryResult();
  }

  @Consume.FromWorkflow(AgentTeamWorkflow.class) (2)
  public static class Updater extends TableUpdater<ActivityEntry> {

    public Effect<ActivityEntry> onStateChange(AgentTeamWorkflow.State state) {
      return effects()
        .updateRow(new ActivityEntry(state.userId(), state.userQuery(), state.finalAnswer()));
    }

    @DeleteHandler
    public Effect<ActivityEntry> onDelete() {
      return effects().deleteRow();
    }
  }
}

1	The query selects all rows for a given user id.
2	The view is updated from the state changes of the workflow.

Expose in the endpoint

Add a new method that asks the view for a given user id.

public record ActivitiesList(List<Suggestion> suggestions) {
  static ActivitiesList fromView(ActivityView.ActivityEntries entries) {
    return new ActivitiesList(
      entries.entries().stream().map(Suggestion::fromView).toList()
    );
  }
}

public record Suggestion(String userQuestion, String answer) {
  static Suggestion fromView(ActivityView.ActivityEntry entry) {
    return new Suggestion(entry.userQuestion(), entry.finalAnswer());
  }
}

@Get("/activities/{userId}")
public ActivitiesList listActivities(String userId) {
  var viewResult = componentClient
    .forView()
    .method(ActivityView::getActivities)
    .invoke(userId);

  return ActivitiesList.fromView(viewResult);
}

Running the service

Start your service locally:

mvn compile exec:java

Ask for activities.

curl -i -XPOST --location "http://localhost:9000/activities/alice" \
  --header "Content-Type: application/json" \
  --data '{"message": "I am in Madrid. What should I do? Beware of the weather."}'

Retrieve the suggested activities with the new list method:

curl -i -XGET --location "http://localhost:9000/activities/alice"

Make another request for activities:

curl -i -XPOST --location "http://localhost:9000/activities/alice" \
  --header "Content-Type: application/json" \
  --data '{"message": "I am in Stockholm. What should I do? Take the weather into account."}'

The list should include suggested activities for both Madrid and Stockholm:

curl -i -XGET --location "http://localhost:9000/activities/alice"

If you have jq installed you can format the json response with:

curl http://localhost:9000/activities/alice | jq

Next steps

In a larger system with more agents, we could benefit from letting the AI model come up with a plan of which agents to use and in which order to execute. Continue with Dynamic orchestration
Learn more about the View component.