SwitchYard provides an implementation-agnostic API is available which allows you to programmatically interact with Human Tasks.  The API provides mechanisms to:

• Start and stop a Task Server.

• Connect a Task Client to a Task Server.

• Use the Task Client to:

  • Get assigned Tasks.

  • Claim Tasks.

  • Start Tasks.

  • Get/Set Task Content.

  • Complete Tasks.

• Inspect Tasks for their id, name, status and parent process instance id.

The API is a very thin wrapper around jBPM, and doesn't cover everything you can do with jBPM.  As people require more functionality to be exposed, we will consider adding those hooks.

The purpose behind providing a SwitchYard-specific Task API is two-fold:

1. Make it easy for web application developers to access and manage tasks in the BPM runtime.  The point here is that people are going to create their own web apps that interact with BPM tasks.

2. Provide an abstraction over the implementation.  Using this API developers only have to worry about SwitchYard interfaces rather than depending upon another library. It also allows us to integrate with another BPM runtime in the future if we so choose (although the chances of that are slim for the foreseeable future).

For all examples below, please assume the following import:

import org.switchyard.component.bpm.task.*;

TaskServer server = TaskService.instance().newTaskServer();
server.setHost("localhost").setPort(9123).start();
// task clients can connect
server.stop();

TaskClient client = TaskService.instance().newTaskClient();
client.setHost("localhost").setPort(9123).connect();
// work with the client
client.disconnect();

TaskClient client = // see above
String userId = "david";
List<String> groupIds = Arrays.asList(new String[]{"users"});
List<Task> tasks = client.getTasksAssignedAsPotentialOwner(userId, groupIds);
for (Task task : tasks) {
    if (TaskStatus.COMPLETED.equals(task.getStatus())) {
        continue;
    }
    Long taskId = task.getId();
    client.claim(taskId, userId, groupIds);
    client.start(taskId, userId);
    client.complete(taskId, userId, null);
}

TaskClient client = // see above
String userId = // see above
Task task = // see above
TaskContent content = client.getTaskContent(task.getTaskContentId());
Map<String, Object> data = content.getVariableMap();
MyAppObject mao = (MyAppObject)data.get("myAppVariable");
// use or mutate mao
client.complete(task.getId(), userId, content);