Chapter 2. KIE Server Java client API for KIE containers and business assets

Red Hat Process Automation Manager provides a KIE Server Java client API that enables you to connect to KIE Server using REST protocol from your Java client application. You can use the KIE Server Java client API as an alternative to the KIE Server REST API to interact with your KIE containers and business assets (such as business rules, processes, and solvers) in Red Hat Process Automation Manager without using the Business Central user interface. This API support enables you to maintain your Red Hat Process Automation Manager resources more efficiently and optimize your integration and development with Red Hat Process Automation Manager.

With the KIE Server Java client API, you can perform the following actions also supported by the KIE Server REST API:

  • Deploy or dispose KIE containers
  • Retrieve and update KIE container information
  • Return KIE Server status and basic information
  • Retrieve and update business asset information
  • Execute business assets (such as rules and processes)

KIE Server Java client API requests require the following components:

Authentication

The KIE Server Java client API requires HTTP Basic authentication for the user role kie-server. To view configured user roles for your Red Hat Process Automation Manager distribution, navigate to ~/$SERVER_HOME/standalone/configuration/application-roles.properties and ~/application-users.properties.

To add a user with the kie-server role, navigate to ~/$SERVER_HOME/bin and run the following command:

$ ./add-user.sh -a --user <USERNAME> --password <PASSWORD> --role kie-server

For more information about user roles and Red Hat Process Automation Manager installation options, see Planning a Red Hat Process Automation Manager installation.

Project dependencies

The KIE Server Java client API requires the following dependencies on the relevant classpath of your Java project:

<!-- For remote execution on KIE Server -->
<dependency>
  <groupId>org.kie.server</groupId>
  <artifactId>kie-server-client</artifactId>
  <version>${rhpam.version}</version>
</dependency>

<!-- For runtime commands -->
<dependency>
  <groupId>org.drools</groupId>
  <artifactId>drools-compiler</artifactId>
  <scope>runtime</scope>
  <version>${rhpam.version}</version>
</dependency>

<!-- For debug logging (optional) -->
<dependency>
  <groupId>ch.qos.logback</groupId>
  <artifactId>logback-classic</artifactId>
  <version>${logback.version}</version>
</dependency>

The <version> for Red Hat Process Automation Manager dependencies is the Maven artifact version for Red Hat Process Automation Manager currently used in your project (for example, 7.39.0.Final-redhat-00005).

Note

Instead of specifying a Red Hat Process Automation Manager <version> for individual dependencies, consider adding the Red Hat Business Automation bill of materials (BOM) dependency to your project pom.xml file. The Red Hat Business Automation BOM applies to both Red Hat Decision Manager and Red Hat Process Automation Manager. When you add the BOM files, the correct versions of transitive dependencies from the provided Maven repositories are included in the project.

Example BOM dependency:

<dependency>
  <groupId>com.redhat.ba</groupId>
  <artifactId>ba-platform-bom</artifactId>
  <version>7.8.0.redhat-00005</version>
  <scope>import</scope>
  <type>pom</type>
</dependency>

For more information about the Red Hat Business Automation BOM, see What is the mapping between RHPAM product and maven library version?.

Client request configuration

All Java client requests with the KIE Server Java client API must define at least the following server communication components:

  • Credentials of the kie-server user
  • KIE Server location, such as http://localhost:8080/kie-server/services/rest/server
  • Marshalling format for API requests and responses (JSON, JAXB, or XSTREAM)
  • A KieServicesConfiguration object and a KieServicesClient object, which serve as the entry point for starting the server communication using the Java client API
  • A KieServicesFactory object defining REST protocol and user access
  • Any other client services used, such as RuleServicesClient, ProcessServicesClient, or QueryServicesClient

The following are examples of basic and advanced client configurations with these components:

Basic client configuration example

import org.kie.server.api.marshalling.MarshallingFormat;
import org.kie.server.client.KieServicesClient;
import org.kie.server.client.KieServicesConfiguration;
import org.kie.server.client.KieServicesFactory;

public class MyConfigurationObject {

  private static final String URL = "http://localhost:8080/kie-server/services/rest/server";
  private static final String USER = "baAdmin";
  private static final String PASSWORD = "password@1";

  private static final MarshallingFormat FORMAT = MarshallingFormat.JSON;

  private static KieServicesConfiguration conf;
  private static KieServicesClient kieServicesClient;

  public static void initialize() {
    conf = KieServicesFactory.newRestConfiguration(URL, USER, PASSWORD);

    //If you use custom classes, such as Obj.class, add them to the configuration.
    Set<Class<?>> extraClassList = new HashSet<Class<?>>();
    extraClassList.add(Obj.class);
    conf.addExtraClasses(extraClassList);

    conf.setMarshallingFormat(FORMAT);
    kieServicesClient = KieServicesFactory.newKieServicesClient(conf);
  }
}

Advanced client configuration example with additional client services

import org.kie.server.api.marshalling.MarshallingFormat;
import org.kie.server.client.CaseServicesClient;
import org.kie.server.client.DMNServicesClient;
import org.kie.server.client.DocumentServicesClient;
import org.kie.server.client.JobServicesClient;
import org.kie.server.client.KieServicesClient;
import org.kie.server.client.KieServicesConfiguration;
import org.kie.server.client.KieServicesFactory;
import org.kie.server.client.ProcessServicesClient;
import org.kie.server.client.QueryServicesClient;
import org.kie.server.client.RuleServicesClient;
import org.kie.server.client.SolverServicesClient;
import org.kie.server.client.UIServicesClient;
import org.kie.server.client.UserTaskServicesClient;
import org.kie.server.api.model.instance.ProcessInstance;
import org.kie.server.api.model.KieContainerResource;
import org.kie.server.api.model.ReleaseId;

public class MyAdvancedConfigurationObject {

    // REST API base URL, credentials, and marshalling format
    private static final String URL = "http://localhost:8080/kie-server/services/rest/server";
    private static final String USER = "baAdmin";
    private static final String PASSWORD = "password@1";;

    private static final MarshallingFormat FORMAT = MarshallingFormat.JSON;

    private static KieServicesConfiguration conf;

    // KIE client for common operations
    private static KieServicesClient kieServicesClient;

    // Rules client
    private static RuleServicesClient ruleClient;

    // Process automation clients
    private static CaseServicesClient caseClient;
    private static DocumentServicesClient documentClient;
    private static JobServicesClient jobClient;
    private static ProcessServicesClient processClient;
    private static QueryServicesClient queryClient;
    private static UIServicesClient uiClient;
    private static UserTaskServicesClient userTaskClient;

    // DMN client
    private static DMNServicesClient dmnClient;

    // Planning client
    private static SolverServicesClient solverClient;

    public static void main(String[] args) {
        initializeKieServerClient();
        initializeDroolsServiceClients();
        initializeJbpmServiceClients();
        initializeSolverServiceClients();
    }

    public static void initializeKieServerClient() {
        conf = KieServicesFactory.newRestConfiguration(URL, USER, PASSWORD);
        conf.setMarshallingFormat(FORMAT);
        kieServicesClient = KieServicesFactory.newKieServicesClient(conf);
    }

    public static void initializeDroolsServiceClients() {
        ruleClient = kieServicesClient.getServicesClient(RuleServicesClient.class);
        dmnClient = kieServicesClient.getServicesClient(DMNServicesClient.class);
    }

    public static void initializeJbpmServiceClients() {
        caseClient = kieServicesClient.getServicesClient(CaseServicesClient.class);
        documentClient = kieServicesClient.getServicesClient(DocumentServicesClient.class);
        jobClient = kieServicesClient.getServicesClient(JobServicesClient.class);
        processClient = kieServicesClient.getServicesClient(ProcessServicesClient.class);
        queryClient = kieServicesClient.getServicesClient(QueryServicesClient.class);
        uiClient = kieServicesClient.getServicesClient(UIServicesClient.class);
        userTaskClient = kieServicesClient.getServicesClient(UserTaskServicesClient.class);
    }

    public static void initializeSolverServiceClients() {
        solverClient = kieServicesClient.getServicesClient(SolverServicesClient.class);
    }
}

2.1. Sending requests with the KIE Server Java client API

The KIE Server Java client API enables you to connect to KIE Server using REST protocol from your Java client application. You can use the KIE Server Java client API as an alternative to the KIE Server REST API to interact with your KIE containers and business assets (such as business rules, processes, and solvers) in Red Hat Process Automation Manager without using the Business Central user interface.

Prerequisites

  • KIE Server is installed and running.
  • You have kie-server user role access to KIE Server.
  • You have a Java project with Red Hat Process Automation Manager resources.

Procedure

  1. In your client application, ensure that the following dependencies have been added to the relevant classpath of your Java project:

    <!-- For remote execution on KIE Server -->
    <dependency>
      <groupId>org.kie.server</groupId>
      <artifactId>kie-server-client</artifactId>
      <version>${rhpam.version}</version>
    </dependency>
    
    <!-- For runtime commands -->
    <dependency>
      <groupId>org.drools</groupId>
      <artifactId>drools-compiler</artifactId>
      <scope>runtime</scope>
      <version>${rhpam.version}</version>
    </dependency>
    
    <!-- For debug logging (optional) -->
    <dependency>
      <groupId>ch.qos.logback</groupId>
      <artifactId>logback-classic</artifactId>
      <version>${logback.version}</version>
    </dependency>
  2. Download the Red Hat Process Automation Manager 7.8.0 Source Distribution from the Red Hat Customer Portal and navigate to ~/rhpam-7.8.0-sources/src/droolsjbpm-integration-$VERSION/kie-server-parent/kie-server-remote/kie-server-client/src/main/java/org/kie/server/client to access the KIE Server Java clients.
  3. In the ~/kie/server/client folder , identify the relevant Java client for the request you want to send, such as KieServicesClient to access client services for KIE containers and other assets in KIE Server.
  4. In your client application, create a .java class for the API request. The class must contain the necessary imports, KIE Server location and user credentials, a KieServicesClient object, and the client method to execute, such as createContainer and disposeContainer from the KieServicesClient client. Adjust any configuration details according to your use case.

    Creating and disposing a container

    import org.kie.server.api.marshalling.MarshallingFormat;
    import org.kie.server.client.KieServicesClient;
    import org.kie.server.client.KieServicesConfiguration;
    import org.kie.server.client.KieServicesFactory;
    import org.kie.server.api.model.KieContainerResource;
    import org.kie.server.api.model.ServiceResponse;
    
    public class MyConfigurationObject {
    
      private static final String URL = "http://localhost:8080/kie-server/services/rest/server";
      private static final String USER = "baAdmin";
      private static final String PASSWORD = "password@1";
    
      private static final MarshallingFormat FORMAT = MarshallingFormat.JSON;
    
      private static KieServicesConfiguration conf;
      private static KieServicesClient kieServicesClient;
    
      public static void initialize() {
        conf = KieServicesFactory.newRestConfiguration(URL, USER, PASSWORD);
    
      public void disposeAndCreateContainer() {
          System.out.println("== Disposing and creating containers ==");
    
          // Retrieve list of KIE containers
          List<KieContainerResource> kieContainers = kieServicesClient.listContainers().getResult().getContainers();
          if (kieContainers.size() == 0) {
              System.out.println("No containers available...");
              return;
          }
    
          // Dispose KIE container
          KieContainerResource container = kieContainers.get(0);
          String containerId = container.getContainerId();
          ServiceResponse<Void> responseDispose = kieServicesClient.disposeContainer(containerId);
          if (responseDispose.getType() == ResponseType.FAILURE) {
              System.out.println("Error disposing " + containerId + ". Message: ");
              System.out.println(responseDispose.getMsg());
              return;
          }
          System.out.println("Success Disposing container " + containerId);
          System.out.println("Trying to recreate the container...");
    
          // Re-create KIE container
          ServiceResponse<KieContainerResource> createResponse = kieServicesClient.createContainer(containerId, container);
          if(createResponse.getType() == ResponseType.FAILURE) {
              System.out.println("Error creating " + containerId + ". Message: ");
              System.out.println(responseDispose.getMsg());
              return;
          }
          System.out.println("Container recreated with success!");
          }
      }
    }

    You define service responses using the org.kie.server.api.model.ServiceResponse<T> object, where T represents the type of returned response. The ServiceResponse object has the following attributes:

    • String message: Returns the response message
    • ResponseType type: Returns either SUCCESS or FAILURE
    • T result: Returns the requested object

    In this example, when you dispose a container, the ServiceResponse returns a Void response. When you create a container, the ServiceResponse returns a KieContainerResource object.

    Note

    A conversation between a client and a specific KIE Server container in a clustered environment is secured by a unique conversationID. The conversationID is transferred using the X-KIE-ConversationId REST header. If you update the container, unset the previous conversationID. Use KieServiesClient.completeConversation() to unset the conversationID for Java API.

  5. Run the configured .java class from your project directory to execute the request, and review the KIE Server response.

    If you enabled debug logging, KIE Server responds with a detailed response according to your configured marshalling format, such as JSON.

    Example server response for a new KIE container (log):

    10:23:35.194 [main] INFO  o.k.s.a.m.MarshallerFactory - Marshaller extensions init
    10:23:35.396 [main] DEBUG o.k.s.client.balancer.LoadBalancer - Load balancer RoundRobinBalancerStrategy{availableEndpoints=[http://localhost:8080/kie-server/services/rest/server]} selected url 'http://localhost:8080/kie-server/services/rest/server'
    10:23:35.398 [main] DEBUG o.k.s.c.i.AbstractKieServicesClientImpl - About to send GET request to 'http://localhost:8080/kie-server/services/rest/server'
    10:23:35.440 [main] DEBUG o.k.s.c.i.AbstractKieServicesClientImpl - About to deserialize content:
     '{
      "type" : "SUCCESS",
      "msg" : "Kie Server info",
      "result" : {
        "kie-server-info" : {
          "id" : "default-kieserver",
          "version" : "7.11.0.Final-redhat-00003",
          "name" : "default-kieserver",
          "location" : "http://localhost:8080/kie-server/services/rest/server",
          "capabilities" : [ "KieServer", "BRM", "BPM", "CaseMgmt", "BPM-UI", "BRP", "DMN", "Swagger" ],
          "messages" : [ {
            "severity" : "INFO",
            "timestamp" : {
      "java.util.Date" : 1540814906533
    },
            "content" : [ "Server KieServerInfo{serverId='default-kieserver', version='7.11.0.Final-redhat-00003', name='default-kieserver', location='http://localhost:8080/kie-server/services/rest/server', capabilities=[KieServer, BRM, BPM, CaseMgmt, BPM-UI, BRP, DMN, Swagger], messages=null}started successfully at Mon Oct 29 08:08:26 EDT 2018" ]
          } ]
        }
      }
    }'
     into type: 'class org.kie.server.api.model.ServiceResponse'
    10:23:35.653 [main] DEBUG o.k.s.c.impl.KieServicesClientImpl - KieServicesClient connected to: default-kieserver version 7.11.0.Final-redhat-00003
    10:23:35.653 [main] DEBUG o.k.s.c.impl.KieServicesClientImpl - Supported capabilities by the server: [KieServer, BRM, BPM, CaseMgmt, BPM-UI, BRP, DMN, Swagger]
    10:23:35.653 [main] DEBUG o.k.s.c.impl.KieServicesClientImpl - Building services client for server capability KieServer
    10:23:35.653 [main] DEBUG o.k.s.c.impl.KieServicesClientImpl - No builder found for 'KieServer' capability
    10:23:35.654 [main] DEBUG o.k.s.c.impl.KieServicesClientImpl - Building services client for server capability BRM
    10:23:35.654 [main] DEBUG o.k.s.c.impl.KieServicesClientImpl - Builder 'org.kie.server.client.helper.DroolsServicesClientBuilder@6b927fb' for capability 'BRM'
    10:23:35.655 [main] DEBUG o.k.s.c.impl.KieServicesClientImpl - Capability implemented by {interface org.kie.server.client.RuleServicesClient=org.kie.server.client.impl.RuleServicesClientImpl@4a94ee4}
    10:23:35.655 [main] DEBUG o.k.s.c.impl.KieServicesClientImpl - Building services client for server capability BPM
    10:23:35.656 [main] DEBUG o.k.s.c.impl.KieServicesClientImpl - Builder 'org.kie.server.client.helper.JBPMServicesClientBuilder@4cc451f2' for capability 'BPM'
    10:23:35.672 [main] DEBUG o.k.s.c.impl.KieServicesClientImpl - Capability implemented by {interface org.kie.server.client.JobServicesClient=org.kie.server.client.impl.JobServicesClientImpl@1189dd52, interface org.kie.server.client.admin.ProcessAdminServicesClient=org.kie.server.client.admin.impl.ProcessAdminServicesClientImpl@36bc55de, interface org.kie.server.client.DocumentServicesClient=org.kie.server.client.impl.DocumentServicesClientImpl@564fabc8, interface org.kie.server.client.admin.UserTaskAdminServicesClient=org.kie.server.client.admin.impl.UserTaskAdminServicesClientImpl@16d04d3d, interface org.kie.server.client.QueryServicesClient=org.kie.server.client.impl.QueryServicesClientImpl@49ec71f8, interface org.kie.server.client.ProcessServicesClient=org.kie.server.client.impl.ProcessServicesClientImpl@1d2adfbe, interface org.kie.server.client.UserTaskServicesClient=org.kie.server.client.impl.UserTaskServicesClientImpl@36902638}
    10:23:35.672 [main] DEBUG o.k.s.c.impl.KieServicesClientImpl - Building services client for server capability CaseMgmt
    10:23:35.672 [main] DEBUG o.k.s.c.impl.KieServicesClientImpl - Builder 'org.kie.server.client.helper.CaseServicesClientBuilder@223d2c72' for capability 'CaseMgmt'
    10:23:35.676 [main] DEBUG o.k.s.c.impl.KieServicesClientImpl - Capability implemented by {interface org.kie.server.client.admin.CaseAdminServicesClient=org.kie.server.client.admin.impl.CaseAdminServicesClientImpl@2b662a77, interface org.kie.server.client.CaseServicesClient=org.kie.server.client.impl.CaseServicesClientImpl@7f0eb4b4}
    10:23:35.676 [main] DEBUG o.k.s.c.impl.KieServicesClientImpl - Building services client for server capability BPM-UI
    10:23:35.676 [main] DEBUG o.k.s.c.impl.KieServicesClientImpl - Builder 'org.kie.server.client.helper.JBPMUIServicesClientBuilder@5c33f1a9' for capability 'BPM-UI'
    10:23:35.677 [main] DEBUG o.k.s.c.impl.KieServicesClientImpl - Capability implemented by {interface org.kie.server.client.UIServicesClient=org.kie.server.client.impl.UIServicesClientImpl@223191a6}
    10:23:35.678 [main] DEBUG o.k.s.c.impl.KieServicesClientImpl - Building services client for server capability BRP
    10:23:35.678 [main] DEBUG o.k.s.c.impl.KieServicesClientImpl - Builder 'org.kie.server.client.helper.OptaplannerServicesClientBuilder@49139829' for capability 'BRP'
    10:23:35.679 [main] DEBUG o.k.s.c.impl.KieServicesClientImpl - Capability implemented by {interface org.kie.server.client.SolverServicesClient=org.kie.server.client.impl.SolverServicesClientImpl@77fbd92c}
    10:23:35.679 [main] DEBUG o.k.s.c.impl.KieServicesClientImpl - Building services client for server capability DMN
    10:23:35.679 [main] DEBUG o.k.s.c.impl.KieServicesClientImpl - Builder 'org.kie.server.client.helper.DMNServicesClientBuilder@67c27493' for capability 'DMN'
    10:23:35.680 [main] DEBUG o.k.s.c.impl.KieServicesClientImpl - Capability implemented by {interface org.kie.server.client.DMNServicesClient=org.kie.server.client.impl.DMNServicesClientImpl@35e2d654}
    10:23:35.680 [main] DEBUG o.k.s.c.impl.KieServicesClientImpl - Building services client for server capability Swagger
    10:23:35.680 [main] DEBUG o.k.s.c.impl.KieServicesClientImpl - No builder found for 'Swagger' capability
    10:23:35.681 [main] DEBUG o.k.s.client.balancer.LoadBalancer - Load balancer RoundRobinBalancerStrategy{availableEndpoints=[http://localhost:8080/kie-server/services/rest/server]} selected url 'http://localhost:8080/kie-server/services/rest/server'
    10:23:35.701 [main] DEBUG o.k.s.c.i.AbstractKieServicesClientImpl - About to send PUT request to 'http://localhost:8080/kie-server/services/rest/server/containers/employee-rostering3' with payload '{
      "container-id" : null,
      "release-id" : {
        "group-id" : "employeerostering",
        "artifact-id" : "employeerostering",
        "version" : "1.0.0-SNAPSHOT"
      },
      "resolved-release-id" : null,
      "status" : null,
      "scanner" : null,
      "config-items" : [ ],
      "messages" : [ ],
      "container-alias" : null
    }'
    10:23:38.071 [main] DEBUG o.k.s.c.i.AbstractKieServicesClientImpl - About to deserialize content:
     '{
      "type" : "SUCCESS",
      "msg" : "Container employee-rostering3 successfully deployed with module employeerostering:employeerostering:1.0.0-SNAPSHOT.",
      "result" : {
        "kie-container" : {
          "container-id" : "employee-rostering3",
          "release-id" : {
            "group-id" : "employeerostering",
            "artifact-id" : "employeerostering",
            "version" : "1.0.0-SNAPSHOT"
          },
          "resolved-release-id" : {
            "group-id" : "employeerostering",
            "artifact-id" : "employeerostering",
            "version" : "1.0.0-SNAPSHOT"
          },
          "status" : "STARTED",
          "scanner" : {
            "status" : "DISPOSED",
            "poll-interval" : null
          },
          "config-items" : [ ],
          "messages" : [ {
            "severity" : "INFO",
            "timestamp" : {
      "java.util.Date" : 1540909418069
    },
            "content" : [ "Container employee-rostering3 successfully created with module employeerostering:employeerostering:1.0.0-SNAPSHOT." ]
          } ],
          "container-alias" : null
        }
      }
    }'
     into type: 'class org.kie.server.api.model.ServiceResponse'

    If you encounter request errors, review the returned error code messages and adjust your Java configurations accordingly.

2.2. Supported KIE Server Java clients

The following are some of the Java client services available in the org.kie.server.client package of your Red Hat Process Automation Manager distribution. You can use these services to interact with related resources in KIE Server similarly to the KIE Server REST API.

  • KieServicesClient: Used as the entry point for other KIE Server Java clients, and used to interact with KIE containers
  • JobServicesClient: Used to schedule, cancel, re-queue, and get job requests
  • RuleServicesClient: Used to send commands to the server to perform rule-related operations, such as executing rules or inserting objects into the KIE session
  • SolverServicesClient: Used to perform all Red Hat Business Optimizer operations, such as getting the solver state and the best solution, or disposing a solver
  • ProcessServicesClient: Used to start, signal, and abort processes or work items
  • QueryServicesClient: Used to query processes, process nodes, and process variables
  • UserTaskServicesClient: Used to perform all user-task operations, such as starting, claiming, or canceling a task, and to query tasks by a specified field, such as by user or by process instances ID
  • UIServicesClient: Used to get String representation of forms (XML or JSON) and of a process image (SVG)
  • ProcessAdminServicesClient: Provides an interface for operations with process instances (found in ~/org/kie/server/client/admin)
  • UserTaskAdminServicesClient: Provides an interface for operations with user tasks (found in ~/org/kie/server/client/admin)

The getServicesClient method provides access to any of these clients:

RuleServicesClient rulesClient = kieServicesClient.getServicesClient(RuleServicesClient.class);

For the full list of available KIE Server Java clients, download the Red Hat Process Automation Manager 7.8.0 Source Distribution from the Red Hat Customer Portal and navigate to ~/rhpam-7.8.0-sources/src/droolsjbpm-integration-$VERSION/kie-server-parent/kie-server-remote/kie-server-client/src/main/java/org/kie/server/client.

2.3. Example requests with the KIE Server Java client API

The following are examples of KIE Server Java client API requests for basic interactions with KIE Server. For the full list of available KIE Server Java clients, download the Red Hat Process Automation Manager 7.8.0 Source Distribution from the Red Hat Customer Portal and navigate to ~/rhpam-7.8.0-sources/src/droolsjbpm-integration-$VERSION/kie-server-parent/kie-server-remote/kie-server-client/src/main/java/org/kie/server/client.

Listing KIE Server capabilities

You can use the org.kie.server.api.model.KieServerInfo object to identify server capabilities. The KieServicesClient client requires the server capability information to correctly produce service clients. You can specify the capabilities globally in KieServicesConfiguration; otherwise they are automatically retrieved from KIE Server.

Example request to return KIE Server capabilities

public void listCapabilities() {

  KieServerInfo serverInfo = kieServicesClient.getServerInfo().getResult();
  System.out.print("Server capabilities:");

  for (String capability : serverInfo.getCapabilities()) {
    System.out.print(" " + capability);
  }

  System.out.println();
}

Listing KIE containers in KIE Server

KIE containers are represented by the org.kie.server.api.model.KieContainerResource object. The list of resources is represented by the org.kie.server.api.model.KieContainerResourceList object.

Example request to return KIE containers from KIE Server

public void listContainers() {
    KieContainerResourceList containersList = kieServicesClient.listContainers().getResult();
    List<KieContainerResource> kieContainers = containersList.getContainers();
    System.out.println("Available containers: ");
    for (KieContainerResource container : kieContainers) {
        System.out.println("\t" + container.getContainerId() + " (" + container.getReleaseId() + ")");
    }
}

You can optionally filter the KIE container results using an instance of the org.kie.server.api.model.KieContainerResourceFilter class, which is passed to the org.kie.server.client.KieServicesClient.listContainers() method.

Example request to return KIE containers by release ID and status

public void listContainersWithFilter() {

    // Filter containers by releaseId "org.example:container:1.0.0.Final" and status FAILED
    KieContainerResourceFilter filter = new KieContainerResourceFilter.Builder()
            .releaseId("org.example", "container", "1.0.0.Final")
            .status(KieContainerStatus.FAILED)
            .build();

    // Using previously created KieServicesClient
    KieContainerResourceList containersList = kieServicesClient.listContainers(filter).getResult();
    List<KieContainerResource> kieContainers = containersList.getContainers();

    System.out.println("Available containers: ");

    for (KieContainerResource container : kieContainers) {
        System.out.println("\t" + container.getContainerId() + " (" + container.getReleaseId() + ")");
    }
}

Creating and disposing KIE containers in KIE Server

You can use the createContainer and disposeContainer methods in the KieServicesClient client to dispose and create KIE containers. In this example, when you dispose a container, the ServiceResponse returns a Void response. When you create a container, the ServiceResponse returns a KieContainerResource object.

Example request to dispose and re-create a KIE container

public void disposeAndCreateContainer() {
    System.out.println("== Disposing and creating containers ==");

    // Retrieve list of KIE containers
    List<KieContainerResource> kieContainers = kieServicesClient.listContainers().getResult().getContainers();
    if (kieContainers.size() == 0) {
        System.out.println("No containers available...");
        return;
    }

    // Dispose KIE container
    KieContainerResource container = kieContainers.get(0);
    String containerId = container.getContainerId();
    ServiceResponse<Void> responseDispose = kieServicesClient.disposeContainer(containerId);
    if (responseDispose.getType() == ResponseType.FAILURE) {
        System.out.println("Error disposing " + containerId + ". Message: ");
        System.out.println(responseDispose.getMsg());
        return;
    }
    System.out.println("Success Disposing container " + containerId);
    System.out.println("Trying to recreate the container...");

    // Re-create KIE container
    ServiceResponse<KieContainerResource> createResponse = kieServicesClient.createContainer(containerId, container);
    if(createResponse.getType() == ResponseType.FAILURE) {
        System.out.println("Error creating " + containerId + ". Message: ");
        System.out.println(responseDispose.getMsg());
        return;
    }
    System.out.println("Container recreated with success!");
}

Executing runtime commands in KIE Server

Red Hat Process Automation Manager supports runtime commands that you can send to KIE Server for asset-related operations, such as inserting or retracting objects in a KIE session or firing all rules. The full list of supported runtime commands is located in the org.drools.core.command.runtime package in your Red Hat Process Automation Manager instance.

You can use the org.kie.api.command.KieCommands class to insert commands, and use org.kie.api.KieServices.get().getCommands() to instantiate the KieCommands class. If you want to add multiple commands, use the BatchExecutionCommand wrapper.

Example request to insert an object and fire all rules

import org.kie.api.command.Command;
import org.kie.api.command.KieCommands;
import org.kie.server.api.model.ServiceResponse;
import org.kie.server.client.RuleServicesClient;
import org.kie.server.client.KieServicesClient;
import org.kie.api.KieServices;

import java.util.Arrays;

...

public void executeCommands() {

  String containerId = "hello";
  System.out.println("== Sending commands to the server ==");
  RuleServicesClient rulesClient = kieServicesClient.getServicesClient(RuleServicesClient.class);
  KieCommands commandsFactory = KieServices.Factory.get().getCommands();

  Command<?> insert = commandsFactory.newInsert("Some String OBJ");
  Command<?> fireAllRules = commandsFactory.newFireAllRules();
  Command<?> batchCommand = commandsFactory.newBatchExecution(Arrays.asList(insert, fireAllRules));

  ServiceResponse<String> executeResponse = rulesClient.executeCommands(containerId, batchCommand);

  if(executeResponse.getType() == ResponseType.SUCCESS) {
    System.out.println("Commands executed with success! Response: ");
    System.out.println(executeResponse.getResult());
  } else {
    System.out.println("Error executing rules. Message: ");
    System.out.println(executeResponse.getMsg());
  }
}

Note

A conversation between a client and a specific KIE Server container in a clustered environment is secured by a unique conversationID. The conversationID is transferred using the X-KIE-ConversationId REST header. If you update the container, unset the previous conversationID. Use KieServiesClient.completeConversation() to unset the conversationID for Java API.

Listing available business processes in a KIE container

You can use the QueryServicesClient client to list available process definitions. The QueryServicesClient methods use pagination, so in addition to the query you make, you must provide the current page and the number of results per page. In this example, the query starts on page 0 and lists the first 1000 results.

Example request to list business processes in KIE Server

public void listProcesses() {
    System.out.println("== Listing Business Processes ==");
    QueryServicesClient queryClient = kieServicesClient.getServicesClient(QueryServicesClient.class);
    List<ProcessDefinition> findProcessesByContainerId = queryClient.findProcessesByContainerId("rewards", 0, 1000);
    for (ProcessDefinition def : findProcessesByContainerId) {
        System.out.println(def.getName() + " - " + def.getId() + " v" + def.getVersion());
    }
}

Starting a business process in a KIE container

You can use the ProcessServicesClient client to start a business process. Ensure that any custom classes that you require for your process are added into the KieServicesConfiguration object, using the addExtraClasses() method.

Example request to start a business process

import java.util.HashMap;
import java.util.HashSet;
import java.util.Map;
import java.util.Set;

import javax.xml.bind.JAXBContext;
import javax.xml.bind.JAXBException;
import javax.xml.bind.Marshaller;

import org.kie.server.api.marshalling.MarshallingFormat;
import org.kie.server.client.KieServicesClient;
import org.kie.server.client.KieServicesConfiguration;
import org.kie.server.client.KieServicesFactory;
import org.kie.server.client.ProcessServicesClient;
...

public static void startProcess() {

  //Client configuration setup
  KieServicesConfiguration config = KieServicesFactory.newRestConfiguration(SERVER_URL, LOGIN, PASSWORD);

  //Add custom classes, such as Obj.class, to the configuration
  Set<Class<?>> extraClassList = new HashSet<Class<?>>();
  extraClassList.add(Obj.class);
  config.addExtraClasses(extraClassList);
  config.setMarshallingFormat(MarshallingFormat.JSON);

  // ProcessServicesClient setup
  KieServicesClient client = KieServicesFactory.newKieServicesClient(config);
  ProcessServicesClient processServicesClient = client.getServicesClient(ProcessServicesClient.class);

  // Create an instance of the custom class
  Obj obj = new Obj();
  obj.setOk("ok");

  Map<String, Object> variables = new HashMap<String, Object>();
  variables.put("test", obj);

  // Start the process with custom class
  processServicesClient.startProcess(CONTAINER, processId, variables);
}

Running a custom query

You can use the QueryDefinition object of the QueryServicesClient client to register and execute custom queries in KIE Server.

Example request to register and execute a custom query in KIE Server

// Client setup
KieServicesConfiguration conf = KieServicesFactory.newRestConfiguration(SERVER_URL, LOGIN, PASSWORD);
KieServicesClient client = KieServicesFactory.newKieServicesClient(conf);

// Get the QueryServicesClient
QueryServicesClient queryClient = client.getServicesClient(QueryServicesClient.class);

// Build the query
QueryDefinition queryDefinition = QueryDefinition.builder().name(QUERY_NAME)
        .expression("select * from Task t")
        .source("java:jboss/datasources/ExampleDS")
        .target("TASK").build();

// Specify that two queries cannot have the same name
queryClient.unregisterQuery(QUERY_NAME);

// Register the query
queryClient.registerQuery(queryDefinition);

// Execute the query with parameters: query name, mapping type (to map the fields to an object), page number, page size, and return type
List<TaskInstance> query = queryClient.query(QUERY_NAME, QueryServicesClient.QUERY_MAP_TASK, 0, 100, TaskInstance.class);

// Read the result
for (TaskInstance taskInstance : query) {
    System.out.println(taskInstance);
}

In this example, the target instructs the query service to apply default filters. Alternatively, you can set filter parameters manually. The Target class supports the following values:

public enum Target {
    PROCESS,
    TASK,
    BA_TASK,
    PO_TASK,
    JOBS,
    CUSTOM;
}