Custom

A custom service task requires:

• A C# implementation of the IServiceTask interface
• A new step in the process
• Access control

C# implementation

using System.Threading.Tasks;
using Altinn.App.Core.Internal.Process.ProcessTasks.ServiceTasks;
using Altinn.App.Core.Models;
using Altinn.App.Models.model;
using Altinn.Platform.Storage.Interface.Models;

namespace Altinn.App.Code;

public class ExampleServiceTask : IServiceTask
{
    public string Type => "exampleServiceTask";

    public async Task<ServiceTaskResult> Execute(ServiceTaskContext context)
    {
        Instance instance = context.InstanceDataMutator.Instance;
        DataElement dataElement = instance.Data.Find(x => x.DataType == "model");

        var formData = (model)
            await context.InstanceDataMutator.GetFormData(new DataElementIdentifier(dataElement));

        if (formData.property1 != "true")
            return ServiceTaskResult.FailedAbortProcessNext();

        return ServiceTaskResult.Success();
    }
}

Add a serviceTask node in the BPMN process

The value in taskType must match the Type property in the C# implementation.

<bpmn:serviceTask id="ExampleServiceTask" name="Greeting">
    <bpmn:extensionElements>
        <altinn:taskExtension>
            <altinn:taskType>exampleServiceTask</altinn:taskType>
        </altinn:taskExtension>
    </bpmn:extensionElements>
    <bpmn:incoming>Flow_1yq6g64</bpmn:incoming>
    <bpmn:outgoing>Flow_1xowpt0</bpmn:outgoing>
</bpmn:serviceTask>

Access control

Service tasks run with the permissions of the user who advances the process (process next). Standard service tasks are authorized as write operations. For a user to have the rights to run a custom service task, the Type from the implementation must be added as an action in policy.xml.

Place it in the same location as other actions that the relevant user should have access to.

<xacml:AllOf>
    <xacml:Match MatchId="urn:oasis:names:tc:xacml:3.0:function:string-equal-ignore-case">
    <xacml:AttributeValue DataType="http://www.w3.org/2001/XMLSchema#string">exampleServiceTask</xacml:AttributeValue>
    <xacml:AttributeDesignator AttributeId="urn:oasis:names:tc:xacml:1.0:action:action-id" Category="urn:oasis:names:tc:xacml:3.0:attribute-category:action" DataType="http://www.w3.org/2001/XMLSchema#string" MustBePresent="false" />
    </xacml:Match>
</xacml:AllOf>