Technical - how to include a ReadMessage task in the app process

Description

As part of #1330 we have defined that we need to support messages as part of an instance

The UX has not been finalized, but there are some technical issues that need to be resolved even if not all details are in place.

This analysis needs to identify those and suggest a solution

Considerations

What are the scenarios supported?

A instance is created with a message w/wo binary attachments
A instance is created with a message w/wo binary attachments and user can choose to respond with a form
A instance is created with a message w/wo attachment and a pre instantiated form

Type of BPMN Task

The type of BPMN task needed to be supported is suggested to be called "message"

<bpmn2:definitions id="Altinn_Data_Confirmation_Process_Definition"
  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  xmlns:bpmn2="http://www.omg.org/spec/BPMN/20100524/MODEL"
  xmlns:bpmndi="http://www.omg.org/spec/BPMN/20100524/DI"
  xmlns:dc="http://www.omg.org/spec/DD/20100524/DC"
  xmlns:di="http://www.omg.org/spec/DD/20100524/DI"
  xmlns:altinn="http://altinn.no"
  xsi:schemaLocation="http://www.omg.org/spec/BPMN/20100524/MODEL BPMN20.xsd"
  targetNamespace="http://bpmn.io/schema/bpmn" >
  <bpmn2:process id="Altinn_Data_Confirmation_Process" isExecutable="false">
    <bpmn2:startEvent id="StartEvent_1">
      <bpmn2:outgoing>SequenceFlow_1</bpmn2:outgoing>
    </bpmn2:startEvent>
 <bpmn2:task id="Task_1" name="Les melding" altinn:tasktype="data">
      <bpmn2:incoming>SequenceFlow_1</bpmn2:incoming>
      <bpmn2:outgoing>SequenceFlow_2</bpmn2:outgoing>
    </bpmn2:task>
    <bpmn2:task id="Task_2" name="Fyll ut skjema" altinn:tasktype="data">
      <bpmn2:incoming>SequenceFlow_2</bpmn2:incoming>
      <bpmn2:outgoing>SequenceFlow_3</bpmn2:outgoing>
    </bpmn2:task>
    <bpmn2:task id="Task_3" name="Bekreft skjemadata" altinn:tasktype="confirmation">
      <bpmn2:incoming>SequenceFlow_3</bpmn2:incoming>
      <bpmn2:outgoing>SequenceFlow_4</bpmn2:outgoing>
    </bpmn2:task>
    <bpmn2:endEvent id="EndEvent_1">
      <bpmn2:incoming>SequenceFlow_4</bpmn2:incoming>
    </bpmn2:endEvent>
    <bpmn2:sequenceFlow id="SequenceFlow_1" sourceRef="StartEvent_1" targetRef="Task_1" />
    <bpmn2:sequenceFlow id="SequenceFlow_2" sourceRef="Task_1" targetRef="Task_2" />
    <bpmn2:sequenceFlow id="SequenceFlow_3" sourceRef="Task_2" targetRef="Task_3" />
    <bpmn2:sequenceFlow id="SequenceFlow_4" sourceRef="Task_3" targetRef="EndEvent_1" />
  </bpmn2:process>
</bpmn2:definitions>

This task would require Read right to read the message.

We need to decide what is the right needed to move forward in that process.

How to define the message datatype

In the below Applicationmetadata.json there is defined a datalement with type altinnmessage.


{
  "id": "ttd/apps-test",
  "org": "ttd",
  "title": {
    "nb": "test app (simple)"
  },
  "dataTypes": [
    {
      "id": "default",
      "allowedContentTypes": [
        "application/xml"
      ],
      "appLogic": {
        "autoCreate": true,
        "classRef": "Altinn.App.Models.Skjema"
      },
      "taskId": "Task_1",
      "maxCount": 1,
      "minCount": 1
    },
    {
      "id": "altinnmessage",
      "allowedContentTypes": [
        "application/json"
      ],
      "maxCount": 0,
      "minCount": 0
    },
    {
      "id": "d84913c1-2b32-4ab0-a605-409be875bae6",
      "taskId": "Task_1",
      "maxSize": 1,
      "maxCount": 3,
      "minCount": 1
    }
  ],
  "partyTypesAllowed": {
    "bankruptcyEstate": false,
    "organisation": false,
    "person": false,
    "subUnit": false
  },
  "created": "2020-01-14T11:44:56.6415699Z",
  "createdBy": "jeeva",
  "lastChanged": "2020-01-14T11:44:56.6415721Z",
  "lastChangedBy": "jeeva"
}

a) What would be the max and minimum values. (Assumption 0 so it is controlled by the org) b) How can we differentiate between different messages in the same instance.

How to instantiate an instance with a message

We would use the Post Method on instance controller to instansiate it.

This method parses the multirequest including all attachments in the [ExtractrInstanceTemplateMetod]https://github.com/Altinn/altinn-studio/blob/master/src/Altinn.Apps/AppTemplates/AspNet/Altinn.App.Api/Controllers/InstancesController.cs#L575)

a) How is Process moved to first task? (Is this already handled?) b) What about data. Can we instantiate without any data? We probably need to update.

How to present message view

App frontend would need to be updated to support presenting the correct view when instance is in message task.

a) Instance is instantiated with a message and task status is the message

How to instantiate a form as a response to a message

How can we let the user instantiate a form from the message and move to the data task in the BPMN Process

How to go to a form that is already instantiated.

How can a user be redirected from the message task to a data task with a given dataid.

How to update read status on a correspondence message?

Do we need read status?

How can we present a message from the archive?

For regular receipt we show receipt application with pdf. Should we do the same with message

How to support multiple messages.

There will be instances with multiple messages. Do we need to mark them in specific way. To we need to be attached to a specific task?

How to support attachments

It should be possible to add links to other data elements so they can be shown as attachments

How to prevent overwrite of message

We need to clarify what is the standard behavior when it comes to deleting and overwriting of the message and attachments related to that message. Should it be allowed?

The assumption is that it would not be allowed. The delete method should check if the data element is a message and if so not allow the deletion of it.

How to prevent message attachment deletion

In the same way on deletion of dataelement we should check if it is referenced in a message.

How to prevent deletion of a message

We need to define if it is possible to delete a message from org.

Could we add a flag to datalement to as readonly

How to support senders information on a message

We need to define how the sender of a message can be sent. In Altinn 2 this is disconnected from the org.

How to support archiving of instance when submitting form is an option

If this is required we would need a way to

Deletion of messages Multiple messages?

Tasks

[ ] Define what is the type of BPMN task that supports message
[ ] Define how to instantiate an instance with a message
[ ] Define how to instantiate an instance with a message and a form dataelement

Development task

[ ] Define new BPMN Task Type "message"
[ ] Update instansiation API so an app with first task message can be instansiated without any message / Instansiated with message as body
[ ] Implement message view to be shown in message task
[ ] Implement message view to be shown when opened from another task. (reuse?)
[ ] Update App frontend navigation to show message view when the dataId is a message
[ ] Update Receipt page to view show message
[ ] Update medataapi to return information that a given dataid is a message
[ ] Update receipt component to support presentation of message in instance.
[ ] Update dataAPi so it is not possible to overwrite message (confirm need)

Altinn / altinn-studio