Application architecture Events component - Altinn Platform

The Events component is an a ASP.NET Core MVC Application exposing REST-API to Altinn Apps and other Altinn Platform components.

See event capabilities for functional description of the platforms event capabilities.

The solution is available at https://platform.altinn.cloud/events/api/v1.

API Structure

The API’s will be structured so the URLs are filtered queries into the events storage.

TODO: Verify proposed API structure

Instances events for Org

Endpoint
GET path: platform.altinn.no/events/api/v1/app/{org}/{appName}
Usage

This will be used by application owners to identify changes on instances for their applications.

Authorization

We will use scopes from Maskinporten to authorize access. In this way, it should also be possible for an org to delegate access to events for a given org/app.

The full detail for this API is described in this issue.

Request

The following url parameters and http headers have been defined. Person is given as a http header because of security.

Parameter Type Description
org string Required: the org owning the application
appName string Required: the application related to the event
after string Required**: the id of the last event processed by the client
from datetime Required**: The time (UTC) to search from
to datetime Optional: The time (UTC) to search up until
party string Optional: the partyId
type List<string> Optional: a list of event types
unit string Optional: the organisation number nine digits for reportee
person string (http header) Optional: the f or d number of the person
size int Optional: upper limit for number of returned events

* Needs to give one identifcator of the subject, unit,person or party parammeter.

** After or from is required

*** Source allows for escaping a single character _ or an undefined number of characters %

Response

Response includes a next header that can be used to get the events following the last event returned by the response. Query parameter after is inserted or replaced and holds the id of the last event returned in the reponse.

https://platform.tt02.altinn.no/events/api/v1/app/ttd/apps-test?after=5beae524-0b3d-4e3b-bf40-450575eaf5d6&from=2020-10-01 11:35:00

Response body includes a list of cloud events on the form

[
    {
        "id": "8c99c887-3861-4c2a-9ac9-178a20b1ee70",
        "source": "https://nav.apps.altinn.no/nav/app/instances/1234324/6fb3f738-6800-4f29-9f3e-1c66862656cd",
        "specversion": "1.x-wip",
        "type": "instance.created",
        "subject": "party/567890",
        "time": "2020-10-13T15:46:02.557971Z",
        "alternativesubject": "/person/01038712345",
        "data": "data field"
    },
    {
        "id": "5beae524-0b3d-4e3b-bf40-450575eaf5d6",
        "source": "https://nav.apps.altinn.no/nav/app/instances/1234324/6fb3f738-6800-4f29-9f3e-1c66862656cd",
        "specversion": "1.x-wip",
        "type": "instance.deleted",
        "subject": "party/567890",
        "time": "2020-10-14T10:33:33.022379Z",
        "alternativesubject": "/person/01038712345",
        "data": "data field"
    }
]

Events for a given party

A very common scenario is that a party needs to know about events for the party itself or other party that party has a relationship for (client, child unit++).

Endpoint
GET platform.altinn.no/events/api/v1/app/party
Usage

This is used by end users to see events for a given party. This will list all changes for a given party, identified with a partyId, person number or organisation number.

Authorization

Access to events needs to be authorized. To be able to read events, you need to have the read right for the given app for the given party.

The topic and subject would be used to identify the correct XACML-policy to use.

The operation would be read and the proccess task will be set to null. This way there would be no need to verify the current state of an instance.

The full detail for this API is described in this issue.

Request

The following url parameters and http headers has been defined. Person is given as a http header because of security.

Parameter Type Description
after string Required**: the id of the last event processed by the client
from datetime Required**: The time (UTC) to search from
to datetime Optional: The time (UTC) to search up until
party string Required* the partyId
type List<string> Optional: a list of event types
source List<string> (regex allowed)*** Optional: a list of strings to match the event source
unit string Required* the organisation number nine digits
person string (http header) Required* the f or d number of the person
size int Optional: upper limit for number of returned events
* Needs to give one identifcator of the subject, unit,person or party parammeter.

** After or from is required

*** Source allows for escaping a single character _ or an undefined number of characters %

Response

Response includes a next header that can be used to get the events following the last event returned by the response. Query parameter after is inserted or replaced and holds the id of the last event returned in the reponse.

https://platform.tt02.altinn.no/events/api/v1/app/party?after=5beae524-0b3d-4e3b-bf40-450575eaf5d6&from=2020-10-01 11:35:00

We have this example

[{
  "source":  "https://skd.apps.altinn.no/skd/skattemelding/234234422/2acb1253-07b3-4463-9ff5-60dc82fd59f8",
  "subject": "party/234234422",
  "type": "instance.process.completed",
  "time":  "2020-02-20T09:06:50.3736712Z",
  "id": "91f2388f-bd8c-4647-8684-fd9f68af5b14",
  "ssid":"orgno:974760673"
}]

To be able to read this event, the authenticated party is required to have the rights for SKD/Skattmelding for the party 234234422. This is something it gets throug roles for that specific application.

Adding events

Endpoint
POST {platformurl}/events/api/v1/app

This returns the created ID for the event.

Usage

This is used by the application to publish app events. Events are submitted as CloudEvents.

A CloudEvent consists of a number of attributes, such as the ID of the event and the type of the event.
The following attributes is used by the Events component.

Attribute Name Type Note
id String Optional. The ID of the event. A CloudEvent is uniquely identified with its source and id. The Events component will assign the id of the event.
source String (URI-reference) Required. The source of the event.
specversion String Required. The version of CloudEvents Specification the Cloud Event uses.
type String Required. The type of the event.
subject String Required. The subject of the event.
time String (Timestamp) Optional. The timestamp when the event happens. The Events component will set this.
alternativesubject String Optional. The alternative subject of the event.

We have this example

[{
    "specversion": "1.0", 
    "type": "instance.created",
    "source":  "skd/skattemelding/234234422/2acb1253-07b3-4463-9ff5-60dc82fd59f8",
    "id": "91f2388f-bd8c-4647-8684-fd9f68af5b14",
    "time": "2020-02-20T08:00:06.4014168Z",
    "subject": "party/234234422",
    "alternativesubject": "party/131555662"
}]

The full detail for this API is described in this issue.