DICOM PS3.18 2019d - Web Services

11 Worklist Service and Resources

11.1 Overview

The Worklist Service, also known as UPS-RS, defines a RESTful interface to the Unified Procedure Step Service SOP Classes defined in Section B.26 “Unified Procedure Step Information Object Definition” in PS3.3 and Section CC “Unified Procedure Step Service and SOP Classes (Normative)” in PS3.4, in which UPS behavior is specified.

The Worklist Service manages a single Worklist containing one or more Workitems. Each Workitem represents a procedure step. User agents and origin servers can create, retrieve, update, search for, and change the state of Workitems. See Section GGG “Unified Worklist and Procedure Step - UPS (Informative)” in PS3.17 for an overview of Worklists and Workitems (UPS Instances).

11.1.1 Resource Description

There are three resources defined by this service:

worklist

A collection of Workitems managed by the origin server.

workitem

A dataset containing the Attributes specified in Section CC.2.5.1.3 “UPS Attribute Service Requirements” in PS3.4.

subscription

A resource that specifies a Subscriber, to whom notifications about changes in the resource's state should be sent.

In the Worklist Service, the Workitem is identified by a Workitem UID, which corresponds to the Affected SOP Instance UID and Requested SOP Instance UID used in the PS3.4 UPS Service.

The following URI Template variables are used in the definitions of the resources throughout Chapter 11.

{workitem}

the Workitem UID.

{aetitle}

The Application Entity Title of a Subscriber.

The Worklist Service manages a UPS Worklist and its Workitems. The URI Templates defined by this service are specified in Table 11.1.1-1.

Table 11.1.1-1. Resources, URI Templates and Descriptions

Resource

URI Template

Description

Worklist

/

The Base URI of the Worklist Service. A Worklist contains and manages a collection of Workitems. There is only one Worklist per service.

All Workitems

/workitems

The Workitems resource contains the entire collection of workitems in the Worklist.

Workitem

/workitems/{workitem}

The Workitem resource contains a single Workitem.

Workitem State

/workitems/{workitem}/state

The Workitem State resource is used to change the state of a Workitem.

Workitem Request Cancellation

/workitems/{workitem}/cancelrequest

The Workitem Cancel resource is used to request the cancellation of a Workitem.

Workitem Subscription

/workitems/{workitem}/subscribers/{aetitle}

The Subscription to a Workitem.

Worklist Subscription

/workitems/1.2.840.10008.5.1.4.34.5/subscribers/{aetitle}

The Workitem Subscription resource contains a Subscription to the Worklist

Filtered Worklist Subscription

/workitems/1.2.840.10008.5.1.4.34.5.1/subscribers/{aetitle}

The Workitem Subscribers resource contains a single Worklist Subscriber.


11.1.1.1 Workitems

A Workitem is what is referred to in Annex CC “Unified Procedure Step Service and SOP Classes (Normative)” in PS3.4 as a procedure step.

Workitems represent a variety of steps such as: Image Processing, Quality Control, Computer Aided Detection, Interpretation, Transcription, Report Verification, or Printing. The steps may or may not be formally scheduled.

11.1.1.2 Web Services and DIMSE Terminology

Table 11.1.1-2. Correspondence between RESTful and DIMSE Terminology

RESTful Term

DIMSE Term

Worklist

Worklist

Workitem

UPS Instance

Deletion Lock

Deletion Lock

Filter

Matching Keys

Matching Key

Matching Key

Subscribe

Subscribe

Unsubscribe

Unsubscribe

Subscription

Subscription

Subscription Generator

Worklist Subscription

Filtered Worklist Subscription

Subscriber

Subscriber

Suspend Subscription

Suspend Worklist Subscription

Notification Connection

Association

Transaction

N-GET, N-SET, N-ACTION

Notification

N-EVENT-REPORT


11.1.2 Common Query Parameters

The origin server shall support Query Parameters as required in Table 11.1.2-1.

The user agent shall supply in the request Query Parameters as required in Table 11.1.2-1.

Table 11.1.2-1. Common Query Parameters

Name

Value

Usage

Section

User Agent

Origin Server

Accept

media-type

M

M

Section 8.3.3.1

Accept-Charset

charset

O

M

Section 8.3.3.2


See also Section 8.4.

11.1.3 Common Media Types

The origin server shall support the media types listed as Default or Required in Table 11.1.3-1.

Table 11.1.3-1. Default, Required, and Optional Media Types

Media Type

Usage

Section

application/dicom+json

Default

Section 8.7.3.2

multipart/related; type="application/dicom+xml"

Required

Section 8.7.3.2


multipart/related; type="application/dicom+xml"; boundary={boundary}

Specifies that the payload is a multipart message body where each part is a PS3.19 Native DICOM Model XML Infoset containing the appropriate Workitem Attributes. See Section A.1 in PS3.19 .

application/dicom+json

Specifies that the payload is a JSON array containing Workitems, and each Workitem contains the appropriate Attributes. SeeSection F.2.

The transactions shall not support Metadata or Bulkdata objects.

DICOM PS3.18 2019d - Web Services