KR20220078994A - NGSI-LD API Subscription Wrapping Method - Google Patents

Abstract

A method for wrapping NGSI-LD API subscriptions is provided. In the NGSI-LD subscription wrapping method according to an embodiment of the present invention, a first resource indicating NGSI-LD information is generated using an NGSI-LD standard, which is a standard of a heterogeneous platform, and a second resource indicating an entity of NGSI-LD information. Creates a first subscription resource indicating a subscription to the entity under the first resource, and creates a second subscription resource for subscribing to a second resource under the second resource. Accordingly, the oneM2M platform can provide the Subscription/Notification function of the NGSI-LD interface.

Description

NGSI-LD API Subscription Wrapping Method

The present invention relates to API Wrapping technology, and more particularly, to a method for implementing NGSI-LD API Subscription Wrapping in an international standard platform such as oneM2M.

NGSI-LD (Next Generation Service Interface - Linked Data) is a standard interface of ETSI that adds the information model concept to support Linked Data to the NGSI-9/10 API of the conventional OMA. It can express relationships between data in various domains. .

The information model of NGSI-LD is presented in FIG. 1 . The information model of NGSI-LD consists of Entity, Property, and Relationship. Details of Entity, Property, and Relationship are shown in FIGS. 2, 3 and 4, respectively.

In order to expand the base of information utilization, a plan is needed to link the information model of NGSI-LD with the oneM2M platform. In particular, there is a need for a method to provide the subscription/notification function of the NGSI-LD interface in the oneM2M platform.

The present invention has been devised to solve the above problems, and an object of the present invention is to provide a subscription/notification function of an NGSI-LD interface in oneM2M platform, and to provide an NGSI-LD API Subscription Wrapping method. is in providing.

According to an embodiment of the present invention for achieving the above object, an NGSI-LD subscription wrapping method includes: a first generating step of generating a first resource indicating NGSI-LD information using an NGSI-LD standard that is a standard of a heterogeneous platform; a second generation step of generating a second resource indicating an entity of NGSI-LD information; A third generation step of creating a first subscription resource indicating a subscription to the entity under the first resource; and a fourth generation step of creating a second subscription resource for subscribing to a second resource under the second resource.

The NGSI-LD subscription wrapping method according to an embodiment of the present invention may further include, when the first subscription resource is modified, modifying the second subscription resource according to the modified content.

The third generation step generates a first subscription resource indicating a subscription for a plurality of entities, and the fourth generation step generates second subscription resources under a plurality of second resources for a plurality of entities, respectively, The third generation step may record the ID list of the second subscription resources in the first subscription resource.

In the fourth generation step, when the entity type value is included as an attribute in the first subscription resource, second subscription resources may be created below the second resources having the entity type value.

In the fourth generation step, if watchedAttributes is set in the first subscription resource, subscription resources are created under the resources representing watchedAttributes among the sub-resources of the second resource, and if watchedAttributes is not set in the first subscription resource, the Subscription resources are created below all sub-resources of the 2 resources, and a second resource indicating the property of NGSI-LD information and a third resource indicating a relationship of NGSI-LD information may be included.

The second subscription resource may include an indicator for transmission in the NGSI-LD notification message format, and may include the ID of the first subscription resource for policy confirmation for notification message transmission.

The second subscription resource may include a notificationURI including an endpoint that the platform converts the notification message of the second subscription resource into an NGSI-LD notification message and transmits.

On the other hand, according to another embodiment of the present invention, in a computer-readable recording medium, the NGSI-LD standard, which is a standard of a heterogeneous platform, a first generating step of generating a first resource indicating NGSI-LD information; a second generation step of generating a second resource indicating an entity of NGSI-LD information; a third generation step of creating a first subscription resource representing a subscription to an Entity under the first resource; A program capable of performing the NGSI-LD subscription wrapping method, comprising: a fourth generating step of generating a second subscription resource under the second resource of the NGSI-LD information is recorded.

As described above, according to embodiments of the present invention, the oneM2M platform can provide the Subscription/Notification function of the NGSI-LD interface through NGSI-LD API Subscription Wrapping.

1 is an information model of NGSI-LD;
2 to 4 are diagrams showing details of Entity, Property, and Relationship of NGSI-LD;
5 is a mapping table between Entity/Subscription of NGSI-LD standard and resource/Subscription of oneM2M standard;
6 is a diagram provided for explanation of a mapping method between an Entity of the NGSI-LD standard and a <container> resource of oneM2M;
7 is a diagram provided for explanation of a mapping method between an Entity of the NGSI-LD standard and a <flexcontainer> resource of oneM2M;
8 is a diagram provided for explaining a mapping method between a subscription of the NGSI-LD standard and a <subscription> resource of oneM2M;
9 is a diagram provided for description of subscription-related attributes of the NGSI-LD API;
10 is a block diagram illustrating a hardware configuration of the oneM2M platform according to another embodiment of the present invention.

Hereinafter, the present invention will be described in more detail with reference to the drawings.

The oneM2M standard that aims for a RESTful architecture defines a resource for storing data as a Content Sharing Resource, and by using resource types such as container, contentInstance, and flexContainer, data that can be shared between applications can be stored on the platform and management functions can be utilized. .

In an embodiment of the present invention, an API Wrapping design plan for NGSI-LD API as an additional interface of the oneM2M platform is presented so that data collected on the oneM2M platform can be utilized by external platforms and applications to which NGSI-LD is applied.

Furthermore, we present the NGSI-LD API Subscription Wrapping design so that the oneM2M platform can provide the Subscription/Notification function of the NGSI-LD interface.

5 is a path mapping table between Entity/Subscription of NGSI-LD standard and resource/Subscription of oneM2M standard. A mapping method using the illustrated table will be described in detail below.

6 is a diagram provided to explain a mapping method between an entity of the NGSI-LD standard and a <container> resource of oneM2M.

To express NGSI-LD information in oneM2M, a <NGSI-LD> resource is defined as a new resource type, and Entity, Property, and Relationship of NGSI-LD information are created as resources, respectively.

In an embodiment of the present invention, the <NGSI-LD> resource is mapped to a container/contentInstance resource among Data Sharing Resources defined by oneM2M.

This <NGSI-LD> resource has the Entity ID defined in the NGSI-LD API as an attribute (eg, resourceName), and points to (refer to) a <container> resource (eg, entityResourceID) indicating the Entity.

A <container> resource indicating an entity has a lower <container> resource indicating a Property and a Relationship. And, <container> resources have attribute values (eg, label = ["NGSI-LD Property"]) for indicating Entity, Property, and Relationship.

The oneM2M platform stores the attribute values of Entity, Property, and Relationship defined in the NGSI-LD API as a <contentInstance> resource as a child of the corresponding <container> resource.

A <container> resource indicating a property or relationship can have a <container> resource indicating another property or relationship as a child. In addition, the <container> resource indicating the relationship may point to another <NGSI-LD> resource.

7 is a diagram provided to explain a mapping method between an entity of the NGSI-LD standard and a <flexcontainer> resource of oneM2M.

In an embodiment of the present invention, the <NGSI-LD> resource is mapped to a <flexContainer> resource among Data Sharing Resources defined in oneM2M.

This <NGSI-LD> resource has the Entity ID defined in the NGSI-LD API as an attribute (eg, resourceName), and points to a <flexContainer> resource (eg, entityResourceID) indicating the Entity.

The <flexContainer> resource indicating the Entity has a lower <flexContainer> resource indicating the Property and Relationship. And, <flexContainer> resources have property values (eg, label = ["NGSI-LD Property"]) for indicating Entity, Property, and Relationship.

The oneM2M platform stores the property values of Entity, Property, and Relationship defined in the NGSI-LD API as a <flexContainer> resource as a child of the <flexContainer> resource.

A <flexContainer> resource indicating a property or relationship can have a <flexContainer> resource indicating another property or relationship as a child. In addition, the <flexContainer> resource indicating the relationship may point to another <NGSI-LD> resource.

8 is a diagram provided to explain a mapping method between a subscription of the NGSI-LD standard and a <subscription> resource of oneM2M.

When a <NGSI-LD-subscription> resource creation request is made from the NGSI-LD interface by the subscription request, the CSE (Common Service Entity) of the oneM2M platform creates a oneM2M subscription for the NGSI-LD Entity (entities attribute) that is the target of the subscription. do.

Specifically, a <NGSI-LD-subscription> resource indicating a subscription to an NGSI-LD Entity is created under the <NGSI-LD> resource, and a <container> resource is created under the <container> resource indicating the NGSI-LD Entity. Create a <subscription> resource for resource subscription.

If the <NGSI-LD-subscription> resource is modified, the <subscription> resource created under the <container> resource indicating the NGSI-LD Entity according to the modification must also be modified.

When the <NGSI-LD-subscription> resource sets a subscription to two or more NGSI-LD entities, create <subscription> resources in the <container> resources indicating the NGSI-LD entities that have been subscribed, respectively, and Record the ID list of <subscription> resources in the <NGSI-LD-subscription> resource as the subscriptionIDs attribute.

The <NGSI-LD-subscription> resource may include the entities attribute. If the entities attribute is included in <NGSI-LD-subscription> and only the entity type value is set in the corresponding attribute, <container> under <container> resources indicating NGSI-LD entities having the set entity type value. Create <subscription> resources for subscribing to resources, respectively.

On the other hand, if watchedAttributes is set in the <NGSI-LD-subscription> resource, <subscription> resources for resource subscription are created under the resources that show watchedAttributes among the sub-resources of the <container> resource indicating the NGSI-LD Entity. do.

The sub-resources of the <container> resource indicating the NGSI-LD Entity refer to the <container> resource indicating the NGSI-LD Property, the <container> resource indicating the NGSI-LD Relationship, and their sub <container> resources. .

If watchedAttributes is not set in the <NGSI-LD-subscription> resource, <subscription> resources for resource subscription are created under all sub-resources of the <container> resource pointing to the NGSI-LD Entity. 8 shows a result of generating <subscription> resources in all sub-resources of the <container> resource indicating the NGSI-LD Entity.

When the resource indicating the NGSI-LD Entity is configured as a <container> resource as shown in FIG. 8, when the <subscription> resource is created, the notificationEventType property of the <subscription> resource is set as a sub-resource creation event.

Meanwhile, the resource indicating the NGSI-LD Entity may be configured as a <flexContainer> resource as shown in FIG. 7 . In this case, the notificationEventType property of the <subscription> resource is set as a subscription target resource modification event.

The <subscription> resource may include an indicator for transmission in the NGSI-LD notification message format. Also, a <NGSI-LD-subscription> resource ID may be included in the <subscription> resource, and this ID may be used to confirm a policy (eg, throttling) for sending a notification message.

As an alternative to the method of transmitting the NGSI-LD notification message, when the <subscription> resource is created, notificationURI may be set as an endpoint through which the oneM2M platform can convert the oneM2M notification message into an NGSI-LD notification message and transmit it.

When creating an NGSI-LD Subscription, the NGSI-LD Subscription setting must be converted for the oneM2M Subscription setting, which is as follows. Attributes for configuring NGSI-LD Subscription are shown in FIG. 9 .

To this end, a <subscription> resource is created only when the isActive attribute of the <NGSI-LD-subscription> resource is set to true. Thereafter, when the isActive attribute of the <NGSI-LD-subscription> resource is changed to false, the <subscription> resource is deleted.

If the isActive attribute of the <NGSI-LD-subscription> resource is set to false, the <subscription> resource is not created. Thereafter, when the isActive attribute of the <NGSI-LD-subscription> resource is changed to true, the <subscription> resource is created.

When the expires attribute is set in the <NGSI-LD-subscription> resource, the expirationTime attribute value is set in the <NGSI-LD-subscription> resource and the <subscription> resources created thereby.

In addition, when the throttling attribute is set in the <NGSI-LD-subscription> resource, the <subscription> resources created by this are converted to the rateLimit attribute and set.

And, when the q or temporalQ attribute is set in the <NGSI-LD-subscription> resource, it is converted into an eventNotificationCriteria (event notification policy) attribute in the <subscription> resources generated thereby and is set.

So far, as a method for providing the subscription/notification function of the NGSI-LD interface in the oneM2M platform, a preferred embodiment of the NGSI-LD API Subscription Wrapping method has been described in detail.

A hardware configuration of the oneM2M platform capable of implementing the CSE presented in the above embodiment will be described below with reference to FIG. 10 . 10 is a block diagram of the oneM2M platform according to an embodiment of the present invention.

As shown in FIG. 10 , the oneM2M platform according to an embodiment of the present invention can be constructed as a server system or a computing system including a communication unit 110 , a processor 120 , and a storage unit 130 .

The communication unit 110 is a communication interface means for communicating with an external device and accessing an external network.

The processor 120 includes at least one Application Entity (AE) and a Common Service Entity (CSE). Depending on the type and function of the M2M platform, AE may not be included.

The processor 120 performs procedures necessary for NGSI-LD API Entiti/Resource Wrapping and NGSI-LD API Subscription Wrapping presented above, and the storage unit 130 performs the procedures necessary for the processor 120 for Wrapping. It provides the necessary storage space.

On the other hand, it goes without saying that the technical idea of the present invention can be applied to a computer-readable recording medium containing a computer program for performing the functions of the apparatus and method according to the present embodiment. In addition, the technical ideas according to various embodiments of the present invention may be implemented in the form of computer-readable codes recorded on a computer-readable recording medium. The computer-readable recording medium may be any data storage device readable by the computer and capable of storing data. For example, the computer-readable recording medium may be a ROM, RAM, CD-ROM, magnetic tape, floppy disk, optical disk, hard disk drive, or the like. In addition, the computer-readable code or program stored in the computer-readable recording medium may be transmitted through a network connected between computers.

In addition, although preferred embodiments of the present invention have been illustrated and described above, the present invention is not limited to the specific embodiments described above, and the technical field to which the present invention belongs without departing from the gist of the present invention as claimed in the claims In addition, various modifications are possible by those of ordinary skill in the art, and these modifications should not be individually understood from the technical spirit or perspective of the present invention.

NGSI-LD : Next Generation Service Interface - Linked Data
Entity: entity
Property : Property
Relationship: relationship
container, contentInstance, flexContainer : oneM2M resource
subscription : subscription

Claims (8)

a first generating step of generating a first resource representing NGSI-LD information using an NGSI-LD standard, which is a standard of a heterogeneous platform;
a second generation step of generating a second resource indicating an entity of NGSI-LD information;
a third generation step of creating a first subscription resource representing a subscription to an Entity under the first resource;
NGSI-LD subscription wrapping method comprising a; a fourth generating step of generating a second subscription resource for subscribing to a second resource under the second resource.
The method according to claim 1,
When the first subscription resource is modified, modifying the second subscription resource according to the modification; NGSI-LD subscription wrapping method further comprising a.
The method according to claim 1,
The third generation step is
Create a first subscription resource representing a subscription to a plurality of entities,
The fourth generation step is
Creates second subscription resources under a plurality of second resources for a plurality of entities, respectively,
The third generation step is
NGSI-LD subscription wrapping method, characterized in that the ID list of the second subscription resources is recorded in the first subscription resource.
The method according to claim 1,
The fourth generation step is
NGSI-LD subscription wrapping method, characterized in that when the entity type value is included in the first subscription resource as an attribute, second subscription resources are created below the second resources having the entity type value.
The method according to claim 1,
The fourth generation step is
If watchedAttributes is set in the first subscription resource, subscription resources are created under the resources representing watchedAttributes among the sub-resources of the second resource,
If watchedAttributes is not set on the first subscription resource, subscription resources are created under all sub-resources of the second resource,
An NGSI-LD subscription wrapping method comprising: a second resource indicating a property of NGSI-LD information; and a third resource indicating a relationship between NGSI-LD information.
The method according to claim 1,
The second subscription resource,
Including an indicator for transmission in the NGSI-LD notification message format,
NGSI-LD subscription wrapping method, characterized in that it contains the ID of the first subscription resource for policy confirmation for notification message transmission.
The method according to claim 1,
The second subscription resource,
An NGSI-LD subscription wrapping method, characterized in that the platform includes a notificationURI in which an endpoint that converts the notification message of the second subscription resource into an NGSI-LD notification message and transmits is recorded.
a first generating step of generating a first resource representing NGSI-LD information using an NGSI-LD standard, which is a standard of a heterogeneous platform;
a second generation step of generating a second resource indicating an entity of NGSI-LD information;
a third generation step of creating a first subscription resource representing a subscription to an Entity under the first resource;
A computer-readable program capable of performing the NGSI-LD subscription wrapping method comprising; a fourth generation step of generating a second subscription resource under the second resource of the NGSI-LD information; recording medium.

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