KR20210043865A - NGSI-LD API Wrapping Method - Google Patents

Abstract

Provided is an NGSI-LD API wrapping method. According to an embodiment of the present invention, the NGSI-LD API wrapping method comprises: creating an entity, property, and relationship of NGSI-LD as resources, individually; and generating an NGSI-LD resource that stores an entity ID and points to an entity resource indicating the entity. Accordingly, an NGSI-LD API is implemented on an oneM2M international standard platform so that data collected on the oneM2M platform can be utilized by external platforms and applications applying NGSI-LD.

Description

NGSI-LD API Wrapping Method {NGSI-LD API Wrapping Method}

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

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

In Figure 1, the information model of NGSI-LD is presented. The information model of NGSI-LD is composed of Entity, Property, and Relationship. Details on Entity, Property, and Relationship are shown in FIGS. 2, 3, and 4, respectively.

In the information model of NGSI-LD, Property and Relationship information for an entity is returned when an entity is searched. For example, as shown in FIG. 5, when a car, a police station, and a street light are configured as entities respectively, when an accident occurs in which a car hits a street light, as shown in FIG. 6, a car entity is searched and It returns property and relationship information for.

An object of the present invention is to provide an API Wrapping method for implementing NGSI-LD API in oneM2M platform as a method for enabling external platforms and applications to which NGSI-LD is applied to utilize data collected on oneM2M international standard platform. have.

According to an embodiment of the present invention for achieving the above object, a resource wrapping method includes the steps of generating entities, properties, and relationships of heterogeneous data as resources, respectively, according to standards of heterogeneous platforms; And storing an Entity ID of heterogeneous data and generating a first resource indicating an Entity resource indicating the entity.

The entity resource may have a property resource indicating a property and a relationship resource indicating a relationship as lower resources.

A resource wrapping method, characterized in that the resource indicating a property and relationship is a child resource and has a resource indicating another property and relationship.

The relationship resource may indicate a second resource having a different Entity ID from the first resource.

The first resource stores an Entity ID as an attribute, and the Entity, Property, and Relationship resources may store attribute values representing Entity, Property, and Relationship.

The resource wrapping method according to an embodiment of the present invention further includes the step of including and returning information of an Entity resource indicated by a first resource, a Property resource that the Entity resource has as a child resource, and a Relationship resource in a response upon inquiry request. can do.

The inquiry request is received by the virtual resource that processes the inquiry request, and a procedure to be performed with a postfix added to the ID of the virtual resource can be specified.

On the other hand, according to another embodiment of the present invention, the M2M platform, a communication unit for communicating with an external device; And a processor that generates an entity, a property, and a relationship of heterogeneous data according to the standards of heterogeneous platforms as resources, stores the Entity ID of the heterogeneous data, and generates a first resource indicating an Entity resource indicating the entity. .

As described above, according to the embodiments of the present invention, by implementing the NGSI-LD API on the oneM2M international standard platform, the data collected on the oneM2M platform can be utilized by external platforms and applications to which NGSI-LD is applied.

1 is an information model of NGSI-LD,
2 to 4 are diagrams showing details of Entity, Property, and Relationship of NGSI-LD,
5 and 6 are diagrams provided for explanation of information inquiry and return in NGSI-LD,
7 is a diagram provided to explain the concept of the NGSI-LD API;
8 and 9 are diagrams provided for explaining a method of mapping a oneM2M resource and an NGSI-LD Entity;
10 is a table showing an NGSI-LD to oneM2M resource path mapping scheme;
11 is a diagram illustrating NGSI-LD API Wrapping,
12 is a diagram showing a method of mapping NGSI-LD API to oneM2M standard;
13 is a diagram illustrating a response message returned when an NGSI-LD API is called;
14 is a diagram showing an IoT/M2M system to which the present invention is applicable, and,
15 is an internal block diagram of the electronic devices shown in FIG. 14.

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

oneM2M is an IoT middleware platform standard technology that is used to develop application services in various domains of IoT and smart city. The oneM2M standard, which aims for a RESTful architecture, defines a resource for storing data as Content Sharing Resource. 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 proposal is presented as a method for implementing the NGSI-LD API as an additional interface of the oneM2M platform. Through this, as shown in FIG. 7, the data collected on the oneM2M platform can be utilized by external platforms and applications to which NGSI-LD is applied.

8 is a diagram provided to explain a method of mapping a container/contentInstance resource among oneM2M resources and an NGSI-LD Entity.

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

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 (for example, resourceName), and points to a <container> resource (for example, entityResourceID) indicating the entity (refer to).

The <container> resource indicating Entity has a child <container> resource indicating Property and Relationship. And, <container> resources have attribute values (for example, label = ["NGSI-LD Property"]) to indicate Entity, Property, and Relationship.

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

Furthermore, in order to search NGSI-LD Entity, oneM2M defines a virtual resource for inquiry. In an embodiment of the present invention, the inquiry virtual resource is created as a child resource (entity in FIG. 8) of the <NGSI-LD> resource.

When a search request is made to the search virtual resource, the resource and sub-resource indicated by the <NGSI-LD> resource and Entity, Property, and Relationship information stored in the other resources indicated by these resources are configured as NGSI-LD Entity and returned.

That is, when calling the NGSI-LD API, the oneM2M platform converts the resources stored in the oneM2M resource tree format into an NGSI-LD entity and returns a response.

9 is a diagram provided for explaining a mapping method between a <flexContainer> resource among oneM2M resources and an NGSI-LD Entity.

In an embodiment of the present invention, the <NGSI-LD> resource is mapped to the <flexContainer> 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 (for example, resourceName), and points to a <flexContainer> resource (for example, entityResourceID) indicating the entity.

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

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

An API mapping method for supporting the NGSI-LD API through the above-described oneM2M resource mapping structure is presented in FIG. 10. 10 is a table showing an NGSI-LD to oneM2M resource path mapping scheme.

Here, for temporal and entities resources of NGSI-LD, the concept of oneM2M virtual resource that cannot be instantiated as a kind of API endpoint that provides specific functions is applied.

For example, when the oneM2M platform receives a request for /entities/{entityId} search API of NGSI-LD to search for a specific entity, as shown in FIG. In /{entityId}, identify the NGSI-LD resource corresponding to the entityId in the resource tree, merge the resources that store entity, property, and relationship information in the NGSI-LD resource to create and return the JSON-LD object of the NGSI-LD entity. do.

In addition, as shown in FIG. 12, a postfix is additionally defined to the virtual resource ID to map the NGSI-LD API call, and the NGSI-LD API may be called by targeting the temporal and entities virtual resources.

In this case, the procedure specified by postfix that comes after the virtual resource name is performed. In other words, different actions are performed for each mapped oneM2M resource (attribute modification, contentInstance is newly created, flexContainer is updated), and Query defined in NGSI-LD API is performed (e.g.: /entities/ with Query and only filtered entities are searched. ) Is possible.

Until now, as a method to enable external platforms and applications to which NGSI-LD is applied to utilize the data collected on the oneM2M international standard platform, a preferred embodiment of the API Wrapping method for implementing the NGSI-LD API on the oneM2M platform has been described. It has been described in detail.

On the other hand, when calling the NGSI-LD API (when transmitting a request message), a method for distinguishing between the existing oneM2M API and the NGSI-LD API is required. To this end, the resource path can be identified with a prefix for the NGSI-LD API (eg, ngsi-ld/entities/entity_001). In addition, it can be classified by a request message parameter (eg, NGSI-LD-Request: True). Also, the query of the NGSI-LD API can be used only when calling the NGSI-LD API, and can be mapped to the query string parameter of oneM2M.

In addition, when calling the NGSI-LD API, the response message reply is returned in the form of oneM2M existing response message, but as shown in FIG. 13, the Response Status Code response message parameter value is mapped and set with the processing result of NGSI-LD, The NGSI-LD response message can be included in the content response message parameter.

14 is a diagram showing an IoT/M2M system to which the present invention is applicable. The IoT/M2M system to which the present invention is applicable is, as shown in FIG. 14, a server 100-1, a gateway 100-21, 100-22, and a device 100-31, 100-32, 100-33. , 100-34), and various electronic devices are connected and constructed to enable communication with each other.

The number of electronic devices shown in FIG. 14, for example, a server 100-1, a gateway 100-21, 100-22, and a device 100-31, 100-32, 100- constituting an IoT/M2M system. 33, 100-34) is exemplary, and thus the technical idea of the present invention may be applied to a case of implementing differently from this.

Furthermore, it goes without saying that the connection structure of the electronic devices shown in FIG. 14 may also be replaced in other ways as necessary.

All electronic devices shown in FIG. 14 may function as the above-described oneM2M platform. That is, the server (100-1), the gateway (100-21, 100-22), the device (100-31, 100-32, 100-33, 100-34) all NGSI-LD API according to the embodiment of the present invention. Is able to support.

15 is an internal block diagram of the electronic devices shown in FIG. 14. The configurations necessary to implement the embodiment of the present invention are all of the server 100-1, the gateway 100-21, 100-22, and the devices 100-31, 100-32, 100-33, 100-34. Are common. Accordingly, in FIG. 15, these are collectively referred to as "100", and hereinafter, they are collectively referred to as electronic devices.

As shown in FIG. 15, electronic devices according to another embodiment of the present invention include a communication unit 110, a processor 120, a storage unit 130, and a function block 140.

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 electronic device, AE may not be included.

The processor 120 performs necessary procedures to support the NGSI-LD API presented above, and the storage unit 130 provides a storage space necessary for the processor 120 to provide a corresponding service.

The function block 140 performs the original function of the electronic device. For example, when the electronic device is the server 100-1, virtual machines providing user services correspond to the function block 140.

Meanwhile, 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 functions of the apparatus and method according to the present embodiment. Further, the technical idea according to various embodiments of the present invention may be implemented in the form of a computer-readable code recorded on a computer-readable recording medium. The computer-readable recording medium can be any data storage device that can be read by a computer and can store data. For example, a 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, a computer-readable code or program stored in a computer-readable recording medium may be transmitted through a network connected between computers.

In addition, although the 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 claimed in the claims. In addition, various modifications are possible by those of ordinary skill in the art, and these modifications should not be understood individually from the technical spirit or prospect of the present invention.

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

Claims (8)

Generating entities, properties, and relationships of heterogeneous data according to standards of heterogeneous platforms as resources, respectively; And
And generating a first resource indicating an Entity resource indicating an entity resource and storing an entity ID of heterogeneous data.
The method according to claim 1,
Entity resource,
Resource wrapping method, characterized in that it has a property resource indicating a property and a relationship resource indicating a relationship as lower resources.
The method according to claim 2,
Resources that indicate property and relationship are,
Resource wrapping method, characterized in that it has a resource indicating another property and relationship as a child resource.
The method of claim 3,
Relationship resource,
A resource wrapping method, characterized in that the first resource and the Entity ID indicate a second resource different from each other.
The method of claim 4,
The first resource is,
I am storing the Entity ID as an attribute,
Entity, Property, Relationship resources,
Resource wrapping method, characterized in that it stores attribute values representing entities, properties, and relationships.
The method of claim 4,
When the inquiry is requested, the step of returning information of an entity resource indicated by the first resource, a property resource that the entity resource has as a child resource, and a relationship resource in a response, and returning the information.
The method of claim 6,
Inquiry request,
A resource wrapping method, characterized in that a procedure to be performed with a postfix that is received by a virtual resource that processes an inquiry request and added to the ID of the virtual resource is specified.
A communication unit that communicates with an external device; And
Including; a processor that generates an entity, a property, and a relationship of heterogeneous data according to the standards of the heterogeneous platform as resources, stores the Entity ID of the heterogeneous data, and generates a first resource indicating an Entity resource indicating the entity; M2M platform characterized by.

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