@dih-fbn/ngsi-ld

A lightweight TypeScript client designed to interact with NGSI-LD context brokers.

[!WARNING] This package is currently under development for our organization's specific needs. It is not intended for production use yet and APIs may change.

Installation

npm i @dih-fbn/ngsi-ld

Usage

Import the library

import { ContextBroker, Entity } from "@dih-fbn/ngsi-ld";

Create a context broker instance

const contexBrokerUrl = "https://context-broker.example.com";
const contextUrl = "https://example.com/context.jsonld";
const contextBroker = new ContextBroker(contexBrokerUrl, contextUrl);

Get multiple entities

const cities = await contextBroker.findEntities({ type: "City" });

Get an entity

const paris = await contextBroker.findEntity("urn:ngsi-ld:City:paris");

Create an entity

const london = new Entity();
london.setId("urn:ngsi-ld:City:london");
london.setType("City");
london.setProperty("name", "London");
london.setGeoProperty("location", "Point", [-0.127758, 51.507351]);
london.setRelationship("hasCountry", "urn:ngsi-ld:Country:uk");
await contextBroker.insertEntity(london);

Update an entity

thermostat.setProperty("targetTemperature", 19, new Date().toISOString());
await contextBroker.updateEntity(london);

Update an entity attribute

sensor.setProperty("status", "ready", new Date().toISOString());
await contextBroker.updateEntityAttribute(sensor, "status");

Get subscriptions

const subscriptions = await contextBroker.findSubscriptions();

Get a subscription

const subscription = await contextBroker.findSubscription("urn:ngsi-ld:Subscription:00000000-0000-0000-0000-000000000000");

Create a subscription

const subscription = new Subscription(...);
await contextBroker.insertSubscription(subscription);

Delete a subscription

await contextBroker.deleteSubscription(subscription.getId());

API specification

ContextBroker

| Method | Parameters | Return value | | --------------------- | ------------------------------------------------------------------ | ----------------------- | | constructor | url: string, contextUrl?: string | ContextBroker | | findEntities | { type?: string, query?: string, limit?: number, offset?: number } | Promise<Entity[]> | | findEntity | id: string | Promise | | insertEntity | entity: Entity | Promise | | updateEntity | entity: Entity | Promise | | updateEntityAttribute | entity: Entity, name: string | Promise | | findSubscriptions | { limit?: number, offset?: number } | Promise<Subscription[]> | | findSubscription | id: string | Promise | | insertSubscription | subscription: Subscription | Promise | | deleteSubscription | subscriptionId: string | Promise |

Entity

| Method name | Parameters | Return value | | --------------- | ----------------------------------------------------------------- | ------------------------------------------ | | constructor | data?: any | Entity | | getId | — | string | | getType | — | string | | setId | id: string | void | | setType | type: string | void | | isAttribute | name: string | boolean | | isProperty | name: string | boolean | | isRelationship | name: string | boolean | | isGeoProperty | name: string | boolean | | getProperty | name: string | any | null | | getRelationship | name: string | string | string[] | null | | getGeoProperty | name: string | { type: string, coordinates: any } | null | | setProperty | name: string, value: any, observedAt?: string | void | | setRelationship | name: string, object: string | string[], observedAt?: string | void | | setGeoProperty | name: string, type: string, coordinates: any, observedAt?: string | void | | toObject | — | any |