Support NGSI-LD QueryEntities endpoint for lazy attributes

Author: jason-fox

lib/services/northBound/contextServer-NGSI-LD.js

@@ -506,6 +506,9 @@ function handleMergePatchNgsiLD(req, res, next) {
  * @param {Object} res              Response that will be sent.
  */
 function handleQueryNgsiLD(req, res, next) {
+    const returnAsArray = req.query.id;
+    req.params.entity = req.params.entity || req.query.id || '';
+
     function getName(element) {
         return element.name;
     }
@@ -641,7 +644,7 @@ function handleQueryNgsiLD(req, res, next) {
             next(error);
         } else {
             logger.debug(context, 'Query from [%s] handled successfully.', req.get('host'));
-            res.status(200).json(result);
+            res.status(200).json(returnAsArray ? [result] : result);
         }
     }
 
@@ -793,7 +796,6 @@ function loadUnsupportedEndpointsNGSILD(router) {
     const unsupportedEndpoint = function (req, res) {
         return res.status(501).send(new errors.MethodNotSupported(req.method, req.path));
     };
-    router.get('/ngsi-ld/v1/entities', unsupportedEndpoint);
     router.post('/ngsi-ld/v1/entities', unsupportedEndpoint);
     router.delete('/ngsi-ld/v1/entities/:entity', unsupportedEndpoint);
     router.delete('/ngsi-ld/v1/entities/:entity/attrs/:attr', unsupportedEndpoint);
@@ -846,6 +848,7 @@ function loadContextRoutesNGSILD(router) {
     for (i = 0; i < queryPaths.length; i++) {
         router.get(queryPaths[i], [handleQueryNgsiLD, ErrorHandlingNgsiLD('Query')]);
     }
+    router.get('/ngsi-ld/v1/entities', [handleQueryNgsiLD, ErrorHandlingNgsiLD('Query')]);
     router.post('/notify', [
         middlewares.ensureType,
         middlewares.validateJson(notificationTemplateNgsiLD),

test/unit/ngsi-ld/lazyAndCommands/lazy-devices-test.js

@@ -226,7 +226,7 @@ describe('NGSI-LD - IoT Agent Lazy Devices', function () {
         it('should call the device handler for each of the contexts');
     });
 
-    describe('When a context query arrives to the IoT Agent', function () {
+    describe('When a context query arrives to the IoT Agent using retrieveEntity', function () {
         const options = {
             url:
                 'http://localhost:' +
@@ -294,6 +294,76 @@ describe('NGSI-LD - IoT Agent Lazy Devices', function () {
         });
     });
 
+    describe('When a context query arrives to the IoT Agent using queryEntities', function () {
+        const options = {
+            url:
+                'http://localhost:' +
+                iotAgentConfig.server.port +
+                '/ngsi-ld/v1/entities/?id=urn:ngsi-ld:Light:light1&attrs=dimming',
+            method: 'GET',
+            headers: {
+                'fiware-service': 'smartgondor',
+                'fiware-servicepath': 'gardens'
+            }
+        };
+        const sensorData = [
+            {
+                id: 'Light:light1',
+                type: 'Light',
+                dimming: {
+                    type: 'Percentage',
+                    value: 19
+                }
+            }
+        ];
+
+        beforeEach(function (done) {
+            nock.cleanAll();
+
+            contextBrokerMock = nock('http://192.168.1.1:1026')
+                .matchHeader('fiware-service', 'smartgondor')
+                .post(
+                    '/ngsi-ld/v1/csourceRegistrations/',
+                    utils.readExampleFile(
+                        './test/unit/ngsi-ld/examples/contextAvailabilityRequests/registerIoTAgent1.json'
+                    )
+                )
+                .reply(201, null, { Location: '/ngsi-ld/v1/csourceRegistrations/6319a7f5254b05844116584d' });
+
+            contextBrokerMock
+                .matchHeader('fiware-service', 'smartgondor')
+                .post('/ngsi-ld/v1/entityOperations/upsert/')
+                .reply(204);
+
+            async.series([apply(iotAgentLib.activate, iotAgentConfig), apply(iotAgentLib.register, device1)], done);
+        });
+
+        it('should return the information querying the underlying devices', function (done) {
+            const expectedResponse = [
+                utils.readExampleFile(
+                    './test/unit/ngsi-ld/examples/contextProviderResponses/queryInformationResponse.json'
+                )
+            ];
+
+            iotAgentLib.setDataUpdateHandler(function (id, type, service, subservice, attributes, callback) {
+                callback(null);
+            });
+
+            iotAgentLib.setDataQueryHandler(function (id, type, service, subservice, attributes, callback) {
+                id.should.equal('urn:ngsi-ld:' + device1.type + ':' + device1.id);
+                type.should.equal(device1.type);
+                attributes[0].should.equal('dimming');
+                callback(null, sensorData[0]);
+            });
+
+            request(options, function (error, response, body) {
+                should.not.exist(error);
+                body.should.eql(expectedResponse);
+                done();
+            });
+        });
+    });
+
     describe('When a context query arrives to the IoT Agent and no handler is set', function () {
         const options = {
             url:

test/unit/ngsi-ld/ngsiService/unsupported-endpoints-test.js

@@ -108,16 +108,6 @@ describe('NGSI-LD - Unsupported Endpoints', function () {
     });
 
     describe('When accessing an Unsupported Endpoint', function () {
-        it('GET /entities should return a valid NSGI-LD error message', function (done) {
-            const options = {
-                url: 'http://localhost:' + iotAgentConfig.server.port + '/ngsi-ld/v1/entities',
-                method: 'GET'
-            };
-            request(options, function (error, response, body) {
-                response.statusCode.should.equal(501);
-                done();
-            });
-        });
         it('POST /entities should return a valid NSGI-LD error message', function (done) {
             const options = {
                 url: 'http://localhost:' + iotAgentConfig.server.port + '/ngsi-ld/v1/entities',