feature/get temporal data for an entity id (#30)

.gitignore

@@ -5,3 +5,10 @@
 build
 out
 
+### IntelliJ IDEA ###
+.idea
+*.iws
+*.iml
+*.ipr
+out/
+

kngsild/src/main/kotlin/io/egm/kngsild/api/TemporalService.kt

@@ -6,6 +6,7 @@ import arrow.core.left
 import arrow.core.right
 import io.egm.kngsild.model.ApplicationError
 import io.egm.kngsild.model.ContextBrokerError
+import io.egm.kngsild.model.ResourceNotFound
 import io.egm.kngsild.utils.*
 import io.egm.kngsild.utils.JsonUtils.serializeObject
 import org.slf4j.LoggerFactory
@@ -56,4 +57,42 @@ class TemporalService(
             }
         }
     }
+
+    fun retrieve(
+        entityId: URI,
+        queryParams: Map<String, String>,
+        contextUrl: String
+    ): Either<ApplicationError, NgsildEntity> {
+        val params: String = HttpUtils.paramsUrlBuilder(queryParams)
+        return authUtils.getToken().flatMap {
+            val request = HttpRequest
+                .newBuilder()
+                .uri(
+                    URI.create("$contextBrokerUrl$temporalApiRootPath/$entityId$params")
+                )
+                .setHeader("Accept", HttpUtils.APPLICATION_JSONLD)
+                .setHeader("Link", HttpUtils.httpLinkHeaderBuilder(contextUrl))
+                .setHeader("Authorization", "Bearer $it")
+                .GET().build()
+
+            try {
+                logger.debug("Issuing retrieve: /ngsi-ld/v1/temporal/entities/$entityId$params")
+                val httpResponse = HttpUtils.httpClient.send(request, HttpResponse.BodyHandlers.ofString())
+                logger.debug("Http response status code: ${httpResponse.statusCode()}")
+                logger.debug("Http response body: ${httpResponse.body()}")
+
+                if (httpResponse.statusCode() == HttpURLConnection.HTTP_OK)
+                    JsonUtils.deserializeObject(httpResponse.body()).right()
+                else if (httpResponse.statusCode() == HttpURLConnection.HTTP_NOT_FOUND)
+                    ResourceNotFound("Entity not found").left()
+                else ContextBrokerError(
+                    "Failed to retrieve entity, " +
+                            "received ${httpResponse.statusCode()} (${httpResponse.body()}) from context broker"
+                ).left()
+            } catch (e: IOException) {
+                val errorMessage = e.message ?: "Error encountered while processing GET request"
+                ContextBrokerError(errorMessage).left()
+            }
+        }
+    }
 }

kngsild/src/test/kotlin/io/egm/kngsild/api/TemporalServiceTest.kt

@@ -4,13 +4,11 @@ import arrow.core.right
 import com.github.tomakehurst.wiremock.WireMockServer
 import com.github.tomakehurst.wiremock.client.WireMock
 import com.github.tomakehurst.wiremock.core.WireMockConfiguration
-import io.egm.kngsild.utils.AuthUtils
-import io.egm.kngsild.utils.NgsiLdAttributeNG
-import io.egm.kngsild.utils.NgsiLdUtils
+import io.egm.kngsild.utils.*
 import io.egm.kngsild.utils.UriUtils.toUri
-import io.egm.kngsild.utils.groupByProperty
 import org.junit.jupiter.api.*
 import org.mockito.Mockito
+import java.net.URI
 
 @TestInstance(TestInstance.Lifecycle.PER_CLASS)
 class TemporalServiceTest {
@@ -96,4 +94,33 @@ class TemporalServiceTest {
                 )
         )
     }
+
+    @Test
+    fun `it should retrieve temporal data of an entityId`() {
+        val entityId = gimmeNgsildEntity("urn:ngsi-ld:Sensor:01".toUri()!!, emptyMap())
+        WireMock.stubFor(
+            WireMock.get(WireMock.urlMatching("/ngsi-ld/v1/temporal/entities/urn:ngsi-ld:Sensor:01"))
+                .willReturn(WireMock.ok().withBody(JsonUtils.serializeObject(entityId)))
+        )
+
+        val mockedAuthUtils = Mockito.mock(AuthUtils::class.java)
+        Mockito.`when`(
+            mockedAuthUtils.getToken()
+        ).thenReturn("token".right())
+        val temporalService = TemporalService("http://localhost:8089", mockedAuthUtils)
+
+        val response = temporalService.retrieve(
+            "urn:ngsi-ld:Sensor:01".toUri()!!,
+            emptyMap(),
+            NgsiLdUtils.coreContext
+        )
+
+        Assertions.assertTrue(response.isRight())
+        Assertions.assertTrue(response.exists { it["id"] == "urn:ngsi-ld:Sensor:01" })
+    }
+
+    private fun gimmeNgsildEntity(id: URI, attributes: Map<String, Any>): NgsildEntity =
+        mapOf(
+            "id" to id
+        ).plus(attributes)
 }