Add end-point for extracting buses from a network

pom.xml

@@ -39,6 +39,21 @@
             <artifactId>ktor-server-netty-jvm</artifactId>
             <version>${ktor.version}</version>
         </dependency>
+        <dependency>
+            <groupId>io.ktor</groupId>
+            <artifactId>ktor-serialization-kotlinx-json-jvm</artifactId>
+            <version>${ktor.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>io.ktor</groupId>
+            <artifactId>ktor-server-test-host-jvm</artifactId>
+            <version>${ktor.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>io.ktor</groupId>
+            <artifactId>ktor-server-content-negotiation-jvm</artifactId>
+            <version>${ktor.version}</version>
+        </dependency>
         <dependency>
             <groupId>org.jetbrains.kotlin</groupId>
             <artifactId>kotlin-test-junit5</artifactId>
@@ -56,6 +71,18 @@
                 <version>${kotlin.version}</version>
 
                 <extensions>true</extensions>
+                <configuration>
+                    <compilerPlugins>
+                        <plugin>kotlinx-serialization</plugin>
+                    </compilerPlugins>
+                </configuration>
+                <dependencies>
+                    <dependency>
+                        <groupId>org.jetbrains.kotlin</groupId>
+                        <artifactId>kotlin-maven-serialization</artifactId>
+                        <version>${kotlin.version}</version>
+                    </dependency>
+                </dependencies>
             </plugin>
             <plugin>
                 <groupId>org.apache.maven.plugins</groupId>

src/main/ApiDataModels.kt

@@ -1,11 +1,13 @@
 package com.github.statnett.loadflowservice
 
 import com.powsybl.iidm.network.Network
+import kotlinx.serialization.Serializable
 
 /**
  * Class for holding properties from the PowsbyBl bus class that are
  * returned via the Rest API
  */
+@Serializable
 data class BusProperties(
     val id: String,
     val voltage: Double,
@@ -14,13 +16,16 @@ data class BusProperties(
     val reactivePower: Double,
 )
 
-fun busPropertiesFromNetwork(network: Network) =
-    network.getBusView().getBusStream().map {
-        BusProperties(
-            id = it.getId(),
-            voltage = it.getV(),
-            angle = it.getAngle(),
-            activePower = it.getP(),
-            reactivePower = it.getQ(),
-        )
-    }
+fun busPropertiesFromNetwork(network: Network): List<BusProperties> {
+    return network.busView.buses
+        .map { bus ->
+            BusProperties(
+                id = bus.id,
+                voltage = bus.v,
+                angle = bus.angle,
+                activePower = bus.p,
+                reactivePower = bus.q,
+            )
+        }
+        .toList()
+}

src/main/ApiUtil.kt

@@ -0,0 +1,11 @@
+package com.github.statnett.loadflowservice
+
+import java.io.ByteArrayInputStream
+
+fun busesFromRequest(
+    type: String,
+    body: ByteArray,
+): List<BusProperties> {
+    val network = networkFromStream(type, ByteArrayInputStream(body))
+    return busPropertiesFromNetwork(network)
+}

src/main/Application.kt

@@ -0,0 +1,52 @@
+package com.github.statnett.loadflowservice
+
+import io.ktor.http.HttpStatusCode
+import io.ktor.http.content.PartData
+import io.ktor.http.content.forEachPart
+import io.ktor.http.content.streamProvider
+import io.ktor.serialization.kotlinx.json.*
+import io.ktor.server.application.*
+import io.ktor.server.plugins.contentnegotiation.*
+import io.ktor.server.request.*
+import io.ktor.server.response.*
+import io.ktor.server.routing.*
+
+fun main(args: Array<String>): Unit = io.ktor.server.netty.EngineMain.main(args)
+
+fun Application.module() {
+    install(ContentNegotiation) {
+        json()
+    }
+
+    routing {
+        get("/") {
+            call.respondText("Hello, world!")
+        }
+
+        post("/get-buses") {
+            var fileName = ""
+            var fileBytes = byteArrayOf()
+
+            val multiPartData = call.receiveMultipart()
+
+            multiPartData.forEachPart { part ->
+                when (part) {
+                    is PartData.FileItem -> {
+                        fileName = part.originalFileName as String
+                        fileBytes = part.streamProvider().readBytes()
+                    }
+
+                    else -> {}
+                }
+                part.dispose()
+            }
+
+            if (fileName == "") {
+                call.response.status(HttpStatusCode.UnprocessableEntity)
+            } else {
+                val busProps = busesFromRequest(fileName, fileBytes)
+                call.respond(busProps)
+            }
+        }
+    }
+}

src/main/resources/application.conf

@@ -0,0 +1,9 @@
+ktor {
+    deployment {
+        port = 8080
+        port = ${?PORT}
+    }
+    application {
+        modules = [ com.github.statnett.loadflowservice.ApplicationKt.module ]
+    }
+}

src/test/ApiDataModelsTest.kt

@@ -1,14 +1,13 @@
+import com.github.statnett.loadflowservice.busPropertiesFromNetwork
+import com.powsybl.ieeecdf.converter.IeeeCdfNetworkFactory
 import kotlin.test.Test
 import kotlin.test.assertEquals
-import com.powsybl.ieeecdf.converter.IeeeCdfNetworkFactory
-import com.github.statnett.loadflowservice.busPropertiesFromNetwork
 
 class ApiDataModelTest {
-
     @Test
     fun `Should be 14 buses in test network`() {
         val network = IeeeCdfNetworkFactory.create14()
         val buses = busPropertiesFromNetwork(network)
         assertEquals(buses.count(), 14)
     }
-}
+}

src/test/ApplicationTest.kt

@@ -0,0 +1,75 @@
+import com.powsybl.ieeecdf.converter.IeeeCdfNetworkFactory
+import io.ktor.client.request.*
+import io.ktor.client.request.forms.formData
+import io.ktor.client.request.forms.submitFormWithBinaryData
+import io.ktor.client.statement.*
+import io.ktor.http.Headers
+import io.ktor.http.HttpHeaders
+import io.ktor.http.HttpStatusCode
+import io.ktor.server.testing.testApplication
+import java.io.File
+import java.nio.file.Paths
+import java.util.Properties
+import kotlin.test.Test
+import kotlin.test.assertContains
+import kotlin.test.assertEquals
+import kotlin.test.assertTrue
+
+class ApplicationTest {
+    @Test
+    fun testRoot() =
+        testApplication {
+            val response = client.get("/")
+            assertEquals(HttpStatusCode.OK, response.status)
+            assertEquals("Hello, world!", response.bodyAsText())
+        }
+
+    @Test
+    fun `test get buses returns 422 on missing file content`() =
+        testApplication {
+            val response =
+                client.submitFormWithBinaryData(
+                    url = "/get-buses",
+                    formData =
+                        formData {
+                            append("network", "not file content")
+                        },
+                )
+            assertEquals(HttpStatusCode.UnprocessableEntity, response.status)
+        }
+
+    @Test
+    fun `test receive 14 buses for 14 bus network`() =
+        testApplication {
+            // Initialize temporary file
+            val file = File.createTempFile("network", ".xiidm")
+            file.deleteOnExit()
+
+            IeeeCdfNetworkFactory.create14().write("XIIDM", Properties(), Paths.get(file.path))
+
+            val response =
+                client.submitFormWithBinaryData(
+                    url = "/get-buses",
+                    formData =
+                        formData {
+                            append(
+                                "network",
+                                file.readBytes(),
+                                Headers.build {
+                                    append(HttpHeaders.ContentDisposition, "filename=${file.name}")
+                                },
+                            )
+                        },
+                )
+            assertEquals(HttpStatusCode.OK, response.status)
+            assertEquals(response.headers["Content-Type"], "application/json; charset=UTF-8")
+            val body: String = response.bodyAsText()
+
+            // Roughly validate contant
+            assertTrue(body.startsWith("[{"))
+            assertTrue(body.endsWith("}]"))
+
+            val busString = "{\"id\":\"VL1_0\",\"voltage\":143.1,\"angle\":0.0,\"activePower\":0.0,\"reactivePower\":0.0}"
+            assertContains(body, busString)
+        }
+}