Add a first test

latte/build.gradle.kts

@@ -26,6 +26,11 @@ dependencies {
     implementation("org.jetbrains:annotations:24.1.0")
     compileOnly("org.apache.logging.log4j:log4j-api:2.22.0")
 
+    // JUnit testing framework
+    val junitVersion = "5.10.1"
+    testImplementation("org.junit.jupiter:junit-jupiter-api:$junitVersion")
+    testRuntimeOnly("org.junit.jupiter:junit-jupiter-engine:$junitVersion")
+
 }
 
 repositories {
@@ -36,4 +41,8 @@ kotlin {
     jvmToolchain(17)
 }
 
+tasks.test {
+    useJUnitPlatform()
+}
+
 defaultTasks("build")

latte/src/main/java/gg/beemo/latte/broker/BrokerSubclients.kt

@@ -3,6 +3,7 @@ package gg.beemo.latte.broker
 import com.squareup.moshi.JsonAdapter
 import com.squareup.moshi.Moshi
 import gg.beemo.latte.util.MoshiInstantAdapter
+import gg.beemo.latte.util.MoshiUnitAdapter
 import gg.beemo.latte.util.SuspendingCountDownLatch
 import kotlinx.coroutines.CoroutineScope
 import kotlinx.coroutines.coroutineScope
@@ -30,6 +31,7 @@ sealed class BaseSubclient(
         //  https://github.com/square/moshi#custom-type-adapters
         @JvmStatic
         protected val moshi: Moshi = Moshi.Builder()
+            .add(MoshiUnitAdapter())
             .add(MoshiInstantAdapter())
             .build()
     }

latte/src/main/java/gg/beemo/latte/util/MoshiAdapters.kt

@@ -1,18 +1,37 @@
 package gg.beemo.latte.util
 
+import com.squareup.moshi.FromJson
 import com.squareup.moshi.JsonAdapter
 import com.squareup.moshi.JsonReader
 import com.squareup.moshi.JsonWriter
+import com.squareup.moshi.ToJson
 import java.time.Instant
 
 class MoshiInstantAdapter : JsonAdapter<Instant>() {
 
+    @FromJson
     override fun fromJson(reader: JsonReader): Instant? {
         return Instant.ofEpochMilli(reader.nextLong())
     }
 
+    @ToJson
     override fun toJson(writer: JsonWriter, value: Instant?) {
         writer.value(value?.toEpochMilli())
     }
 
 }
+
+class MoshiUnitAdapter : JsonAdapter<Unit>() {
+
+    @FromJson
+    override fun fromJson(reader: JsonReader): Unit? {
+        reader.skipValue()
+        return Unit
+    }
+
+    @ToJson
+    override fun toJson(writer: JsonWriter, value: Unit?) {
+        writer.nullValue()
+    }
+
+}

latte/src/test/kotlin/gg/beemo/latte/broker/BrokerClientTest.kt

@@ -0,0 +1,28 @@
+package gg.beemo.latte.broker
+
+import kotlinx.coroutines.runBlocking
+import org.junit.jupiter.api.Assertions
+import org.junit.jupiter.api.Test
+
+class BrokerClientTest {
+
+    private val connection = LocalConnection()
+    private val client = TestBrokerClient(connection)
+
+    @Test
+    fun `test greeting RPC`() {
+        runBlocking {
+            val response = client.greetingRpc.call(GreetingRequest("Beemo"))
+            Assertions.assertEquals("Hello, Beemo", response.value.greeting)
+        }
+    }
+
+    @Test
+    fun `test null RPC`() {
+        runBlocking {
+            val response = client.nullRpc.call(null)
+            Assertions.assertNull(response.value)
+        }
+    }
+
+}

latte/src/test/kotlin/gg/beemo/latte/broker/TestBrokerClient.kt

@@ -0,0 +1,34 @@
+package gg.beemo.latte.broker
+
+import com.squareup.moshi.JsonClass
+import kotlinx.coroutines.delay
+import kotlin.time.Duration.Companion.seconds
+
+
+@JsonClass(generateAdapter = true)
+data class GreetingRequest(val name: String)
+
+@JsonClass(generateAdapter = true)
+data class GreetingResponse(val greeting: String)
+
+class TestBrokerClient(connection: BrokerConnection) : BrokerClient(connection) {
+
+    val greetingRpc = rpc<GreetingRequest, GreetingResponse>(
+        topic = "rpc.greetings",
+        key = "greeting.requests",
+    ) {
+        delay(2.seconds)
+        return@rpc GreetingResponse("Hello, ${it.value.name}")
+    }
+
+    val nullRpc = rpc<Unit?, Unit?>(
+        topic = "null",
+        key = "null",
+    ) {
+        if (it.value != null) {
+            throw IllegalStateException("nullRpc received non-null")
+        }
+        return@rpc null
+    }
+
+}