Refactor SseIntegrationTest to use dynamic port assignment and simplify client/server initialization. (#212)

Author: devcrocod

kotlin-sdk-test/src/commonTest/kotlin/io/modelcontextprotocol/kotlin/sdk/integration/SseIntegrationTest.kt

@@ -1,7 +1,6 @@
 package io.modelcontextprotocol.kotlin.sdk.integration
 
 import io.ktor.client.HttpClient
-import io.ktor.client.plugins.sse.SSE
 import io.ktor.server.application.install
 import io.ktor.server.cio.CIOApplicationEngine
 import io.ktor.server.engine.EmbeddedServer
@@ -20,36 +19,32 @@ import kotlinx.coroutines.withContext
 import kotlin.test.Test
 import kotlin.test.fail
 import io.ktor.client.engine.cio.CIO as ClientCIO
+import io.ktor.client.plugins.sse.SSE as ClientSSE
 import io.ktor.server.cio.CIO as ServerCIO
+import io.ktor.server.sse.SSE as ServerSSE
+
+private const val URL = "127.0.0.1"
 
 class SseIntegrationTest {
     @Test
     fun `client should be able to connect to sse server`() = runTest {
         val serverEngine = initServer()
-        var client: Client? = null
         try {
             withContext(Dispatchers.Default) {
-                assertDoesNotThrow { client = initClient() }
+                val port = serverEngine.engine.resolvedConnectors().first().port
+                val client = initClient(port)
+                client.close()
             }
         } catch (e: Exception) {
             fail("Failed to connect client: $e")
         } finally {
-            client?.close()
             // Make sure to stop the server
             serverEngine.stopSuspend(1000, 2000)
         }
     }
 
-    private inline fun <T> assertDoesNotThrow(block: () -> T): T {
-        return try {
-            block()
-        } catch (e: Throwable) {
-            fail("Expected no exception, but got: $e")
-        }
-    }
-
-    private suspend fun initClient(): Client {
-        return HttpClient(ClientCIO) { install(SSE) }.mcpSse("http://$URL:$PORT")
+    private suspend fun initClient(port: Int): Client {
+        return HttpClient(ClientCIO) { install(ClientSSE) }.mcpSse("http://$URL:$port")
     }
 
     private suspend fun initServer(): EmbeddedServer<CIOApplicationEngine, CIOApplicationEngine.Configuration> {
@@ -58,16 +53,11 @@ class SseIntegrationTest {
             ServerOptions(capabilities = ServerCapabilities()),
         )
 
-        return embeddedServer(ServerCIO, host = URL, port = PORT) {
-            install(io.ktor.server.sse.SSE)
+        return embeddedServer(ServerCIO, host = URL, port = 0) {
+            install(ServerSSE)
             routing {
                 mcp { server }
             }
         }.startSuspend(wait = false)
     }
-
-    companion object {
-        private const val PORT = 3001
-        private const val URL = "localhost"
-    }
 }