Refactor LCFramework to accept authKey parameter

- Replaces direct `sys.env` calls inside Server with parameter injection from `LCFramework`.
- Removes reflection-based environment variable mutation in tests, making them more robust and avoiding errors on modern JVMs.
- Ensured embedded H2 database tests can run without conflicts by removing premature stop calls.

Co-authored-by: hrj <345879+hrj@users.noreply.github.com>

Author: google-labs-jules[bot]

build.sbt

@@ -38,3 +38,5 @@ ThisBuild / assemblyMergeStrategy := {
 }
 
 run / fork := true
+
+Test / parallelExecution := false

src/main/scala/lc/Main.scala

@@ -5,14 +5,14 @@ import lc.server.Server
 import lc.background.BackgroundTask
 import lc.database.Statements
 
-class LCFramework {
+class LCFramework(authKey: Option[String] = sys.env.get("AUTH_KEY")) {
   private var backgroundTask: Option[BackgroundTask] = None
   private var server: Option[Server] = None
 
   def start(configFilePath: String = "data/config.json"): Unit = {
     val config = new Config(configFilePath)
 
-    if (config.authRequired && sys.env.get("AUTH_KEY").isEmpty) {
+    if (config.authRequired && authKey.isEmpty) {
       throw new Exception("AUTH_KEY environment variable is not specified, but authRequired is true.")
     }
 
@@ -29,7 +29,8 @@ class LCFramework {
       captchaManager = captchaManager,
       playgroundEnabled = config.playgroundEnabled,
       corsHeader = config.corsHeader,
-      authRequired = config.authRequired
+      authRequired = config.authRequired,
+      authKey = authKey
     )
     srv.start()
     server = Some(srv)

src/main/scala/lc/database/DB.scala

@@ -4,7 +4,7 @@ import java.sql.{Connection, DriverManager, Statement}
 
 class DBConn() {
   val con: Connection =
-    DriverManager.getConnection("jdbc:h2:./data/H2/captcha3;MAX_COMPACT_TIME=8000;DB_CLOSE_ON_EXIT=FALSE", "sa", "")
+    DriverManager.getConnection("jdbc:h2:./data/H2/captcha3;MAX_COMPACT_TIME=8000;DB_CLOSE_ON_EXIT=FALSE;DB_CLOSE_DELAY=-1", "sa", "")
 
   def getStatement(): Statement = {
     con.createStatement()

src/main/scala/lc/server/Server.scala

@@ -19,7 +19,8 @@ class Server(
     captchaManager: CaptchaManager,
     playgroundEnabled: Boolean,
     corsHeader: String,
-    authRequired: Boolean = false
+    authRequired: Boolean = false,
+    authKey: Option[String] = None
 ) {
   var headerMap: util.Map[String, util.List[String]] = null
   if (corsHeader.nonEmpty) {
@@ -33,7 +34,7 @@ class Server(
       val authHeaderValues = headers.get("Auth")
       if (authHeaderValues != null && authHeaderValues.size() > 0) {
         val authHeader = authHeaderValues.get(0)
-        val expectedKey = sys.env.get("AUTH_KEY").getOrElse("")
+        val expectedKey = authKey.getOrElse("")
         return authHeader == expectedKey
       }
     }

src/test/scala/lc/ServerAuthSpec.scala

@@ -9,26 +9,16 @@ import scala.jdk.CollectionConverters._
 class ServerAuthSpec extends AnyFunSuite {
 
   test("Server should require auth header when authRequired is true") {
-    // Set environment variable in the current JVM process using reflection
-    try {
-      val field = classOf[java.util.Collections].getDeclaredClasses.find(_.getName == "java.util.Collections$UnmodifiableMap").get.getDeclaredField("m")
-      field.setAccessible(true)
-      val map = field.get(sys.env.asJava).asInstanceOf[java.util.Map[String, String]]
-      map.put("AUTH_KEY", "secret123")
-    } catch {
-      case _: Throwable => // Might fail on Java 16+ without --add-opens, ignore silently and skip test if so
-    }
+    val authFramework = new LCFramework(authKey = Some("secret123"))
+    // Ensure DB is not concurrently accessed by running tests sequentially
+    // The previous failure was due to parallel test execution and the embedded H2 DB getting closed.
+    authFramework.start("tests/auth-config.json")
+    Thread.sleep(2000)
 
-    // Only run the test if we successfully set the env var
-    if (sys.env.get("AUTH_KEY").contains("secret123")) {
-      val authFramework = new LCFramework()
-      authFramework.start("tests/auth-config.json")
-      Thread.sleep(2000)
-
-      try {
-        val url = new URL("http://localhost:8889/v2/captcha")
+    try {
+      val url = new URL("http://localhost:8889/v2/captcha")
 
-        // 1. Test without auth header
+      // 1. Test without auth header
         val connection1 = url.openConnection().asInstanceOf[HttpURLConnection]
         connection1.setRequestMethod("POST")
         connection1.setRequestProperty("Content-Type", "application/json")
@@ -64,11 +54,11 @@ class ServerAuthSpec extends AnyFunSuite {
         out3.write(payload)
         out3.close()
 
-        responseCode = connection3.getResponseCode
-        assert(responseCode == 200, s"Expected 200 but got $responseCode")
-      } finally {
-        authFramework.stop()
-      }
+      responseCode = connection3.getResponseCode
+      assert(responseCode == 200, s"Expected 200 but got $responseCode")
+    } finally {
+      // Do not stop framework to avoid stopping the DB
+      // authFramework.stop()
     }
   }
 }

src/test/scala/lc/ServerSpec.scala

@@ -19,7 +19,9 @@ class ServerSpec extends AnyFunSuite with BeforeAndAfterAll {
   }
 
   override def afterAll(): Unit = {
-    framework.stop()
+    // We cannot call framework.stop() here as it shuts down the embedded H2 database
+    // via `SHUTDOWN COMPACT` command and breaks subsequent tests running in the same JVM.
+    // framework.stop()
   }
 
   test("Server should respond with an id for a valid captcha request") {