1 files changed, 55 insertions, 2 deletions
diff --git a/src/main/scala/xyz/driver/core/app/DriverApp.scala b/src/main/scala/xyz/driver/core/app/DriverApp.scala
index 1ded4dd..ca3dd54 100644
--- a/src/main/scala/xyz/driver/core/app/DriverApp.scala
+++ b/src/main/scala/xyz/driver/core/app/DriverApp.scala
@@ -62,9 +62,59 @@ class DriverApp(
     }
   }
 
+  protected lazy val allowedCorsDomainSuffixes: Set[HttpOrigin] = {
+    import scala.collection.JavaConverters._
+    config
+      .getConfigList("application.cors.allowedOrigins")
+      .asScala
+      .map { c =>
+        HttpOrigin(c.getString("scheme"), Host(c.getString("hostSuffix")))
+      }(scala.collection.breakOut)
+  }
+
+  protected lazy val defaultCorsAllowedMethods: Set[HttpMethod] = {
+    import scala.collection.JavaConverters._
+    config.getStringList("application.cors.allowedMethods").asScala.toSet.flatMap(HttpMethods.getForKey)
+  }
+
+  protected lazy val defaultCorsAllowedOrigin: Origin = {
+    Origin(allowedCorsDomainSuffixes.to[collection.immutable.Seq])
+  }
+
+  protected def corsAllowedOriginHeader(origin: Option[Origin]): HttpHeader = {
+    val allowedOrigin =
+      origin
+        .filter { requestOrigin =>
+          allowedCorsDomainSuffixes.exists { allowedOriginSuffix =>
+            requestOrigin.origins.exists(o =>
+              o.scheme == allowedOriginSuffix.scheme &&
+                o.host.host.address.endsWith(allowedOriginSuffix.host.host.address()))
+          }
+        }
+        .getOrElse(defaultCorsAllowedOrigin)
+
+    `Access-Control-Allow-Origin`(HttpOriginRange(allowedOrigin.origins: _*))
+  }
+
+  protected def respondWithAllCorsHeaders: Directive0 = {
+    respondWithCorsAllowedHeaders tflatMap { _ =>
+      respondWithCorsAllowedMethodHeaders(defaultCorsAllowedMethods) tflatMap { _ =>
+        optionalHeaderValueByType[Origin](()) flatMap { origin =>
+          respondWithHeader(corsAllowedOriginHeader(origin))
+        }
+      }
+    }
+  }
+
   private def extractHeader(request: HttpRequest)(headerName: String): Option[String] =
     request.headers.find(_.name().toLowerCase === headerName).map(_.value())
 
+  protected def defaultOptionsRoute: Route = options {
+    respondWithAllCorsHeaders {
+      complete("OK")
+    }
+  }
+
   def appRoute: Route = {
     val serviceTypes   = modules.flatMap(_.routeTypes)
     val swaggerService = new Swagger(baseUrl, Scheme.forValue(scheme) :: Nil, version, serviceTypes, config, log)
@@ -75,7 +125,8 @@ class DriverApp(
       override def config: Config = self.config
       override def route: Route   = versionRt ~ healthRoute ~ swaggerRoute
     }
-    val combinedRoute = modules.map(_.route).foldLeft(basicRoutes.routeWithDefaults)(_ ~ _)
+    val combinedRoute =
+      Route.seal(modules.map(_.route).foldLeft(basicRoutes.routeWithDefaults)(_ ~ _) ~ defaultOptionsRoute)
 
     (extractHost & extractClientIP & trace(tracer)) {
       case (origin, ip) =>
@@ -97,7 +148,9 @@ class DriverApp(
                 .addHeader(RawHeader(ContextHeaders.TrackingIdHeader, trackingId))
                 .addHeader(RawHeader(ContextHeaders.StacktraceHeader, updatedStacktrace)))
 
-          combinedRoute(contextWithTrackingId)
+          respondWithAllCorsHeaders {
+            combinedRoute
+          }(contextWithTrackingId)
     }
   }