refactor(middleware): read and respond request

Author: 1zun4

src/main/kotlin/net/ccbluex/netty/http/HttpServerHandler.kt

@@ -68,9 +68,13 @@ internal class HttpServerHandler(private val server: HttpServer) : ChannelInboun
                 if (connection.equals("Upgrade", ignoreCase = true) &&
                     upgrade.equals("WebSocket", ignoreCase = true)) {
 
-                    if (server.middlewares.any {
-                        it is Middleware.OnWebSocketUpgrade && !it.invoke(ctx, msg)
-                    }) return
+                    server.middlewares.filterIsInstance<Middleware.OnWebSocketUpgrade>().forEach { middleware ->
+                        val response = middleware.invoke(ctx, msg)
+                        if (response != null) {
+                            ctx.writeAndFlush(response)
+                            return
+                        }
+                    }
 
                     // Takes out Http Request Handler from the pipeline and replaces it with WebSocketHandler
                     ctx.pipeline().replace(this, "websocketHandler", WebSocketHandler(server))
@@ -95,11 +99,7 @@ internal class HttpServerHandler(private val server: HttpServer) : ChannelInboun
                         URLDecoder.decode(msg.uri(), Charsets.UTF_8),
                         msg.headers().associate { it.key to it.value },
                     )
-
-                    if (server.middlewares.any {
-                        it is Middleware.OnRequestStart && !it.invoke(ctx, msg, requestContext)
-                    }) return
-
+                    
                     localRequestContext.set(requestContext)
                 }
             }
@@ -119,12 +119,17 @@ internal class HttpServerHandler(private val server: HttpServer) : ChannelInboun
                 if (msg is LastHttpContent) {
                     localRequestContext.remove()
 
-                    var response = server.processRequestContext(requestContext)
-                    server.middlewares.forEach {
-                        if (it is Middleware.OnFullHttpResponse) {
-                            response = it.invoke(requestContext, response)
+                    server.middlewares.filterIsInstance<Middleware.OnRequest>().forEach { middleware ->
+                        val response = middleware.invoke(requestContext)
+                        if (response != null) {
+                            ctx.writeAndFlush(response)
+                            return
                         }
                     }
+                    var response = server.processRequestContext(requestContext)
+                    server.middlewares.filterIsInstance<Middleware.OnResponse>().forEach { middleware ->
+                        response = middleware.invoke(requestContext, response)
+                    }
                     ctx.writeAndFlush(response)
                 }
             }

src/main/kotlin/net/ccbluex/netty/http/middleware/CorsMiddleware.kt

@@ -24,7 +24,7 @@ class CorsMiddleware(
         listOf("GET", "POST", "PUT", "DELETE", "PATCH", "HEAD", "OPTIONS"),
     private val allowedHeaders: List<String> =
         listOf("Content-Type", "Content-Length", "Authorization", "Accept", "X-Requested-With")
-): Middleware.OnFullHttpResponse {
+): Middleware.OnResponse {
 
     /**
      * Middleware to handle CORS requests.

src/main/kotlin/net/ccbluex/netty/http/middleware/Middleware.kt

@@ -27,19 +27,19 @@ import net.ccbluex.netty.http.model.RequestContext
 sealed interface Middleware {
     fun interface OnWebSocketUpgrade : Middleware {
         /**
-         * @return if it's accepted
+         * @return null, when accepted.
          */
-        operator fun invoke(ctx: ChannelHandlerContext, request: HttpRequest): Boolean
+        operator fun invoke(ctx: ChannelHandlerContext, request: HttpRequest): FullHttpResponse?
     }
 
-    fun interface OnRequestStart : Middleware {
+    fun interface OnRequest : Middleware {
         /**
-         * @return if it's accepted
+         * @return null, to continue processing the request.
          */
-        operator fun invoke(ctx: ChannelHandlerContext, request: HttpRequest, requestContext: RequestContext): Boolean
+        operator fun invoke(context: RequestContext): FullHttpResponse?
     }
 
-    fun interface OnFullHttpResponse : Middleware {
+    fun interface OnResponse : Middleware {
         operator fun invoke(context: RequestContext, response: FullHttpResponse): FullHttpResponse
     }
 }

src/test/kotlin/HttpMiddlewareServerTest.kt

@@ -65,7 +65,7 @@ class HttpMiddlewareServerTest {
             get("/", ::static)
         }
 
-        server.middleware(Middleware.OnFullHttpResponse { requestContext, fullHttpResponse ->
+        server.middleware(Middleware.OnResponse { requestContext, fullHttpResponse ->
             // Add custom headers to the response
             fullHttpResponse.headers().add("X-Custom-Header", "Custom Value")
 
@@ -77,11 +77,7 @@ class HttpMiddlewareServerTest {
 
             fullHttpResponse
         }).middleware(Middleware.OnWebSocketUpgrade { context, _ ->
-            context.writeAndFlush(
-                httpBadRequest("WebSocket unsupported")
-            )
-
-            false
+            httpBadRequest("WebSocket unsupported")
         })
 
         server.start(8080)  // Start the server on port 8080