pom.xml

@@ -52,7 +52,7 @@
         <dependency>
             <groupId>io.undertow</groupId>
             <artifactId>undertow-core</artifactId>
-            <version>2.2.22.Final</version>
+            <version>2.3.5.Final</version>
         </dependency>
         <dependency>
             <groupId>org.junit.jupiter</groupId>

src/main/java/ch/fritteli/labyrinth/server/LabyrinthServer.java

@@ -1,48 +1,51 @@
 package ch.fritteli.labyrinth.server;
 
 import ch.fritteli.labyrinth.server.handler.CreateHandler;
-import ch.fritteli.labyrinth.server.handler.LanyrinthRenderHandler;
+import ch.fritteli.labyrinth.server.handler.RenderHandler;
 import io.undertow.Undertow;
 import io.undertow.server.RoutingHandler;
-import io.undertow.util.StatusCodes;
 import io.vavr.control.Try;
 import lombok.NonNull;
 import lombok.extern.slf4j.Slf4j;
 
-import java.net.InetSocketAddress;
-
 @Slf4j
 public class LabyrinthServer {
+    @NonNull
+    private final ServerConfig config;
     @NonNull
     private final Undertow undertow;
 
     private LabyrinthServer(@NonNull final ServerConfig config) {
-        log.info("Starting Server at http://{}:{}/", config.getAddress().getHostAddress(), config.getPort());
+        this.config = config;
-        final RoutingHandler routingHandler = new RoutingHandler().get(CreateHandler.PATH_TEMPLATE, new CreateHandler())
+        final String hostAddress = config.getAddress().getHostAddress();
-                .post("/render", new LanyrinthRenderHandler())
+        final int port = config.getPort();
-                .setFallbackHandler(exchange -> exchange.setStatusCode(
+        log.info("Starting Server at http://{}:{}/", hostAddress, port);
-                                StatusCodes.NOT_FOUND)
+        final RoutingHandler routingHandler = new RoutingHandler()
-                        .getResponseSender()
+                .get(CreateHandler.PATH_TEMPLATE, new CreateHandler())
-                        .send("Resource %s not found".formatted(
+                .post("/render", new RenderHandler());
-                                exchange.getRequestURI())));
+
         this.undertow = Undertow.builder()
-                .addHttpListener(config.getPort(), config.getAddress().getHostAddress())
+                .addHttpListener(port, hostAddress)
                 .setHandler(routingHandler)
                 .build();
     }
 
+    @NonNull
     public static Try<LabyrinthServer> createAndStartServer() {
-        final Try<LabyrinthServer> serverOption = Try.of(ServerConfig::init).mapTry(LabyrinthServer::new);
+        return Try.of(ServerConfig::init)
-        serverOption.forEach(LabyrinthServer::start);
+                .flatMapTry(LabyrinthServer::createAndStartServer);
-        return serverOption;
+    }
+
+    @NonNull
+    public static Try<LabyrinthServer> createAndStartServer(@NonNull final ServerConfig config) {
+        return Try.of(() -> new LabyrinthServer(config))
+                .peek(LabyrinthServer::start);
     }
 
     private void start() {
         Runtime.getRuntime().addShutdownHook(new Thread(this::stop, "listener-stopper"));
         this.undertow.start();
-        Try.of(() -> (InetSocketAddress) this.undertow.getListenerInfo().get(0).getAddress())
+        log.info("Listeing on http://{}:{}", this.config.getAddress().getHostAddress(), this.config.getPort());
-                .onFailure(e -> log.warn("Started server, unable to determine listeing address/port."))
-                .forEach(address -> log.info("Listening on http://{}:{}", address.getHostString(), address.getPort()));
     }
 
     private void stop() {
@@ -51,110 +54,6 @@ public class LabyrinthServer {
         log.info("Server stopped.");
     }
 
-//    private void handleCreate(HttpExchange exchange) {
-//        this.executorService.submit(() -> {
-//            log.debug("Handling request to {}", exchange.getRequestURI());
-//            try {
-//                final String requestMethod = exchange.getRequestMethod();
-//                if (!requestMethod.equals("GET")) {
-//                    exchange.getResponseBody().close();
-//                    exchange.sendResponseHeaders(405, -1);
-//                    return;
-//                }
-//                final Map<RequestParameter, String> requestParams = this.parseQueryString(exchange.getRequestURI()
-//                                                                                                  .getQuery());
-//                final int width = this.getOrDefault(requestParams.get(RequestParameter.WIDTH), Integer::valueOf, 5);
-//                final int height = this.getOrDefault(requestParams.get(RequestParameter.HEIGHT), Integer::valueOf, 7);
-//                final Option<Long> idOption = requestParams.get(RequestParameter.ID)
-//                                                           .toTry()
-//                                                           .map(Long::valueOf)
-//                                                           .toOption();
-//                final Option<OutputType> outputOption = requestParams.get(RequestParameter.OUTPUT)
-//                                                                     .flatMap(OutputType::ofString);
-//                final Headers responseHeaders = exchange.getResponseHeaders();
-//                final AtomicBoolean needsRedirect = new AtomicBoolean(false);
-//                final long id = idOption.onEmpty(() -> needsRedirect.set(true)).getOrElse(System::nanoTime);
-//                final OutputType output = outputOption.onEmpty(() -> needsRedirect.set(true))
-//                                                      .getOrElse(OutputType.HTML);
-//                if (needsRedirect.get()) {
-//                    responseHeaders.add("Location",
-//                                        "create?width=" + width + "&height=" + height + "&output=" + output
-//                                        .toString() +
-//                                        "&id=" + id
-//                    );
-//                    exchange.sendResponseHeaders(302, -1);
-//                    return;
-//                }
-//                final byte[] render;
-//                try {
-//                    final Labyrinth labyrinth = new Labyrinth(width, height, id);
-//                    render = output.render(labyrinth);
-//                } catch (Exception e) {
-//                    responseHeaders.add("Content-type", "text/plain; charset=UTF-8");
-//                    exchange.sendResponseHeaders(500, 0);
-//                    final OutputStream responseBody = exchange.getResponseBody();
-//                    responseBody.write(("Error: " + e.getMessage()).getBytes(StandardCharsets.UTF_8));
-//                    responseBody.flush();
-//                    return;
-//                }
-//                responseHeaders.add("Content-type", output.getContentType());
-//                if (output.isAttachment()) {
-//                    responseHeaders.add("Content-disposition", String.format(
-//                            "attachment; filename=\"labyrinth-%dx%d-%d.%s\"",
-//                            width,
-//                            height,
-//                            id,
-//                            output.getFileExtension()
-//                    ));
-//                }
-//                exchange.sendResponseHeaders(200, 0);
-//                final OutputStream responseBody = exchange.getResponseBody();
-//                responseBody.write(render);
-//                responseBody.flush();
-//            } catch (Exception e) {
-//                log.error("FSCK!", e);
-//            } finally {
-//                exchange.close();
-//            }
-//        });
-//    }
-
-//    @NonNull
-//    private Map<RequestParameter, String> parseQueryString(@Nullable final String query) {
-//        if (query == null) {
-//            return HashMap.empty();
-//        }
-//        HashMap<RequestParameter, String> result = HashMap.empty();
-//        final String[] parts = query.split("&");
-//        for (final String part : parts) {
-//            final int split = part.indexOf('=');
-//            if (split == -1) {
-//                final Try<RequestParameter> tryKey = Try.of(() -> this.normalizeParameterName(part));
-//                if (tryKey.isSuccess()) {
-//                    result = result.put(tryKey.get(), null);
-//                }
-//            } else {
-//                final String key = part.substring(0, split);
-//                final String value = part.substring(split + 1);
-//                final Try<RequestParameter> tryKey = Try.of(() -> this.normalizeParameterName(key));
-//                if (tryKey.isSuccess()) {
-//                    result = result.put(tryKey.get(), value);
-//                }
-//            }
-//        }
-//        return result;
-//    }
-
-//    private RequestParameter normalizeParameterName(final String paramName) {
-//        return RequestParameter.parseName(paramName).get();
-//    }
-
-//    private <T> T getOrDefault(@NonNull final Option<String> input,
-//                               @NonNull final Function<String, T> mapper,
-//                               @Nullable final T defaultValue) {
-//        return input.toTry().map(mapper).getOrElse(defaultValue);
-//    }
-
 //    private void handleRender(final HttpExchange exchange) {
 //        this.executorService.submit(() -> {
 //            try {
@@ -198,23 +97,4 @@ public class LabyrinthServer {
 //            }
 //        });
 //    }
-
-//    private enum RequestParameter {
-//        WIDTH("w", "width"),
-//        HEIGHT("h", "height"),
-//        ID("i", "id"),
-//        OUTPUT("o", "output");
-//        private final Set<String> names;
-//
-//        RequestParameter(@NonNull final String... names) {
-//            this.names = HashSet.of(names);
-//        }
-//
-//        static Option<RequestParameter> parseName(@Nullable final String name) {
-//            if (name == null) {
-//                return Option.none();
-//            }
-//            return Stream.of(values()).find(param -> param.names.exists(name::equalsIgnoreCase));
-//        }
-//    }
 }

src/main/java/ch/fritteli/labyrinth/server/Main.java

@@ -5,6 +5,7 @@ import lombok.extern.slf4j.Slf4j;
 @Slf4j
 public class Main {
     public static void main(String[] args) {
-        LabyrinthServer.createAndStartServer().onFailure(e -> log.error("Failed to create server. Stopping.", e));
+        LabyrinthServer.createAndStartServer()
+                .onFailure(e -> log.error("Failed to create server. Stopping.", e));
     }
 }

src/main/java/ch/fritteli/labyrinth/server/OutputType.java

@@ -17,38 +17,51 @@ import java.util.function.Function;
 
 public enum OutputType {
     TEXT_PLAIN("text/plain; charset=UTF-8",
-            labyrinth -> TextRenderer.newInstance().render(labyrinth).getBytes(StandardCharsets.UTF_8),
             "txt",
+            labyrinth -> TextRenderer.newInstance().render(labyrinth).getBytes(StandardCharsets.UTF_8),
             false,
             "t",
-            "text"
+            "text"),
-    ),
     HTML("text/html",
-            labyrinth -> HTMLRenderer.newInstance().render(labyrinth).getBytes(StandardCharsets.UTF_8),
             "html",
+            labyrinth -> HTMLRenderer.newInstance().render(labyrinth).getBytes(StandardCharsets.UTF_8),
             false,
             "h",
-            "html"
+            "html"),
-    ),
+    PDF("application/pdf",
-    PDF("application/pdf", labyrinth -> PDFRenderer.newInstance().render(labyrinth), "pdf", false, "p", "pdf"),
+            "pdf",
-    PDFFILE("application/pdf", labyrinth -> PDFRenderer.newInstance().render(labyrinth), "pdf", true, "f", "pdffile"),
+            labyrinth -> PDFRenderer.newInstance().render(labyrinth),
-    BINARY("application/octet-stream", SerializerDeserializer::serialize, "laby", true, "b", "binary");
+            false,
+            "p",
+            "pdf"),
+    PDFFILE("application/pdf",
+            "pdf",
+            labyrinth -> PDFRenderer.newInstance().render(labyrinth),
+            true,
+            "f",
+            "pdffile"),
+    BINARY("application/octet-stream",
+            "laby",
+            SerializerDeserializer::serialize,
+            true,
+            "b",
+            "binary");
     @Getter
     @NonNull
     private final String contentType;
+    @Getter
     @NonNull
-    private final List<String> names;
+    private final String fileExtension;
     @NonNull
     private final Function<Labyrinth, byte[]> render;
     @Getter
     private final boolean attachment;
-    @Getter
     @NonNull
-    private final String fileExtension;
+    private final List<String> names;
 
     OutputType(@NonNull final String contentType,
-               @NonNull final Function<Labyrinth, byte[]> render,
                @NonNull final String fileExtension,
+               @NonNull final Function<Labyrinth, byte[]> render,
                final boolean attachment,
                @NonNull final String... names) {
         this.contentType = contentType;
@@ -58,20 +71,23 @@ public enum OutputType {
         this.names = List.of(names);
     }
 
+    @NonNull
     public static Option<OutputType> ofString(@Nullable final String name) {
-        if (name == null) {
+        return Option.of(name)
-            return Option.none();
+                .map(String::toLowerCase)
-        }
+                .flatMap(nameLC -> Stream.of(values())
-        final String nameLC = name.toLowerCase();
+                        .find(param -> param.names.contains(nameLC)));
-        return Stream.of(values()).find(param -> param.names.contains(nameLC));
+
     }
 
+    @NonNull
     @Override
     public String toString() {
         return this.names.last();
     }
 
-    public byte[] render(@NonNull final Labyrinth labyrinth) {
+    @NonNull
+    public byte[] render(@NonNull final Labyrinth labyrinth) throws Exception {
         return this.render.apply(labyrinth);
     }
 }

src/main/java/ch/fritteli/labyrinth/server/ServerConfig.java

@@ -17,7 +17,8 @@ public class ServerConfig {
     public static final String SYSPROP_HOST = "fritteli.labyrinth.server.host";
     public static final String SYSPROP_PORT = "fritteli.labyrinth.server.port";
 
-    @NonNull InetAddress address;
+    @NonNull
+    InetAddress address;
     int port;
 
     public ServerConfig(@Nullable final String address, final int port) throws ConfigurationException {
@@ -26,19 +27,6 @@ public class ServerConfig {
         log.debug("host={}, port={}", this.address, this.port);
     }
 
-    @NonNull
-    private static InetAddress validateAddress(@Nullable final String address) {
-        return Try.of(() -> InetAddress.getByName(address))
-                .getOrElseThrow(cause -> new ConfigurationException("Invalid hostname/address: " + address, cause));
-    }
-
-    private static int validatePort(final int port) {
-        if (port < 0 || port > 0xFFFF) {
-            throw new ConfigurationException("Port out of range (0..65535): " + port);
-        }
-        return port;
-    }
-
     @NonNull
     public static ServerConfig init() throws ConfigurationException {
         final String host = System.getProperty(SYSPROP_HOST);
@@ -47,15 +35,30 @@ public class ServerConfig {
         return new ServerConfig(host, port);
     }
 
+    @NonNull
+    private static InetAddress validateAddress(@Nullable final String address) {
+        return Try.of(() -> InetAddress.getByName(address))
+                .getOrElseThrow(cause -> new ConfigurationException(
+                        "Invalid hostname/address: %s".formatted(address),
+                        cause
+                ));
+    }
+
+    private static int validatePort(final int port) {
+        if (port < 0 || port > 0xFFFF) {
+            throw new ConfigurationException("Port out of range (0..65535): %s".formatted(port));
+        }
+        return port;
+    }
+
     private static int validatePort(@Nullable final String portString) {
         if (portString == null) {
             log.info("No port configured; using default.");
             return 0;
         }
         return Try.of(() -> Integer.valueOf(portString))
-                .map(ServerConfig::validatePort)
                 .getOrElseThrow(cause -> new ConfigurationException(
-                        "Failed to parse port specified in system property '" + SYSPROP_PORT + "': " + portString,
+                        "Failed to parse port specified in system property '%s': %s".formatted(SYSPROP_PORT, portString),
                         cause
                 ));
     }

src/main/java/ch/fritteli/labyrinth/server/handler/AbstractHttpHandler.java

@@ -5,12 +5,17 @@ import io.undertow.server.HttpServerExchange;
 import io.undertow.util.StatusCodes;
 import lombok.NonNull;
 import lombok.extern.slf4j.Slf4j;
+import org.slf4j.MDC;
+
+import java.util.UUID;
 
 @Slf4j
 public abstract class AbstractHttpHandler implements HttpHandler {
     @Override
-    public final void handleRequest(final HttpServerExchange exchange) {
+    public final void handleRequest(@NonNull final HttpServerExchange exchange) {
+        try (final MDC.MDCCloseable mdc = MDC.putCloseable("correlationId", UUID.randomUUID().toString())) {
             if (exchange.isInIoThread()) {
+                log.debug("Dispatching request");
                 exchange.dispatch(this);
                 return;
             }
@@ -23,6 +28,7 @@ public abstract class AbstractHttpHandler implements HttpHandler {
                         .send(StatusCodes.INTERNAL_SERVER_ERROR_STRING);
             }
         }
+    }
 
     protected abstract void handle(@NonNull final HttpServerExchange exchange) throws Exception;
 }

src/main/java/ch/fritteli/labyrinth/server/handler/CreateHandler.java

@@ -14,11 +14,15 @@ import io.vavr.control.Try;
 import lombok.NonNull;
 import lombok.extern.slf4j.Slf4j;
 import org.jetbrains.annotations.Nullable;
+import org.slf4j.MDC;
 
 import java.nio.ByteBuffer;
+import java.time.Instant;
+import java.time.temporal.ChronoUnit;
 import java.util.Deque;
 import java.util.Map;
 import java.util.Random;
+import java.util.UUID;
 
 @Slf4j
 public class CreateHandler extends AbstractHttpHandler {
@@ -26,19 +30,34 @@ public class CreateHandler extends AbstractHttpHandler {
 
     @Override
     protected void handle(@NonNull final HttpServerExchange exchange) {
+        final Instant start = Instant.now();
+        log.debug("Handling create request");
         this.createLabyrinthFromRequestParameters(exchange.getQueryParameters())
                 .onFailure(e -> {
+                    log.error("Error creating Labyrinth from request", e);
                     exchange.setStatusCode(StatusCodes.INTERNAL_SERVER_ERROR);
-                    exchange.setReasonPhrase(e.getMessage());
+                    exchange.setReasonPhrase(StatusCodes.INTERNAL_SERVER_ERROR_STRING);
-                }).forEach(tuple -> {
+                })
+                .forEach(tuple -> {
                     final OutputType outputType = tuple._1();
                     final Labyrinth labyrinth = tuple._2();
-                    final byte[] bytes = outputType.render(labyrinth);
+                    final byte[] bytes;
-                    exchange.getResponseHeaders().put(Headers.CONTENT_TYPE, outputType.getContentType());
+                    try {
-                    exchange.getResponseHeaders().put(HttpString.tryFromString("X-Labyrinth-ID"), String.valueOf(labyrinth.getRandomSeed()));
+                        bytes = outputType.render(labyrinth);
-                    exchange.getResponseHeaders().put(HttpString.tryFromString("X-Labyrinth-Width"), String.valueOf(labyrinth.getWidth()));
+                    } catch (@NonNull final Exception e) {
-                    exchange.getResponseHeaders().put(HttpString.tryFromString("X-Labyrinth-Height"), String.valueOf(labyrinth.getHeight()));
+                        log.error("Error rendering Labyrinth", e);
+                        exchange.setStatusCode(StatusCodes.INTERNAL_SERVER_ERROR);
+                        exchange.setReasonPhrase(StatusCodes.INTERNAL_SERVER_ERROR_STRING);
+                        return;
+                    }
+                    exchange.getResponseHeaders()
+                            .put(Headers.CONTENT_TYPE, outputType.getContentType())
+                            .put(HttpString.tryFromString("X-Labyrinth-ID"), String.valueOf(labyrinth.getRandomSeed()))
+                            .put(HttpString.tryFromString("X-Labyrinth-Width"), String.valueOf(labyrinth.getWidth()))
+                            .put(HttpString.tryFromString("X-Labyrinth-Height"), String.valueOf(labyrinth.getHeight()))
+                            .put(HttpString.tryFromString("X-Labyrinth-Generation-Duration-millis"), String.valueOf(start.until(Instant.now(), ChronoUnit.MILLIS)));
                     exchange.getResponseSender().send(ByteBuffer.wrap(bytes));
+                    log.debug("Create request handled.");
                 });
     }
 
@@ -73,13 +92,24 @@ public class CreateHandler extends AbstractHttpHandler {
             });
         }
 
-        @NonNull Try<Tuple2<OutputType, Labyrinth>> createLabyrinth() {
+        @NonNull
-            final Option<OutputType> output = getParameterValues(RequestParameter.OUTPUT).foldLeft(Option.none(), (type, param) -> type.orElse(() -> OutputType.ofString(param)));
+        Try<Tuple2<OutputType, Labyrinth>> createLabyrinth() {
-            final Option<Integer> width = getParameterValues(RequestParameter.WIDTH).foldLeft(Option.none(), (value, param) -> value.orElse(() -> Try.of(() -> Integer.parseInt(param)).toOption()));
+            final Option<OutputType> output = getParameterValues(RequestParameter.OUTPUT)
-            final Option<Integer> height = getParameterValues(RequestParameter.HEIGHT).foldLeft(Option.none(), (value, param) -> value.orElse(() -> Try.of(() -> Integer.parseInt(param)).toOption()));
+                    .foldLeft(Option.none(), (type, param) -> type.orElse(() -> OutputType.ofString(param)));
-            final Option<Long> id = getParameterValues(RequestParameter.ID).foldLeft(Option.none(), (value, param) -> value.orElse(() -> Try.of(() -> Long.parseLong(param)).toOption()));
+            final Option<Integer> width = getParameterValues(RequestParameter.WIDTH)
+                    .foldLeft(Option.none(), (value, param) -> value.orElse(() -> Try.of(() -> Integer.parseInt(param)).toOption()));
+            final Option<Integer> height = getParameterValues(RequestParameter.HEIGHT)
+                    .foldLeft(Option.none(), (value, param) -> value.orElse(() -> Try.of(() -> Integer.parseInt(param)).toOption()));
+            final Option<Long> id = getParameterValues(RequestParameter.ID)
+                    .foldLeft(Option.none(), (value, param) -> value.orElse(() -> Try.of(() -> Long.parseLong(param)).toOption()));
 
-            return Try.of(() -> Tuple.of(output.get(), new Labyrinth(width.get(), height.get(), id.getOrElse(() -> new Random().nextLong()))));
+            return Try.of(() -> {
+                final OutputType t1 = output.get();
+                final Integer width1 = width.get();
+                final Integer height1 = height.get();
+                final Long orElse = id.getOrElse(() -> new Random().nextLong());
+                return Tuple.of(t1, new Labyrinth(width1, height1, orElse));
+            });
         }
 
         @NonNull

src/main/java/ch/fritteli/labyrinth/server/handler/RenderHandler.java

@@ -4,7 +4,7 @@ import io.undertow.server.HttpHandler;
 import io.undertow.server.HttpServerExchange;
 import io.undertow.util.StatusCodes;
 
-public class LanyrinthRenderHandler implements HttpHandler {
+public class RenderHandler implements HttpHandler {
     @Override
     public void handleRequest(final HttpServerExchange exchange) {
         if (exchange.isInIoThread()) {

src/main/resources/logback.xml

@@ -6,7 +6,7 @@
         <!-- encoders are by default assigned the type
         ch.qos.logback.classic.encoder.PatternLayoutEncoder -->
         <encoder>
-            <pattern>%d{HH:mm:ss.SSS} [%thread] %-5level %logger{36} - %msg%n</pattern>
+            <pattern>%d{HH:mm:ss.SSS} %-5level %X{correlationId} [%thread] %logger{36} - %msg%n</pattern>
         </encoder>
     </appender>