From 41995979e129295ccf8df896b4260587f85ad9b5 Mon Sep 17 00:00:00 2001 From: Manuel Friedli Date: Tue, 6 Oct 2020 02:09:03 +0200 Subject: [PATCH] Add simple Server. --- labyrinth-server.iml | 8 + pom.xml | 19 +- .../labyrinth/server/LabyrinthServer.java | 198 ++++++++++++++++++ .../ch/fritteli/labyrinth/server/Main.java | 8 + 4 files changed, 232 insertions(+), 1 deletion(-) create mode 100644 src/main/java/ch/fritteli/labyrinth/server/LabyrinthServer.java create mode 100644 src/main/java/ch/fritteli/labyrinth/server/Main.java diff --git a/labyrinth-server.iml b/labyrinth-server.iml index e34c156..fd372d5 100644 --- a/labyrinth-server.iml +++ b/labyrinth-server.iml @@ -12,5 +12,13 @@ + + + + + + + + \ No newline at end of file diff --git a/pom.xml b/pom.xml index 5967c56..28f3f51 100644 --- a/pom.xml +++ b/pom.xml @@ -13,6 +13,23 @@ ch.fritteli.labyrinth labyrinth-server 0.0.1-SNAPSHOT + + + + ch.fritteli.labyrinth + labyrinth-generator + 0.0.1 + + + io.vavr + vavr + + + org.projectlombok + lombok + + + @@ -20,7 +37,7 @@ - ch.fritteli.labyrinth.Main + ch.fritteli.labyrinth.server.Main diff --git a/src/main/java/ch/fritteli/labyrinth/server/LabyrinthServer.java b/src/main/java/ch/fritteli/labyrinth/server/LabyrinthServer.java new file mode 100644 index 0000000..93fd8a1 --- /dev/null +++ b/src/main/java/ch/fritteli/labyrinth/server/LabyrinthServer.java @@ -0,0 +1,198 @@ +package ch.fritteli.labyrinth.server; + +import ch.fritteli.labyrinth.generator.model.Labyrinth; +import ch.fritteli.labyrinth.generator.renderer.html.HTMLRenderer; +import ch.fritteli.labyrinth.generator.renderer.pdf.PDFRenderer; +import ch.fritteli.labyrinth.generator.renderer.text.TextRenderer; +import com.sun.net.httpserver.Headers; +import com.sun.net.httpserver.HttpServer; +import io.vavr.collection.HashMap; +import io.vavr.collection.HashSet; +import io.vavr.collection.List; +import io.vavr.collection.Map; +import io.vavr.collection.Set; +import io.vavr.collection.Stream; +import io.vavr.control.Option; +import io.vavr.control.Try; +import lombok.Getter; +import lombok.NonNull; +import org.jetbrains.annotations.Nullable; + +import java.io.IOException; +import java.io.OutputStream; +import java.net.InetSocketAddress; +import java.nio.charset.StandardCharsets; +import java.util.function.Function; + +public class LabyrinthServer { + + private final HttpServer httpServer; + + public LabyrinthServer(final int port) throws IOException { + this.httpServer = HttpServer.create(new InetSocketAddress(port), 0); + this.httpServer.createContext("/create", exchange -> { + final String requestMethod = exchange.getRequestMethod(); + if (!requestMethod.equals("GET")) { + exchange.getResponseBody().close(); + exchange.sendResponseHeaders(405, -1); + exchange.close(); + return; + } + final Map requestParams = this.parseQueryString(exchange.getRequestURI().getQuery()); + final int width = this.getOrDefault(requestParams.get(RequestParameter.WIDTH), Integer::valueOf, 1); + final int height = this.getOrDefault(requestParams.get(RequestParameter.HEIGHT), Integer::valueOf, 1); + final Option seedOption = requestParams.get(RequestParameter.ID).toTry().map(Long::valueOf).toOption(); + final long seed; + final Option outputOption = requestParams.get(RequestParameter.OUTPUT).flatMap(OutputType::ofString); + final OutputType output; + final Headers responseHeaders = exchange.getResponseHeaders(); + boolean needsRedirect = false; + if (seedOption.isEmpty()) { + needsRedirect = true; + seed = System.nanoTime(); + } else { + seed = seedOption.get(); + } + if (outputOption.isEmpty()) { + needsRedirect = true; + output = OutputType.HTML; + } else { + output = outputOption.get(); + } + if (needsRedirect) { + responseHeaders.add("Location", "/create?width=" + width + "&height=" + height + "&output=" + output.toString() + "&id=" + seed); + exchange.sendResponseHeaders(302, -1); + exchange.close(); + return; + } + responseHeaders.add("Content-type", output.getContentType()); + exchange.sendResponseHeaders(200, 0); + final Labyrinth labyrinth = new Labyrinth(width, height, seed); + final byte[] render = output.render(labyrinth); + final OutputStream responseBody = exchange.getResponseBody(); + responseBody.write(render); + responseBody.flush(); + exchange.close(); + }); + } + + public static Option createListener() { + final String listenerPort = System.getProperty("fritteli.labyrinth.listenerport"); + final Option listenerOption = Option.of(listenerPort) + .toTry() + .map(Integer::valueOf) + .onFailure(cause -> System.err.println("Invalid port specified via system property 'fritteli.labyrinth.listenerport': " + + listenerPort + + ". Not starting webserver.")) + .mapTry(LabyrinthServer::new) + .onFailure(cause -> System.err.println("Failed to create Listener: " + cause)) + .toOption(); + listenerOption.forEach(LabyrinthServer::start); + return listenerOption; + } + + private T getOrDefault(@NonNull final Option input, @NonNull final Function mapper, @Nullable final T defaultValue) { + return input.toTry().map(mapper).getOrElse(defaultValue); + } + + @NonNull + private Map parseQueryString(@Nullable final String query) { + if (query == null) { + return HashMap.empty(); + } + HashMap result = HashMap.empty(); + final String[] parts = query.split("&"); + for (final String part : parts) { + final int split = part.indexOf('='); + if (split == -1) { + final Try 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 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(); + } + + public void start() { + Runtime.getRuntime().addShutdownHook(new Thread(this::stop, "listener-stopper")); + this.httpServer.start(); + System.out.println("Listening on " + this.httpServer.getAddress()); + } + + public void stop() { + System.out.println("Stopping listener ..."); + this.httpServer.stop(5); + System.out.println("Listener stopped."); + } + + private enum RequestParameter { + WIDTH("w", "width"), + HEIGHT("h", "height"), + ID("i", "id"), + OUTPUT("o", "output"); + private final Set names; + + RequestParameter(@NonNull final String... names) { + this.names = HashSet.of(names); + } + + static Option parseName(@Nullable final String name) { + if (name == null) { + return Option.none(); + } + final String nameLC = name.toLowerCase(); + return Stream.of(values()) + .find(param -> param.names.contains(nameLC)); + } + } + + private enum OutputType { + TEXT_PLAIN("text/plain; charset=UTF-8", labyrinth -> TextRenderer.newInstance().render(labyrinth).getBytes(StandardCharsets.UTF_8), "t", "text"), + HTML("text/html", labyrinth -> HTMLRenderer.newInstance().render(labyrinth).getBytes(StandardCharsets.UTF_8), "h", "html"), + PDF("application/pdf", labyrinth -> PDFRenderer.newInstance().render(labyrinth), "p", "pdf"); + @Getter + @NonNull + private final String contentType; + @NonNull + private final List names; + @NonNull + private final Function render; + + OutputType(@NonNull final String contentType, @NonNull final Function render, @NonNull final String... names) { + this.contentType = contentType; + this.render = render; + this.names = List.of(names); + } + + static Option ofString(@Nullable final String name) { + if (name == null) { + return Option.none(); + } + final String nameLC = name.toLowerCase(); + return Stream.of(values()) + .find(param -> param.names.contains(nameLC)); + + } + + @Override + public String toString() { + return this.names.last(); + } + + byte[] render(@NonNull final Labyrinth labyrinth) { + return this.render.apply(labyrinth); + } + } +} diff --git a/src/main/java/ch/fritteli/labyrinth/server/Main.java b/src/main/java/ch/fritteli/labyrinth/server/Main.java new file mode 100644 index 0000000..dd5e963 --- /dev/null +++ b/src/main/java/ch/fritteli/labyrinth/server/Main.java @@ -0,0 +1,8 @@ +package ch.fritteli.labyrinth.server; + +public class Main { + public static void main(String[] args) { + LabyrinthServer.createListener() + .onEmpty(() -> System.err.println("Failed to create server. Stopping.")); + } +}