quick-e2e: Implement PaperDownloadService and configuration management for server file downloads

.gitignore

@@ -8,3 +8,5 @@ backend/src/main/resources/frontend
 backend/out
 logger/out
 sdks/java-sdk/out
+
+servers

tools/quick-e2e/build.gradle.kts

@@ -8,7 +8,7 @@ group = "de.oliver"
 description = "Tool to setup a complete environment for testing"
 
 java {
-    toolchain.languageVersion.set(JavaLanguageVersion.of(21))
+    toolchain.languageVersion.set(JavaLanguageVersion.of(23))
 }
 
 repositories {
@@ -42,7 +42,7 @@ tasks {
 
         // Set the release flag. This configures what version bytecode the compiler will emit, as well as what JDK APIs are usable.
         // See https://openjdk.java.net/jeps/247 for more information.
-        options.release.set(21)
+        options.release.set(23)
     }
 
     java {

tools/quick-e2e/src/main/java/de/oliver/quicke2e/Main.java

@@ -1,9 +1,23 @@
 package de.oliver.quicke2e;
 
+import de.oliver.quicke2e.config.Configuration;
+import de.oliver.quicke2e.paper.PaperDownloadService;
+
 public class Main {
 
     public static void main(String[] args) {
+        Configuration config = new Configuration(
+                "paper",
+                "1.21.4",
+                "latest",
+                new String[]{},
+                true,
+                new String[]{"OliverHD"},
+                "25565"
+        );
 
+        PaperDownloadService paper = new PaperDownloadService();
+        paper.downloadServerFile(config.type(), config.version(), config.build());
     }
 
 }

tools/quick-e2e/src/main/java/de/oliver/quicke2e/config/Configuration.java

@@ -0,0 +1,12 @@
+package de.oliver.quicke2e.config;
+
+public record Configuration(
+        String type,
+        String version,
+        String build,
+        String[] plugins,
+        boolean eula,
+        String[] opPlayers,
+        String port
+) {
+}

tools/quick-e2e/src/main/java/de/oliver/quicke2e/paper/BuildsResponse.java

@@ -0,0 +1,11 @@
+package de.oliver.quicke2e.paper;
+
+import com.google.gson.annotations.SerializedName;
+
+public record BuildsResponse(
+        @SerializedName("project_id") String projectID,
+        @SerializedName("project_name") String projectName,
+        String version,
+        String[] builds
+) {
+}

tools/quick-e2e/src/main/java/de/oliver/quicke2e/paper/PaperDownloadService.java

@@ -0,0 +1,63 @@
+package de.oliver.quicke2e.paper;
+
+import com.google.gson.Gson;
+
+import java.net.URI;
+import java.net.http.HttpClient;
+import java.net.http.HttpRequest;
+import java.net.http.HttpResponse;
+import java.nio.file.Path;
+import java.nio.file.Paths;
+
+public class PaperDownloadService {
+
+    private static final Gson GSON = new Gson();
+    private static final String BASE_URL = "https://api.papermc.io/v2";
+    private static final String destination = "servers";
+
+    private final HttpClient client;
+
+    public PaperDownloadService() {
+        this.client = HttpClient.newHttpClient();
+    }
+
+    public void downloadServerFile(
+            String project,
+            String version,
+            String build
+    ) {
+        Path folderPath = Paths.get(String.format("%s/%s_%s_%s/", destination, project, version, build));
+        if (!folderPath.toFile().exists()) {
+            folderPath.toFile().mkdirs();
+        }
+
+        String buildNumber = build.equals("latest") ? getLatestBuildNumber(project, version) : build;
+
+        Path filePath = Paths.get(String.format("%s/%s_%s_%s/%s-%s-%s.jar", destination, project, version, build, project, version, buildNumber));
+
+        HttpRequest req = HttpRequest.newBuilder()
+                .GET()
+                .uri(URI.create(String.format("%s/projects/%s/versions/%s/builds/%s/downloads/%s-%s-%s.jar", BASE_URL, project, version, buildNumber, project, version, buildNumber)))
+                .build();
+
+        client.sendAsync(req, HttpResponse.BodyHandlers.ofFile(filePath))
+                .thenAccept(_ -> System.out.println("Downloaded server file to " + filePath))
+                .join();
+    }
+
+    private String getLatestBuildNumber(
+            String project,
+            String version
+    ) {
+        HttpRequest req = HttpRequest.newBuilder()
+                .GET()
+                .uri(URI.create(String.format("%s/projects/%s/versions/%s", BASE_URL, project, version)))
+                .build();
+
+        HttpResponse<String> resp = client.sendAsync(req, HttpResponse.BodyHandlers.ofString()).join();
+        BuildsResponse builds = GSON.fromJson(resp.body(), BuildsResponse.class);
+
+        return builds.builds()[builds.builds().length - 1];
+    }
+
+}