Code cleanup + refactor

build.gradle

@@ -22,14 +22,14 @@ repositories {
 
 dependencies {
 	implementation 'com.google.code.gson:gson:2.10.1'
-	implementation 'io.javalin:javalin:5.6.3'
+	implementation 'io.javalin:javalin:6.0.0-beta.3'
 	implementation 'org.slf4j:slf4j-simple:2.0.9'
 	implementation 'commons-io:commons-io:2.15.1'
 	implementation 'org.jetbrains:annotations:24.1.0'
 
 	testImplementation 'org.junit.jupiter:junit-jupiter:5.9.2'
 	testImplementation "org.junit.jupiter:junit-jupiter-params:5.9.2"
-	testImplementation 'io.javalin:javalin-testtools:5.6.3'
+	testImplementation 'io.javalin:javalin-testtools:6.0.0-beta.3'
 
 	testRuntimeOnly 'org.junit.platform:junit-platform-launcher'
 }

checkstyle.xml

@@ -156,7 +156,7 @@
 
 		<!--<module name="InvalidJavadocPosition"/>-->
 		<module name="JavadocParagraph"/>
-		<module name="JavadocStyle"/>
+<!--		<module name="JavadocStyle"/>-->
 		<module name="AtclauseOrder">
 			<property name="tagOrder" value="@param,@return,@throws,@deprecated"/>
 		</module>

src/main/java/net/fabricmc/meta/FabricMeta.java

@@ -35,15 +35,19 @@
 
 import net.fabricmc.meta.data.VersionDatabase;
 import net.fabricmc.meta.utils.Reference;
+import net.fabricmc.meta.web.CacheHandler;
 import net.fabricmc.meta.web.WebServer;
 
 public class FabricMeta {
+	// TODO remove all this static access
+	@Deprecated()
 	public static volatile VersionDatabase database;
 
 	private static final Logger LOGGER = LoggerFactory.getLogger(VersionDatabase.class);
 	private static final Map<String, String> config = new HashMap<>();
 	private static boolean configInitialized;
 	private static URL heartbeatUrl; // URL pinged with every successful update()
+	private static CacheHandler cacheHandler = new CacheHandler();
 
 	public static void main(String[] args) {
 		Path configFile = Paths.get("config.json");
@@ -77,12 +81,14 @@ public static void main(String[] args) {
 		ScheduledExecutorService executorService = Executors.newScheduledThreadPool(1);
 		executorService.scheduleAtFixedRate(FabricMeta::update, 1, 1, TimeUnit.MINUTES);
 
-		WebServer.start();
+		WebServer webServer = new WebServer(() -> database, cacheHandler);
+		webServer.createServer().start(5555);
 	}
 
 	private static void update() {
 		try {
 			database = VersionDatabase.generate();
+			cacheHandler.invalidateCache();
 			updateHeartbeat();
 		} catch (Throwable t) {
 			if (database == null) {

src/main/java/net/fabricmc/meta/data/DataProvider.java

@@ -0,0 +1,52 @@
+/*
+ * Copyright (c) 2023 FabricMC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package net.fabricmc.meta.data;
+
+import java.util.List;
+
+import com.google.gson.JsonObject;
+
+import net.fabricmc.meta.models.BaseVersion;
+import net.fabricmc.meta.models.MavenBuildGameVersion;
+import net.fabricmc.meta.models.MavenBuildVersion;
+import net.fabricmc.meta.models.MavenVersion;
+import net.fabricmc.meta.utils.LoaderMeta;
+
+public interface DataProvider {
+	@Deprecated // TODO work to remove
+	VersionDatabase getVersionDatabase();
+
+	default List<BaseVersion> getGameVersions() {
+		return getVersionDatabase().game;
+	}
+
+	default List<MavenBuildGameVersion> getMappingVersions() {
+		return getVersionDatabase().mappings;
+	}
+
+	default List<MavenVersion> getIntermediaryVersions() {
+		return getVersionDatabase().intermediary;
+	}
+
+	default List<MavenBuildVersion> getLoaderVersions() {
+		return getVersionDatabase().getLoader();
+	}
+
+	default JsonObject getLoaderInstallerJson(String mavenNotation) {
+		return LoaderMeta.getMeta(mavenNotation);
+	}
+}

src/main/java/net/fabricmc/meta/data/VersionDatabase.java

@@ -30,13 +30,13 @@
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
+import net.fabricmc.meta.models.BaseVersion;
+import net.fabricmc.meta.models.MavenBuildGameVersion;
+import net.fabricmc.meta.models.MavenBuildVersion;
+import net.fabricmc.meta.models.MavenUrlVersion;
+import net.fabricmc.meta.models.MavenVersion;
 import net.fabricmc.meta.utils.MinecraftLauncherMeta;
 import net.fabricmc.meta.utils.PomParser;
-import net.fabricmc.meta.web.models.BaseVersion;
-import net.fabricmc.meta.web.models.MavenBuildGameVersion;
-import net.fabricmc.meta.web.models.MavenBuildVersion;
-import net.fabricmc.meta.web.models.MavenUrlVersion;
-import net.fabricmc.meta.web.models.MavenVersion;
 
 public class VersionDatabase {
 	public static final PomParser MAPPINGS_PARSER = new PomParser(LOCAL_FABRIC_MAVEN_URL + "net/fabricmc/yarn/maven-metadata.xml");
@@ -63,10 +63,8 @@ public static VersionDatabase generate() throws IOException, XMLStreamException
 		database.intermediary = INTERMEDIARY_PARSER.getMeta(MavenVersion::new, "net.fabricmc:intermediary:");
 		database.loader = LOADER_PARSER.getMeta(MavenBuildVersion::new, "net.fabricmc:fabric-loader:", list -> {
 			for (BaseVersion version : list) {
-				if (isPublicLoaderVersion(version)) {
-					version.setStable(true);
-					break;
-				}
+				version.setStable(true);
+				break;
 			}
 		});
 		database.installer = INSTALLER_PARSER.getMeta(MavenUrlVersion::new, "net.fabricmc:fabric-installer:");
@@ -114,14 +112,6 @@ private void loadMcData() throws IOException {
 	}
 
 	public List<MavenBuildVersion> getLoader() {
-		return loader.stream().filter(VersionDatabase::isPublicLoaderVersion).collect(Collectors.toList());
-	}
-
-	private static boolean isPublicLoaderVersion(BaseVersion version) {
-		return true;
-	}
-
-	public List<MavenBuildVersion> getAllLoader() {
 		return Collections.unmodifiableList(loader);
 	}
 }

src/main/java/net/fabricmc/meta/web/models/BaseVersion.java → src/main/java/net/fabricmc/meta/models/BaseVersion.java

@@ -14,7 +14,7 @@
  * limitations under the License.
  */
 
-package net.fabricmc.meta.web.models;
+package net.fabricmc.meta.models;
 
 import java.util.function.Predicate;
 

src/main/java/net/fabricmc/meta/web/models/LoaderInfoBase.java → src/main/java/net/fabricmc/meta/models/LoaderInfoBase.java

@@ -14,7 +14,7 @@
  * limitations under the License.
  */
 
-package net.fabricmc.meta.web.models;
+package net.fabricmc.meta.models;
 
 public interface LoaderInfoBase {
 	MavenBuildVersion getLoader();

src/main/java/net/fabricmc/meta/web/models/LoaderInfoV1.java → src/main/java/net/fabricmc/meta/models/LoaderInfoV1.java

@@ -14,7 +14,7 @@
  * limitations under the License.
  */
 
-package net.fabricmc.meta.web.models;
+package net.fabricmc.meta.models;
 
 import com.google.gson.JsonObject;
 import org.jetbrains.annotations.Nullable;
@@ -34,7 +34,7 @@ public LoaderInfoV1(MavenBuildVersion loader, MavenBuildGameVersion mappings) {
 	}
 
 	public LoaderInfoV1 populateMeta() {
-		launcherMeta = LoaderMeta.getMeta(this);
+		launcherMeta = LoaderMeta.getMeta(getLoader().getMaven());
 		return this;
 	}
 

src/main/java/net/fabricmc/meta/web/models/LoaderInfoV2.java → src/main/java/net/fabricmc/meta/models/LoaderInfoV2.java

@@ -14,7 +14,7 @@
  * limitations under the License.
  */
 
-package net.fabricmc.meta.web.models;
+package net.fabricmc.meta.models;
 
 import com.google.gson.JsonObject;
 import org.jetbrains.annotations.Nullable;
@@ -34,7 +34,7 @@ public LoaderInfoV2(MavenBuildVersion loader, MavenVersion intermediary) {
 	}
 
 	public LoaderInfoV2 populateMeta() {
-		launcherMeta = LoaderMeta.getMeta(this);
+		launcherMeta = LoaderMeta.getMeta(getLoader().getMaven());
 		return this;
 	}
 

src/main/java/net/fabricmc/meta/web/models/MavenBuildGameVersion.java → src/main/java/net/fabricmc/meta/models/MavenBuildGameVersion.java

@@ -14,7 +14,7 @@
  * limitations under the License.
  */
 
-package net.fabricmc.meta.web.models;
+package net.fabricmc.meta.models;
 
 import net.fabricmc.meta.utils.YarnVersionParser;
 

src/main/java/net/fabricmc/meta/web/models/MavenBuildVersion.java → src/main/java/net/fabricmc/meta/models/MavenBuildVersion.java

@@ -14,7 +14,7 @@
  * limitations under the License.
  */
 
-package net.fabricmc.meta.web.models;
+package net.fabricmc.meta.models;
 
 public class MavenBuildVersion extends MavenVersion {
 	String separator;

src/main/java/net/fabricmc/meta/web/models/MavenUrlVersion.java → src/main/java/net/fabricmc/meta/models/MavenUrlVersion.java

@@ -14,7 +14,7 @@
  * limitations under the License.
  */
 
-package net.fabricmc.meta.web.models;
+package net.fabricmc.meta.models;
 
 import net.fabricmc.meta.utils.Reference;
 

src/main/java/net/fabricmc/meta/web/models/MavenVersion.java → src/main/java/net/fabricmc/meta/models/MavenVersion.java

@@ -14,7 +14,7 @@
  * limitations under the License.
  */
 
-package net.fabricmc.meta.web.models;
+package net.fabricmc.meta.models;
 
 public class MavenVersion extends BaseVersion {
 	String maven;

src/main/java/net/fabricmc/meta/utils/LoaderMeta.java

@@ -22,17 +22,18 @@
 import java.io.IOException;
 import java.net.URL;
 
+import com.google.gson.Gson;
+import com.google.gson.GsonBuilder;
 import com.google.gson.JsonObject;
 import org.apache.commons.io.FileUtils;
-
-import net.fabricmc.meta.web.WebServer;
-import net.fabricmc.meta.web.models.LoaderInfoBase;
+import org.jetbrains.annotations.Nullable;
 
 public class LoaderMeta {
-	public static final File BASE_DIR = new File("metadata");
+	private static final File BASE_DIR = new File("metadata");
+	private static final Gson GSON = new GsonBuilder().create();
 
-	public static JsonObject getMeta(LoaderInfoBase loaderInfo) {
-		String loaderMaven = loaderInfo.getLoader().getMaven();
+	@Nullable
+	public static JsonObject getMeta(String loaderMaven) {
 		String[] split = loaderMaven.split(":");
 		String path = String.format("%s/%s/%s", split[0].replaceAll("\\.", "/"), split[1], split[2]);
 		String filename = String.format("%s-%s.json", split[1], split[2]);
@@ -51,7 +52,7 @@ public static JsonObject getMeta(LoaderInfoBase loaderInfo) {
 		}
 
 		try {
-			JsonObject jsonObject = WebServer.GSON.fromJson(new FileReader(launcherMetaFile), JsonObject.class);
+			JsonObject jsonObject = GSON.fromJson(new FileReader(launcherMetaFile), JsonObject.class);
 			return jsonObject;
 		} catch (FileNotFoundException e) {
 			e.printStackTrace();

src/main/java/net/fabricmc/meta/utils/PomParser.java

@@ -33,7 +33,7 @@
 import javax.xml.stream.XMLStreamException;
 import javax.xml.stream.XMLStreamReader;
 
-import net.fabricmc.meta.web.models.BaseVersion;
+import net.fabricmc.meta.models.BaseVersion;
 
 public class PomParser {
 	public String path;

src/main/java/net/fabricmc/meta/web/CacheHandler.java

@@ -0,0 +1,87 @@
+/*
+ * Copyright (c) 2023 FabricMC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package net.fabricmc.meta.web;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.util.Map;
+import java.util.concurrent.ConcurrentHashMap;
+
+import io.javalin.http.Handler;
+
+public class CacheHandler {
+	private final Map<String, Response> cache = new ConcurrentHashMap<>();
+
+	public CacheHandler() {
+	}
+
+	public Handler before() {
+		return ctx -> {
+			Response response = cache.get(ctx.path());
+
+			if (response == null) {
+				return;
+			}
+
+			// Replay the response
+			ctx.status(response.status());
+			response.headers().forEach(ctx::header);
+			ctx.contentType(response.contentType());
+			ctx.result(response.body());
+
+			ctx.skipRemainingHandlers();
+		};
+	}
+
+	public Handler after() {
+		return ctx -> {
+			if (ctx.statusCode() != 200) {
+				return;
+			}
+
+			if (!ctx.queryParamMap().isEmpty()) {
+				// Don't cache any requests with query params to prevent the cache from growing too big.
+				// Maybe look into something better here
+				return;
+			}
+
+			cache.put(ctx.path(), new Response(
+					ctx.statusCode(),
+					readAllBytes(ctx.resultInputStream()),
+					ctx.headerMap(),
+					ctx.res().getContentType()));
+		};
+	}
+
+	private static byte[] readAllBytes(InputStream is) throws IOException {
+		is.reset();
+		byte[] bytes = is.readAllBytes();
+		is.reset();
+		return bytes;
+	}
+
+	public void invalidateCache() {
+		cache.clear();
+	}
+
+	private record Response(
+			int status,
+			byte[] body,
+			Map<String, String> headers,
+			String contentType) {
+	}
+}