Improve fabric loader processor by better utilizing fabric meta API

Removes a bunch of hardcoded workarounds :)

launcher-builder/src/main/java/com/skcraft/launcher/builder/PackageBuilder.java

@@ -174,6 +174,11 @@ public class PackageBuilder {
         if (processor != null) {
             LoaderResult result = processor.process(file, manifest, mapper, baseDir);
 
+            if (result == null) {
+                log.warning("Loader " + file.getName() + " failed to process.");
+                return;
+            }
+
             loaderLibraries.addAll(result.getLoaderLibraries());
             installerLibraries.addAll(result.getProcessorLibraries());
             jarMavens.addAll(result.getJarMavens());

launcher-builder/src/main/java/com/skcraft/launcher/builder/loaders/FabricLoaderProcessor.java

@@ -1,23 +1,19 @@
 package com.skcraft.launcher.builder.loaders;
 
-import com.fasterxml.jackson.core.type.TypeReference;
 import com.fasterxml.jackson.databind.ObjectMapper;
-import com.google.common.collect.Iterables;
 import com.google.common.io.Closer;
 import com.skcraft.launcher.builder.BuilderUtils;
-import com.skcraft.launcher.model.loader.MavenUrl;
+import com.skcraft.launcher.model.loader.FabricMod;
-import com.skcraft.launcher.model.loader.profiles.FabricInstallProfile;
 import com.skcraft.launcher.model.minecraft.Library;
+import com.skcraft.launcher.model.minecraft.VersionManifest;
 import com.skcraft.launcher.model.modpack.Manifest;
 import com.skcraft.launcher.util.HttpRequest;
 import lombok.extern.java.Log;
-import org.apache.commons.io.FilenameUtils;
 
 import java.io.File;
 import java.io.IOException;
 import java.io.InputStreamReader;
 import java.net.URL;
-import java.util.List;
 import java.util.jar.JarFile;
 import java.util.zip.ZipEntry;
 
@@ -30,76 +26,39 @@ public class FabricLoaderProcessor implements ILoaderProcessor {
 		Closer closer = Closer.create();
 
 		try {
-			ZipEntry installerEntry = BuilderUtils.getZipEntry(jarFile, "fabric-installer.json");
+			String loaderVersion;
 
-			if (installerEntry != null) {
+			ZipEntry modEntry = BuilderUtils.getZipEntry(jarFile, "fabric.mod.json");
-				InputStreamReader reader = new InputStreamReader(jarFile.getInputStream(installerEntry));
+			if (modEntry != null) {
-				FabricInstallProfile profile = mapper.readValue(
+				InputStreamReader reader = new InputStreamReader(jarFile.getInputStream(modEntry));
-						BuilderUtils.readStringFromStream(closer.register(reader)), FabricInstallProfile.class);
+				FabricMod loaderMod = mapper.readValue(
+						BuilderUtils.readStringFromStream(closer.register(reader)), FabricMod.class);
 
-				// Check version
+				loaderVersion = loaderMod.getVersion();
-				if (profile.getVersion() != 1) {
+			} else {
-					log.warning(String.format("Fabric installer metadata version is %d - we expect version 1.",
+				log.warning("Fabric loader has no 'fabric.mod.json' file, is it really a Fabric Loader jar?");
-							profile.getVersion()));
+				return null;
-				}
+			}
 
-				// Add libraries (TODO: Add server-only libraries to somewhere)
+			log.info("Downloading fabric metadata...");
-				Iterable<Library> libraries = Iterables.concat(profile.getLibraries().getClient(),
+			URL metaUrl = HttpRequest.url(
-						profile.getLibraries().getCommon());
+					String.format("https://meta.fabricmc.net/v2/versions/loader/%s/%s/profile/json",
-				for (Library library : libraries) {
+							manifest.getGameVersion(), loaderVersion));
-					result.getLoaderLibraries().add(library);
+			VersionManifest fabricManifest = HttpRequest.get(metaUrl)
-					log.info("Adding loader library " + library.getName());
+					.execute()
-				}
+					.expectResponseCode(200)
+					.returnContent()
+					.asJson(VersionManifest.class);
 
-				// Add actual loader jar into library path
+			for (Library library : fabricManifest.getLibraries()) {
-				if (profile.getLoader() != null) {
+				result.getLoaderLibraries().add(library);
-					result.getLoaderLibraries().add(profile.getLoader());
+				log.info("Adding loader library " + library.getName());
-					log.info(String.format("Adding Fabric Loader '%s'", profile.getLoader().getName()));
+			}
-				} else {
-					log.warning("Fabric loader metadata is missing a `loader` section, making up a fake library");
-					Library loader = new Library();
-					loader.setName("faked:loader:" + FilenameUtils.getBaseName(loaderJar.getName()));
 
-					Library.Downloads downloads = new Library.Downloads();
+			String mainClass = fabricManifest.getMainClass();
-					downloads.setArtifact(new Library.Artifact());
+			if (mainClass != null) {
-					downloads.getArtifact().setPath(loaderJar.getName());
+				manifest.getVersionManifest().setMainClass(mainClass);
-					downloads.getArtifact().setUrl("");
+				log.info("Using main class " + mainClass);
-					loader.setDownloads(downloads);
-
-					result.getLoaderLibraries().add(loader);
-					// Little bit of a hack here, pretending the filesystem is a maven
-					result.getJarMavens().add(new URL("file:" + loaderJar.getParentFile().getAbsolutePath() + "/"));
-				}
-
-				// Set main class
-				String mainClass = profile.getMainClass().getClient();
-				if (mainClass != null) {
-					manifest.getVersionManifest().setMainClass(mainClass);
-					log.info("Using main class " + mainClass);
-				}
-
-				// Add intermediary library
-				log.info("Downloading fabric metadata...");
-				URL url = HttpRequest.url("https://meta.fabricmc.net/v2/versions/intermediary/"
-						+ manifest.getVersionManifest().getId());
-				List<MavenUrl> versions = HttpRequest.get(url)
-						.execute()
-						.expectResponseCode(200)
-						.returnContent()
-						.asJson(new TypeReference<List<MavenUrl>>() {});
-
-				if (versions != null && versions.size() > 0) {
-					MavenUrl intermediaryLib = versions.get(0);
-
-					if (intermediaryLib.getUrl() == null) {
-						// FIXME temporary hack since maven URL is missing, hopefully can go away soon
-						//  waiting on PR FabricMC/fabric-meta#9
-						intermediaryLib.setUrl("https://maven.fabricmc.net/");
-					}
-
-					result.getLoaderLibraries().add(intermediaryLib.toLibrary());
-					log.info("Added intermediary " + intermediaryLib.getName());
-				}
 			}
 		} catch (InterruptedException e) {
 			log.warning("HTTP request to fabric metadata API was interrupted, this will probably not work!");

launcher/src/main/java/com/skcraft/launcher/model/loader/FabricMod.java

@@ -0,0 +1,12 @@
+package com.skcraft.launcher.model.loader;
+
+import com.fasterxml.jackson.annotation.JsonIgnoreProperties;
+import lombok.Data;
+
+@Data
+@JsonIgnoreProperties(ignoreUnknown = true)
+public class FabricMod {
+	private String id;
+	private String name;
+	private String version;
+}

launcher/src/main/java/com/skcraft/launcher/model/loader/profiles/FabricInstallProfile.java

@@ -1,18 +0,0 @@
-package com.skcraft.launcher.model.loader.profiles;
-
-import com.fasterxml.jackson.annotation.JsonIgnoreProperties;
-import com.skcraft.launcher.model.loader.ExtendedSidedData;
-import com.skcraft.launcher.model.loader.SidedData;
-import com.skcraft.launcher.model.minecraft.Library;
-import lombok.Data;
-
-import java.util.List;
-
-@Data
-@JsonIgnoreProperties(ignoreUnknown = true)
-public class FabricInstallProfile {
-	private int version;
-	private Library loader;
-	private ExtendedSidedData<List<Library>> libraries;
-	private SidedData<String> mainClass;
-}