Schematic Caching

Currently schematics are always reuploaded even if they already exist on the server, these changes make it so if they already exist on the server, a schematic pointing towards that is made instead of requiring a full reupload.

src/main/java/com/simibubi/create/Create.java

@@ -2,6 +2,8 @@
 
 import java.util.Random;
 
+import net.minecraftforge.fml.loading.FMLLoader;
+
 import org.slf4j.Logger;
 
 import com.google.gson.Gson;
@@ -152,6 +154,9 @@ public static void onCtor() {
 
 		// FIXME: this is not thread-safe
 		Mods.CURIOS.executeIfInstalled(() -> () -> Curios.init(modEventBus, forgeEventBus));
+
+		if (FMLLoader.getDist().isDedicatedServer())
+			SCHEMATIC_RECEIVER.computeHashes();
 	}
 
 	public static void init(final FMLCommonSetupEvent event) {

src/main/java/com/simibubi/create/content/schematics/SchematicFile.java

@@ -0,0 +1,3 @@
+package com.simibubi.create.content.schematics;
+
+public record SchematicFile(String playerName, String schematicName) {}

src/main/java/com/simibubi/create/content/schematics/SchematicItem.java

@@ -57,6 +57,10 @@ public SchematicItem(Properties properties) {
 		super(properties);
 	}
 
+	public static ItemStack create(HolderGetter<Block> lookup, SchematicFile schematicFile) {
+		return create(lookup, schematicFile.schematicName(), schematicFile.playerName());
+	}
+
 	public static ItemStack create(HolderGetter<Block> lookup, String schematic, String owner) {
 		ItemStack blueprint = AllItems.SCHEMATIC.asStack();
 

src/main/java/com/simibubi/create/content/schematics/ServerSchematicLoader.java

@@ -1,10 +1,13 @@
 package com.simibubi.create.content.schematics;
 
+import java.io.FileInputStream;
 import java.io.IOException;
+import java.io.InputStream;
 import java.io.OutputStream;
 import java.nio.file.Files;
 import java.nio.file.Path;
 import java.nio.file.Paths;
+import java.nio.file.StandardOpenOption;
 import java.util.Comparator;
 import java.util.HashMap;
 import java.util.HashSet;
@@ -24,21 +27,27 @@
 import com.simibubi.create.infrastructure.config.AllConfigs;
 import com.simibubi.create.infrastructure.config.CSchematics;
 
+import it.unimi.dsi.fastutil.objects.Object2ReferenceOpenHashMap;
 import it.unimi.dsi.fastutil.objects.ObjectArrayList;
 import net.minecraft.ChatFormatting;
+import net.minecraft.Util;
 import net.minecraft.core.BlockPos;
 import net.minecraft.core.registries.Registries;
 import net.minecraft.server.level.ServerPlayer;
 import net.minecraft.world.InteractionHand;
 import net.minecraft.world.level.Level;
-import net.minecraft.world.level.block.entity.BlockEntity;
 import net.minecraft.world.level.block.state.BlockState;
 
+import org.apache.commons.codec.digest.DigestUtils;
+import org.jetbrains.annotations.Nullable;
+
 public class ServerSchematicLoader {
 
-	private Map<String, SchematicUploadEntry> activeUploads;
+	private Map<String, SchematicUploadEntry> activeUploads = new HashMap<>();
+
+	private Map<String, SchematicFile> sumToSchematic = new Object2ReferenceOpenHashMap<>();
 
-	public class SchematicUploadEntry {
+	public static class SchematicUploadEntry {
 		public Level world;
 		public BlockPos tablePos;
 		public OutputStream stream;
@@ -56,19 +65,42 @@ public SchematicUploadEntry(OutputStream stream, long totalBytes, Level world, B
 		}
 	}
 
-	public ServerSchematicLoader() {
-		activeUploads = new HashMap<>();
-	}
-
 	public String getSchematicPath() {
 		return "schematics/uploaded";
 	}
 
 	private final ObjectArrayList<String> deadEntries = ObjectArrayList.of();
 
+	@Nullable
+	public SchematicFile getSchematicFileFromSum(String sum) {
+		return sumToSchematic.get(sum);
+	}
+
+	public void computeHashes() {
+		Util.ioPool().submit(() -> {
+			try (Stream<Path> filePaths = Files.find(Path.of(getSchematicPath()), 2,
+					(filePath, attributes) -> filePath.toString().endsWith(".nbt"))) {
+				for (Path path : filePaths.toList()) {
+					try (InputStream stream = new FileInputStream(path.toFile())) {
+						String[] pathSplit = path.toString()
+								.replace("schematics/uploaded/", "")
+								.replace(".nbt", "")
+								.split("/");
+						String playerName = pathSplit[0];
+						String schematicName = pathSplit[1];
+						String schematicMd5Hex = DigestUtils.md5Hex(stream);
+
+						sumToSchematic.computeIfAbsent(schematicMd5Hex, k -> new SchematicFile(playerName, schematicName));
+					}
+				}
+			} catch (IOException ignored) {}
+		});
+	}
+
 	public void tick() {
 		// Detect Timed out Uploads
 		int timeout = getConfig().schematicIdleTimeout.get();
+
 		for (String upload : activeUploads.keySet()) {
 			SchematicUploadEntry entry = activeUploads.get(upload);
 
@@ -82,6 +114,7 @@ public void tick() {
 		for (String toRemove : deadEntries) {
 			this.cancelUpload(toRemove);
 		}
+
 		deadEntries.clear();
 	}
 
@@ -240,17 +273,22 @@ protected void cancelUpload(String playerSchematicId) {
 			table.finishUpload();
 	}
 
+	// Use when the schematic already exists on the server
+	public void useLocalFile(Level level, BlockPos pos, SchematicFile schematicFile) {
+		SchematicTableBlockEntity table = getTable(level, pos);
+		if (table != null) {
+			table.finishUpload();
+			table.inventory.setStackInSlot(1, SchematicItem.create(level.holderLookup(Registries.BLOCK), schematicFile));
+		}
+	}
+
 	public SchematicTableBlockEntity getTable(Level world, BlockPos pos) {
-		BlockEntity be = world.getBlockEntity(pos);
-		if (!(be instanceof SchematicTableBlockEntity))
-			return null;
-		SchematicTableBlockEntity table = (SchematicTableBlockEntity) be;
-		return table;
+		return world.getBlockEntity(pos) instanceof SchematicTableBlockEntity table ? table : null;
 	}
 
 	public void handleFinishedUpload(ServerPlayer player, String schematic) {
-		String playerSchematicId = player.getGameProfile()
-			.getName() + "/" + schematic;
+		String playerName = player.getGameProfile().getName();
+		String playerSchematicId = playerName + "/" + schematic;
 
 		if (activeUploads.containsKey(playerSchematicId)) {
 			try {
@@ -259,6 +297,11 @@ public void handleFinishedUpload(ServerPlayer player, String schematic) {
 				Level world = removed.world;
 				BlockPos pos = removed.tablePos;
 
+				// It'll be fine:tm:
+				try (InputStream stream = Files.newInputStream(Path.of(playerSchematicId), StandardOpenOption.READ)) {
+					sumToSchematic.computeIfAbsent(DigestUtils.md5Hex(stream), k -> new SchematicFile(playerName, schematic));
+				} catch (IOException ignored) {}
+
 				Create.LOGGER.info("New Schematic Uploaded: " + playerSchematicId);
 				if (pos == null)
 					return;
@@ -271,9 +314,7 @@ public void handleFinishedUpload(ServerPlayer player, String schematic) {
 				if (table == null)
 					return;
 				table.finishUpload();
-				table.inventory.setStackInSlot(1, SchematicItem.create(world.holderLookup(Registries.BLOCK), schematic, player.getGameProfile()
-					.getName()));
-
+				table.inventory.setStackInSlot(1, SchematicItem.create(world.holderLookup(Registries.BLOCK), schematic, playerName));
 			} catch (IOException e) {
 				Create.LOGGER.error("Exception Thrown when finishing Upload: " + playerSchematicId);
 				e.printStackTrace();

src/main/java/com/simibubi/create/content/schematics/client/ClientSchematicLoader.java

@@ -28,6 +28,8 @@
 import net.minecraftforge.api.distmarker.Dist;
 import net.minecraftforge.api.distmarker.OnlyIn;
 
+import org.apache.commons.codec.digest.DigestUtils;
+
 @OnlyIn(Dist.CLIENT)
 public class ClientSchematicLoader {
 
@@ -73,7 +75,11 @@ public void startNewUpload(String schematic) {
 
 			in = Files.newInputStream(path, StandardOpenOption.READ);
 			activeUploads.put(schematic, in);
-			AllPackets.getChannel().sendToServer(SchematicUploadPacket.begin(schematic, size));
+
+			try (InputStream stream = Files.newInputStream(path, StandardOpenOption.READ)) {
+				String md5 = DigestUtils.md5Hex(stream);
+				AllPackets.getChannel().sendToServer(SchematicUploadPacket.begin(schematic, size, md5));
+			}
 		} catch (IOException e) {
 			e.printStackTrace();
 		}

src/main/java/com/simibubi/create/content/schematics/packet/SchematicUploadPacket.java

@@ -1,6 +1,7 @@
 package com.simibubi.create.content.schematics.packet;
 
 import com.simibubi.create.Create;
+import com.simibubi.create.content.schematics.SchematicFile;
 import com.simibubi.create.content.schematics.table.SchematicTableMenu;
 import com.simibubi.create.foundation.networking.SimplePacketBase;
 
@@ -9,6 +10,8 @@
 import net.minecraft.server.level.ServerPlayer;
 import net.minecraftforge.network.NetworkEvent.Context;
 
+import java.io.File;
+
 public class SchematicUploadPacket extends SimplePacketBase {
 
 	public static final int BEGIN = 0;
@@ -20,14 +23,17 @@ public class SchematicUploadPacket extends SimplePacketBase {
 	private String schematic;
 	private byte[] data;
 
+	private String md5Hex;
+
 	public SchematicUploadPacket(int code, String schematic) {
 		this.code = code;
 		this.schematic = schematic;
 	}
 
-	public static SchematicUploadPacket begin(String schematic, long size) {
+	public static SchematicUploadPacket begin(String schematic, long size, String md5Hex) {
 		SchematicUploadPacket pkt = new SchematicUploadPacket(BEGIN, schematic);
 		pkt.size = size;
+		pkt.md5Hex = md5Hex;
 		return pkt;
 	}
 
@@ -45,8 +51,10 @@ public SchematicUploadPacket(FriendlyByteBuf buffer) {
 		code = buffer.readInt();
 		schematic = buffer.readUtf(256);
 
-		if (code == BEGIN)
+		if (code == BEGIN) {
 			size = buffer.readLong();
+			md5Hex = buffer.readUtf(32);
+		}
 		if (code == WRITE)
 			data = buffer.readByteArray();
 	}
@@ -56,8 +64,10 @@ public void write(FriendlyByteBuf buffer) {
 		buffer.writeInt(code);
 		buffer.writeUtf(schematic);
 
-		if (code == BEGIN)
+		if (code == BEGIN) {
 			buffer.writeLong(size);
+			buffer.writeUtf(md5Hex);
+		}
 		if (code == WRITE)
 			buffer.writeByteArray(data);
 	}
@@ -69,9 +79,29 @@ public boolean handle(Context context) {
 			if (player == null)
 				return;
 			if (code == BEGIN) {
-				BlockPos pos = ((SchematicTableMenu) player.containerMenu).contentHolder
-						.getBlockPos();
-				Create.SCHEMATIC_RECEIVER.handleNewUpload(player, schematic, size, pos);
+				boolean usedLocalFile = false;
+
+				BlockPos pos = ((SchematicTableMenu) player.containerMenu).contentHolder.getBlockPos();
+
+				SchematicFile schematicFile = Create.SCHEMATIC_RECEIVER.getSchematicFileFromSum(md5Hex);
+
+				if (schematicFile != null) {
+					String filePath = String.format(
+							"%s/%s/%s",
+							Create.SCHEMATIC_RECEIVER.getSchematicPath(),
+							schematicFile.playerName(),
+							schematicFile.schematicName()
+					);
+
+					// Check if the file exists
+					if (new File(filePath).isFile()) {
+						Create.SCHEMATIC_RECEIVER.useLocalFile(player.level(), pos, schematicFile);
+						usedLocalFile = true;
+					}
+				}
+
+				if (!usedLocalFile)
+					Create.SCHEMATIC_RECEIVER.handleNewUpload(player, schematic, size, pos);
 			}
 			if (code == WRITE)
 				Create.SCHEMATIC_RECEIVER.handleWriteRequest(player, schematic, data);