Handle disconnect events

README.md

@@ -12,13 +12,15 @@ If the API responds with 401, the player is blocked from joining and the body of
 
 Download a build from the [Releases page](https://github.com/Keweenaw-Kube/diorite/releases) and put it in the `mods/` directory.
 
-After running the server with it installed for the first time, a config file will be created at `mods/diorite/config.yaml`. Fill in `endpoint` with the URL you want Diorite to call. There's an additional, optional property:
+After running the server with it installed for the first time, a config file will be created at `mods/diorite/config.yaml`. Fill in `endpoint` with the URL you want Diorite to call. There's a few additional, optional properties:
 
 ```yml
 # Will make request https://example.com?uuid=player-id&token=my-auth-token
 endpoint: "https://example.com"
 queryParams:
   token: "my-auth-token"
+# If true, will make call on player disconnect like https://example.com?uuid=player-id&state=disconnected
+callOnDisconnect: false
 ```
 
 ### License

src/main/java/net/fabricmc/diorite/DioriteConfig.java

@@ -12,6 +12,7 @@
 public class DioriteConfig {
 	public String endpoint;
 	public HashMap<String, String> queryParams;
+	public boolean callOnDisconnect = false;
 
   private static String getConfigFileLocation() {
 		File root = new File(DioriteMod.class.getProtectionDomain().getCodeSource().getLocation().getPath());

src/main/java/net/fabricmc/diorite/DioriteMod.java

@@ -4,12 +4,20 @@
 import java.io.IOException;
 import java.io.InputStreamReader;
 import java.net.HttpURLConnection;
+import java.net.MalformedURLException;
 import java.net.URL;
 import java.util.HashMap;
+import java.util.UUID;
+import java.util.concurrent.CompletableFuture;
+import java.util.concurrent.Executor;
+import java.util.concurrent.ScheduledThreadPoolExecutor;
 import java.util.stream.Collectors;
 
+import com.google.common.util.concurrent.ThreadFactoryBuilder;
 import com.mojang.authlib.GameProfile;
 
+import net.fabricmc.fabric.api.networking.v1.ServerPlayConnectionEvents;
+import net.minecraft.entity.player.PlayerEntity;
 import net.minecraft.server.MinecraftServer;
 import net.minecraft.server.network.ServerLoginNetworkHandler;
 
@@ -19,14 +27,21 @@
 import net.fabricmc.fabric.api.networking.v1.PacketSender;
 import net.fabricmc.fabric.api.networking.v1.ServerLoginNetworking;
 
+import net.minecraft.server.network.ServerPlayNetworkHandler;
 import net.minecraft.text.LiteralText;
 
 public final class DioriteMod implements ModInitializer {
 	private DioriteConfig config;
+	private Executor scheduler = new ScheduledThreadPoolExecutor(1, new ThreadFactoryBuilder()
+			.setDaemon(true)
+			.setNameFormat("diorite-scheduler")
+			.build());
 
 	@Override
 	public void onInitialize() {
-		ServerLoginConnectionEvents.QUERY_START.register(this::onLoginStart);
+		ServerLoginConnectionEvents.QUERY_START.register(this::onPreLogin);
+
+		ServerPlayConnectionEvents.DISCONNECT.register(this::onDisconnect);
 
 		try {
 			this.config = DioriteConfig.loadConfig();
@@ -41,20 +56,19 @@ public void onInitialize() {
 		}
 	}
 
-	private void onLoginStart(ServerLoginNetworkHandler networkHandler, MinecraftServer server, PacketSender sender, ServerLoginNetworking.LoginSynchronizer synchronizer) {
+	private void onPreLogin(ServerLoginNetworkHandler networkHandler, MinecraftServer server, PacketSender sender, ServerLoginNetworking.LoginSynchronizer sync) {
 		GameProfile profile = ((ServerLoginNetworkHandlerAccessor) networkHandler).getProfile();
+		String playerUUID = PlayerEntity.getUuidFromProfile(profile).toString();
 
-		String playerUUID = profile.getId().toString();
+		sync.waitFor(CompletableFuture.runAsync(() -> onPreLoginAsync(networkHandler, playerUUID), this.scheduler));
+	}
 
+	private void onPreLoginAsync(ServerLoginNetworkHandler networkHandler, String playerUUID) {
 		// Decide here whether to allow connection or not by calling external HTTP API
 		try {
-			HashMap<String, String> queryParams = this.config.queryParams == null ? new HashMap<>() : new HashMap<String, String>(this.config.queryParams);
-
-			queryParams.put("uuid", playerUUID.replaceAll("-", ""));
+			HashMap queryParams = this.getQueryParams(playerUUID);
 
-			URL url = new URL(this.config.endpoint + '?' + DioriteUtil.getQueryParamsFrom(queryParams));
-
-			HttpURLConnection http = (HttpURLConnection) url.openConnection();
+			HttpURLConnection http = (HttpURLConnection) this.getURL(queryParams).openConnection();
 			http.setConnectTimeout(1000);
 			int statusCode = http.getResponseCode();
 
@@ -68,4 +82,41 @@ private void onLoginStart(ServerLoginNetworkHandler networkHandler, MinecraftSer
 			networkHandler.disconnect(new LiteralText("Whitelist API errored out."));
 		}
 	}
+
+	private void onDisconnect(ServerPlayNetworkHandler networkHandler, MinecraftServer server) {
+		String playerUUID = networkHandler.player.getUuidAsString();
+
+		if (this.config.callOnDisconnect) {
+			try {
+				HashMap queryParams = this.getQueryParams(playerUUID);
+
+				queryParams.put("state", "disconnected");
+
+				HttpURLConnection http = (HttpURLConnection) this.getURL(queryParams).openConnection();
+				http.setConnectTimeout(1000);
+				int statusCode = http.getResponseCode();
+
+				if (statusCode == 401) {
+					BufferedReader br = new BufferedReader(new InputStreamReader(http.getErrorStream()));
+					String msg = br.lines().collect(Collectors.joining());
+
+					networkHandler.disconnect(new LiteralText(msg));
+				}
+			} catch (IOException error) {
+				System.err.println("Whitelist API errored out.");
+			}
+		}
+	}
+
+	private HashMap<String, String> getQueryParams(String playerUUID) {
+		HashMap queryParams = this.config.queryParams == null ? new HashMap<>() : new HashMap<String, String>(this.config.queryParams);
+
+		queryParams.put("uuid", playerUUID.replaceAll("-", ""));
+
+		return queryParams;
+	}
+
+	private URL getURL(HashMap<String, String> queryParams) throws MalformedURLException {
+		return new URL(this.config.endpoint + '?' + DioriteUtil.getQueryParamsFrom(queryParams));
+	}
 }