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Merged
Sukikui merged 1 commit into from
Mar 11, 2026
Merged

Harden local API server lifecycle #26

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161 changes: 117 additions & 44 deletions src/client/java/fr/sukikui/playercoordsapi/PlayerCoordsAPIClient.java
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Original file line number Diff line number Diff line change
Expand Up @@ -15,38 +15,35 @@

import java.io.IOException;
import java.io.OutputStream;
import java.net.InetAddress;
import java.net.InetSocketAddress;
import java.nio.charset.StandardCharsets;
import java.util.Locale;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;

public class PlayerCoordsAPIClient implements ClientModInitializer {
private static final int PORT = 25565;
private static final long START_RETRY_DELAY_MS = 5_000L;

private HttpServer server;
private ExecutorService serverExecutor;
private boolean serverStarted = false;
private boolean lastConfigEnabled;
private long nextStartAttemptAt = 0L;
private volatile PlayerSnapshot latestSnapshot;
// Hardcoded port value - no longer in config
private static final int PORT = 25565;

@Override
public void onInitializeClient() {
// Start server on init if enabled
if (PlayerCoordsAPI.getConfig().enabled) {
startServer();
lastConfigEnabled = PlayerCoordsAPI.getConfig().enabled;

if (lastConfigEnabled) {
tryStartServer();
}

// Register tick event to constantly check config status
ClientTickEvents.END_CLIENT_TICK.register(client -> {
updateSnapshot(client);
boolean configEnabled = PlayerCoordsAPI.getConfig().enabled;

// If enabled and server not started, start server
if (configEnabled && !serverStarted) {
startServer();
}

// If disabled and server is running, stop server
if (!configEnabled && serverStarted) {
stopServer();
}
handleConfigState(PlayerCoordsAPI.getConfig().enabled);
});

ClientWorldEvents.AFTER_CLIENT_WORLD_CHANGE.register((client, world) -> updateSnapshot(client));
Expand All @@ -59,6 +56,26 @@ public void onInitializeClient() {
PlayerCoordsAPI.LOGGER.info("Registered config monitor");
}

private void handleConfigState(boolean configEnabled) {
if (configEnabled != lastConfigEnabled) {
lastConfigEnabled = configEnabled;

if (configEnabled) {
nextStartAttemptAt = 0L;
tryStartServer();
} else {
nextStartAttemptAt = 0L;
stopServer();
}

return;
}

if (configEnabled && !serverStarted) {
tryStartServer();
}
}

private void updateSnapshot(MinecraftClient client) {
PlayerEntity player = client.player;
ClientWorld worldObj = client.world;
Expand All @@ -81,7 +98,7 @@ private void updateSnapshot(MinecraftClient client) {
player.getPitch(),
worldObj.getRegistryKey().getValue().toString(),
biome,
player.getUuid().toString(),
player.getUuidAsString(),
player.getName().getString()
);
}
Expand All @@ -90,39 +107,60 @@ private void clearSnapshot() {
latestSnapshot = null;
}

private void startServer() {
if (serverStarted) return;
private void tryStartServer() {
if (serverStarted) {
return;
}

long now = System.currentTimeMillis();

if (now < nextStartAttemptAt) {
return;
}

try {
PlayerCoordsAPI.LOGGER.info("Starting PlayerCoordsAPI HTTP server on port " + PORT);
server = HttpServer.create(new InetSocketAddress(PORT), 0);
server = HttpServer.create(new InetSocketAddress(InetAddress.getLoopbackAddress(), PORT), 0);
server.createContext("/api/coords", this::handleCoordsRequest);
server.setExecutor(Executors.newSingleThreadExecutor());
serverExecutor = Executors.newSingleThreadExecutor();
server.setExecutor(serverExecutor);
server.start();
serverStarted = true;
nextStartAttemptAt = 0L;
PlayerCoordsAPI.LOGGER.info("PlayerCoordsAPI HTTP server started successfully");
} catch (IOException e) {
PlayerCoordsAPI.LOGGER.error("Failed to start PlayerCoordsAPI HTTP server", e);
cleanupServerResources();
nextStartAttemptAt = now + START_RETRY_DELAY_MS;
PlayerCoordsAPI.LOGGER.warn(
"Failed to start PlayerCoordsAPI HTTP server, retrying in {} seconds",
START_RETRY_DELAY_MS / 1000,
e
);
}
}

private void stopServer() {
if (server == null && serverExecutor == null) {
return;
}

PlayerCoordsAPI.LOGGER.info("Stopping PlayerCoordsAPI HTTP server");
cleanupServerResources();
PlayerCoordsAPI.LOGGER.info("PlayerCoordsAPI HTTP server stopped successfully");
}

private void cleanupServerResources() {
if (server != null) {
PlayerCoordsAPI.LOGGER.info("Stopping PlayerCoordsAPI HTTP server");

// Create a separate thread to stop the server to prevent blocking
final HttpServer serverToStop = server; // Create a final reference for the thread
Thread stopThread = new Thread(() -> {
serverToStop.stop(0); // Stop with no delay
PlayerCoordsAPI.LOGGER.info("PlayerCoordsAPI HTTP server stopped successfully");
});
stopThread.setDaemon(true);
stopThread.start();

// Set variables immediately so we know the server is being stopped
server.stop(0);
server = null;
serverStarted = false;
}

if (serverExecutor != null) {
serverExecutor.shutdown();
serverExecutor = null;
}

serverStarted = false;
}

private void handleCoordsRequest(HttpExchange exchange) throws IOException {
Expand All @@ -133,8 +171,8 @@ private void handleCoordsRequest(HttpExchange exchange) throws IOException {
}

// Check if the client is allowed to access (only localhost)
String remoteAddress = exchange.getRemoteAddress().getAddress().getHostAddress();
if (!remoteAddress.equals("127.0.0.1") && !remoteAddress.equals("0:0:0:0:0:0:0:1")) {
InetAddress remoteAddress = exchange.getRemoteAddress().getAddress();
if (remoteAddress == null || !remoteAddress.isLoopbackAddress()) {
sendResponse(exchange, 403, "{\"error\": \"Access denied\"}");
return;
}
Expand All @@ -153,16 +191,43 @@ private void sendResponse(HttpExchange exchange, int statusCode, String response
exchange.getResponseHeaders().set("Access-Control-Allow-Methods", "GET, OPTIONS");
exchange.getResponseHeaders().set("Access-Control-Allow-Headers", "Content-Type, Authorization");

// Set content type if response is not null
if (response != null) {
exchange.getResponseHeaders().set("Content-Type", "application/json");
exchange.sendResponseHeaders(statusCode, response.length());
byte[] responseBytes = response.getBytes(StandardCharsets.UTF_8);
exchange.getResponseHeaders().set("Content-Type", "application/json; charset=utf-8");
exchange.sendResponseHeaders(statusCode, responseBytes.length);
try (OutputStream os = exchange.getResponseBody()) {
os.write(response.getBytes());
os.write(responseBytes);
}
} else {
exchange.sendResponseHeaders(statusCode, -1); // No response body
exchange.sendResponseHeaders(statusCode, -1);
}
}

private static String escapeJson(String value) {
StringBuilder escaped = new StringBuilder(value.length() + 16);

for (int i = 0; i < value.length(); i++) {
char ch = value.charAt(i);

switch (ch) {
case '\\' -> escaped.append("\\\\");
case '"' -> escaped.append("\\\"");
case '\b' -> escaped.append("\\b");
case '\f' -> escaped.append("\\f");
case '\n' -> escaped.append("\\n");
case '\r' -> escaped.append("\\r");
case '\t' -> escaped.append("\\t");
default -> {
if (ch < 0x20) {
escaped.append(String.format(Locale.ROOT, "\\u%04x", (int) ch));
} else {
escaped.append(ch);
}
}
}
}

return escaped.toString();
}

private record PlayerSnapshot(
Expand All @@ -179,7 +244,15 @@ private record PlayerSnapshot(
private String toJson() {
return String.format(Locale.US,
"{\"x\": %.2f, \"y\": %.2f, \"z\": %.2f, \"yaw\": %.2f, \"pitch\": %.2f, \"world\": \"%s\", \"biome\": \"%s\", \"uuid\": \"%s\", \"username\": \"%s\"}",
x, y, z, yaw, pitch, world, biome, uuid, username
x,
y,
z,
yaw,
pitch,
escapeJson(world),
escapeJson(biome),
escapeJson(uuid),
escapeJson(username)
);
}
}
Expand Down
4 changes: 2 additions & 2 deletions src/main/java/fr/sukikui/playercoordsapi/PlayerCoordsAPI.java
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Original file line number Diff line number Diff line change
Expand Up @@ -28,10 +28,10 @@ public void onInitialize() {
// However, some things (like resources) may still be uninitialized.
// Proceed with mild caution.

LOGGER.info("PlayerCoordsAPI initialized - API will be available at http://localhost:25565/api when enabled");
LOGGER.info("PlayerCoordsAPI initialized - API will be available at http://localhost:25565/api/coords when enabled");
}

public static ModConfig getConfig() {
return config;
}
}
}
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