Mojang service

pom.xml

@@ -48,6 +48,12 @@
             <version>1.18.32</version>
             <scope>provided</scope>
         </dependency>
+        <dependency>
+            <groupId>com.google.code.gson</groupId>
+            <artifactId>gson</artifactId>
+            <version>2.10.1</version>
+            <scope>compile</scope>
+        </dependency>
 
         <!-- Tests -->
         <dependency>

src/main/java/me/braydon/mc/RESTfulMC.java

@@ -1,5 +1,7 @@
 package me.braydon.mc;
 
+import com.google.gson.Gson;
+import com.google.gson.GsonBuilder;
 import lombok.NonNull;
 import lombok.SneakyThrows;
 import lombok.extern.slf4j.Slf4j;
@@ -16,9 +18,14 @@ import java.util.Objects;
  */
 @SpringBootApplication
 @Slf4j(topic = "RESTfulMC")
-public final class RESTfulMC {
+public class RESTfulMC {
+    public static final Gson GSON = new GsonBuilder()
+            .serializeNulls()
+            .create();
+
     @SneakyThrows
     public static void main(@NonNull String[] args) {
+        // Handle loading of our configuration file
         File config = new File("application.yml");
         if (!config.exists()) { // Saving the default config if it doesn't exist locally
             Files.copy(Objects.requireNonNull(RESTfulMC.class.getResourceAsStream("/application.yml")), config.toPath(), StandardCopyOption.REPLACE_EXISTING);
@@ -28,6 +35,8 @@ public final class RESTfulMC {
             return;
         }
         log.info("Found configuration at '{}'", config.getAbsolutePath()); // Log the found config
+
+        // Start the app
         SpringApplication.run(RESTfulMC.class, args);
     }
 }

src/main/java/me/braydon/mc/service/MojangAPI.java

@@ -0,0 +1,13 @@
+package me.braydon.mc.service;
+
+/**
+ * Endpoints for the Mojang API.
+ *
+ * @author Braydon
+ */
+public class MojangAPI {
+    private static final String SESSION_SERVER_ENDPOINT = "https://sessionserver.mojang.com";
+    private static final String API_ENDPOINT = "https://api.mojang.com";
+    protected static final String UUID_TO_PROFILE = SESSION_SERVER_ENDPOINT + "/session/minecraft/profile/%s";
+    protected static final String USERNAME_TO_UUID = API_ENDPOINT + "/users/profiles/minecraft/%s";
+}

src/main/java/me/braydon/mc/service/MojangService.java

@@ -0,0 +1,93 @@
+package me.braydon.mc.service;
+
+import lombok.NonNull;
+import lombok.extern.log4j.Log4j2;
+import me.braydon.mc.common.UUIDUtils;
+import me.braydon.mc.common.web.JsonWebException;
+import me.braydon.mc.common.web.JsonWebRequest;
+import me.braydon.mc.exception.impl.BadRequestException;
+import me.braydon.mc.exception.impl.ResourceNotFoundException;
+import me.braydon.mc.model.Player;
+import me.braydon.mc.model.token.MojangProfileToken;
+import me.braydon.mc.model.token.MojangUsernameToUUIDToken;
+import org.springframework.http.HttpMethod;
+import org.springframework.stereotype.Service;
+
+import java.util.UUID;
+
+/**
+ * A service for interacting with the Mojang API.
+ *
+ * @author Braydon
+ */
+@Service
+@Log4j2(topic = "Mojang Service")
+public final class MojangService {
+    /**
+     * Get a player by their username or UUID.
+     *
+     * @param query the query to search for the player by
+     * @return the player
+     * @throws BadRequestException if the UUID is malformed
+     * @throws ResourceNotFoundException if the player is not found
+     */
+    @NonNull
+    public Player getPlayer(@NonNull String query) throws BadRequestException, ResourceNotFoundException {
+        log.info("Requesting player with query: {}", query);
+
+        UUID uuid; // The player UUID to lookup
+        boolean fullLength = query.length() == 36; // Was a UUID provided?
+        if (query.length() == 32 || fullLength) { // Parse the query as a UUID
+            try {
+                uuid = fullLength ? UUID.fromString(query) : UUIDUtils.addDashes(query);
+                log.info("Parsed {}UUID: {} -> {}", fullLength ? "" : "trimmed ", query, uuid);
+            } catch (IllegalArgumentException ex) {
+                throw new BadRequestException("Malformed UUID provided: %s".formatted(query));
+            }
+        } else { // The query is a username, request from Mojang
+            uuid = usernameToUUID(query);
+            log.info("Found UUID for username {}: {}", query, uuid);
+        }
+
+        // Send a request to Mojang requesting
+        // the player profile by their UUID
+        try {
+            log.info("Retrieving player profile for UUID: {}", uuid);
+            MojangProfileToken token = JsonWebRequest.makeRequest(
+                    MojangAPI.UUID_TO_PROFILE.formatted(uuid), HttpMethod.GET
+            ).execute(MojangProfileToken.class);
+
+            // Return our player model representing the requested player
+            return new Player(uuid, token.getName(), token.getProfileActions());
+        } catch (JsonWebException ex) {
+            // No profile found, return null
+            if (ex.getStatusCode() == 400) {
+                throw new ResourceNotFoundException("Player not found with query: %s".formatted(query));
+            }
+            throw ex;
+        }
+    }
+
+    /**
+     * Get the UUID of a player by their username.
+     *
+     * @param username the player's username
+     * @return the player's UUID
+     * @throws ResourceNotFoundException if the player isn't found
+     */
+    @NonNull
+    private UUID usernameToUUID(@NonNull String username) throws ResourceNotFoundException {
+        // Make a request to Mojang requesting the UUID
+        try {
+            MojangUsernameToUUIDToken token = JsonWebRequest.makeRequest(
+                    MojangAPI.USERNAME_TO_UUID.formatted(username), HttpMethod.GET
+            ).execute(MojangUsernameToUUIDToken.class);
+            return UUIDUtils.addDashes(token.getId()); // Return the UUID with dashes
+        } catch (JsonWebException ex) {
+            if (ex.getStatusCode() == 404) {
+                throw new ResourceNotFoundException("Player not found with username: %s".formatted(username));
+            }
+            throw ex;
+        }
+    }
+}