Fetch game info

Author: juho05

pom.xml

@@ -5,17 +5,25 @@
   <modelVersion>4.0.0</modelVersion>
 
   <groupId>org.codegame</groupId>
-  <artifactId>client</artifactId>
+  <artifactId>codegame-client</artifactId>
   <version>0.1.0</version>
 
   <name>CodeGame Client</name>
   <url>https://code-game.org</url>
 
   <properties>
-    <maven.compiler.release>11</maven.compiler.release>
+    <maven.compiler.source>17</maven.compiler.source>
+    <maven.compiler.target>17</maven.compiler.target>
+    <maven.compiler.release>17</maven.compiler.release>
+    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
   </properties>
 
   <dependencies>
+    <dependency>
+      <groupId>com.google.code.gson</groupId>
+      <artifactId>gson</artifactId>
+      <version>2.9.1</version>
+    </dependency>
   </dependencies>
 
   <build>

src/main/java/org/codegame/client/Api.java

@@ -0,0 +1,82 @@
+package org.codegame.client;
+
+import java.io.IOException;
+import java.io.InputStreamReader;
+import java.net.HttpURLConnection;
+import java.net.URL;
+import java.util.Arrays;
+
+import javax.net.ssl.HttpsURLConnection;
+
+import com.google.gson.FieldNamingPolicy;
+import com.google.gson.Gson;
+import com.google.gson.GsonBuilder;
+
+public class Api {
+	private String url;
+	private boolean tls;
+	private String baseURL;
+
+	private static Gson json = new GsonBuilder().setFieldNamingPolicy(FieldNamingPolicy.LOWER_CASE_WITH_UNDERSCORES)
+			.create();
+
+	public Api(String url) {
+		this.url = trimURL(url);
+		this.tls = isTLS(this.url);
+		this.baseURL = Api.baseURL("http", this.tls, this.url);
+		HttpURLConnection.setFollowRedirects(true);
+	}
+
+	public GameInfo fetchInfo() throws IOException {
+		URL obj = new URL(this.baseURL + "/api/info");
+		HttpURLConnection con = (HttpURLConnection) obj.openConnection();
+		con.setRequestProperty("Accept", "application/json");
+		InputStreamReader reader = new InputStreamReader(con.getInputStream());
+		int responseCode = con.getResponseCode();
+		if (responseCode != 200)
+			throw new IOException("Failed to fetch game info: unexpected response code: " + responseCode);
+		GameInfo info = json.fromJson(reader, GameInfo.class);
+		return info;
+	}
+
+	static String trimURL(String url) {
+		if (url.endsWith("/"))
+			url = url.substring(0, url.length() - 1);
+		String[] parts = url.split("://");
+		if (parts.length < 2) {
+			return url;
+		}
+		return String.join("://", Arrays.copyOfRange(parts, 1, parts.length));
+	}
+
+	static String baseURL(String protocol, boolean tls, String trimmedURL) {
+		if (tls)
+			return protocol + "s://" + trimmedURL;
+		return protocol + "://" + trimmedURL;
+	}
+
+	static boolean isTLS(String trimmedURL) {
+		try {
+			URL url = new URL(baseURL("http", true, trimmedURL) + "/api/info");
+			HttpsURLConnection connection = (HttpsURLConnection) url.openConnection();
+			connection.getInputStream();
+			if (connection.getSSLSession().isEmpty())
+				return false;
+			return connection.getSSLSession().get().isValid();
+		} catch (IOException e) {
+			return false;
+		}
+	}
+
+	public String getURL() {
+		return url;
+	}
+
+	public String getBaseURL() {
+		return baseURL;
+	}
+
+	public boolean isTLS() {
+		return tls;
+	}
+}

src/main/java/org/codegame/client/GameInfo.java

@@ -0,0 +1,18 @@
+package org.codegame.client;
+
+import com.google.gson.annotations.*;
+
+public class GameInfo {
+	@SerializedName("name")
+	public String name;
+	@SerializedName("cg_version")
+	public String cgVersion;
+	@SerializedName("display_name")
+	public String displayName;
+	@SerializedName("description")
+	public String description;
+	@SerializedName("version")
+	public String version;
+	@SerializedName("repository_url")
+	public String repositoryURL;
+}

src/main/java/org/codegame/client/GameSocket.java

@@ -1,9 +1,13 @@
 package org.codegame.client;
 
-public class GameSocket 
-{
-    public static void main( String[] args )
-    {
-        System.out.println( "Hello World!" );
-    }
+public class GameSocket {
+	private Api api;
+
+	public GameSocket(String url) {
+		api = new Api(url);
+	}
+
+	public Api getApi() {
+		return api;
+	}
 }