Adding support for OAuth2 Client Credentials Flow + dependency upgrades

README.md

@@ -48,7 +48,7 @@ will output something like this:
 
 ## Java API
 
-* Maven project (not yet in a public repository)
+* Maven project (not yet in a public repository). Clone this repo and build locally (see installation instructions below).
 * Uses [```OkHttp```](https://square.github.io/okhttp/) for HTTP requests
 
 ### Installation
@@ -65,12 +65,22 @@ Add the following dependency to your project
 <dependency>
     <groupId>org.opensky</groupId>
     <artifactId>opensky-api</artifactId>
-    <version>1.3.0</version>
+    <version>1.4.0</version>
 </dependency>
 ```
 
 ### Usage
 
+With OAuth clientId / clientSecret:
+```
+OpenSkyApi api = new OpenSkyApi("clientId", "clientSecret", true);
+    OpenSkyStates os = api.getStates(0, null,
+            new OpenSkyApi.BoundingBox(45.8389, 47.8229, 5.9962, 10.5226));
+
+    os.getStates().forEach(System.out::println);
+```
+
+Unauthenticated:
 ```
 OpenSkyStates states = new OpenSkyApi().getStates(0);
 System.out.println("Number of states: " + states.getStates().size());
@@ -85,7 +95,7 @@ In build.gradle, add the following lines
 
     dependencies {
         /* do not delete the other entries, just add this one */
-        compile 'org.opensky:opensky-api:1.3.0'
+        compile 'org.opensky:opensky-api:1.4.0'
     }
 
     repositories {

java/pom.xml

@@ -6,22 +6,23 @@
 
     <groupId>org.opensky</groupId>
     <artifactId>opensky-api</artifactId>
-    <version>1.3.0</version>
+    <version>1.4.0</version>
     <build>
         <plugins>
             <plugin>
                 <groupId>org.apache.maven.plugins</groupId>
                 <artifactId>maven-compiler-plugin</artifactId>
-                <version>3.7.0</version>
+                <version>3.13.0</version>
                 <configuration>
-                    <source>1.7</source>
-                    <target>1.7</target>
+                    <release>17</release>
+                    <source>17</source>
+                    <target>17</target>
                 </configuration>
             </plugin>
             <plugin>
                 <groupId>org.apache.maven.plugins</groupId>
                 <artifactId>maven-source-plugin</artifactId>
-                <version>3.0.1</version>
+                <version>3.3.1</version>
                 <executions>
                     <execution>
                         <id>attach-sources</id>
@@ -34,7 +35,7 @@
             <plugin>
                 <groupId>org.apache.maven.plugins</groupId>
                 <artifactId>maven-javadoc-plugin</artifactId>
-                <version>2.10.4</version>
+                <version>3.10.1</version>
                 <executions>
                     <execution>
                         <id>attach-javadocs</id>
@@ -86,19 +87,18 @@
         <dependency>
             <groupId>com.squareup.okhttp3</groupId>
             <artifactId>okhttp</artifactId>
-            <version>3.6.0</version>
+            <version>4.12.0</version>
         </dependency>
         <dependency>
             <groupId>com.fasterxml.jackson.core</groupId>
             <artifactId>jackson-databind</artifactId>
-            <version>2.12.7.1</version>
+            <version>2.18.2</version>
         </dependency>
 
         <dependency>
-            <groupId>junit</groupId>
-            <artifactId>junit</artifactId>
-            <version>4.13.1</version>
-            <scope>test</scope>
+            <groupId>org.junit.jupiter</groupId>
+            <artifactId>junit-jupiter</artifactId>
+            <version>5.11.4</version>
         </dependency>
 
     </dependencies>

java/src/main/java/org/opensky/api/OpenSkyApi.java

@@ -6,13 +6,15 @@
 import com.fasterxml.jackson.databind.ObjectMapper;
 import com.fasterxml.jackson.databind.module.SimpleModule;
 import okhttp3.*;
+import org.jetbrains.annotations.NotNull;
 import org.opensky.model.OpenSkyStates;
 import org.opensky.model.OpenSkyStatesDeserializer;
 
 import java.io.IOException;
 import java.io.InputStreamReader;
 import java.net.MalformedURLException;
 import java.nio.charset.Charset;
+import java.time.LocalDateTime;
 import java.util.*;
 
 /**
@@ -55,6 +57,45 @@ public Response intercept(Chain chain) throws IOException {
 		}
 	}
 
+	/**
+	 * This class is an implementation of the {@link Interceptor} interface
+	 * used to manage and include the Authorization Bearer Token in HTTP requests.
+	 * <p>
+	 * It intercepts outgoing HTTP requests and adds an "Authorization" header with
+	 * a Bearer token. Tokens are fetched from the provided {@link OpenSkyAuthentication} instance,
+	 * and they are cached with an expiration time for reuse to reduce redundant token requests.
+	 * <p>
+	 * If the token is expired or unavailable, a new token is fetched from the {@link OpenSkyAuthentication}.
+	 */
+	private static class AuthBearerTokenInterceptor implements Interceptor {
+
+		private final OpenSkyAuthentication auth;
+		private String token;
+		private LocalDateTime expirationTime;
+
+		AuthBearerTokenInterceptor(OpenSkyAuthentication auth) {
+			this.auth = auth;
+			this.token = "";
+			this.expirationTime = null;
+		}
+
+		@Override
+		public Response intercept(@NotNull Chain chain) throws IOException {
+			LocalDateTime now = LocalDateTime.now();
+
+			if (token.isEmpty() || expirationTime == null || now.isAfter(expirationTime)) {
+				token = auth.accessToken();
+				expirationTime = LocalDateTime.now().plusMinutes(30);
+			}
+
+			Request req = chain.request()
+					.newBuilder()
+					.header("Authorization", "Bearer " + token)
+					.build();
+			return chain.proceed(req);
+		}
+	}
+
 	/**
 	 * Create an instance of the API for anonymous access.
 	 */
@@ -66,6 +107,8 @@ public OpenSkyApi() {
 	 * Create an instance of the API for authenticated access
 	 * @param username an OpenSky username
 	 * @param password an OpenSky password for the given username
+	 * @deprecated Use OAuth2 clientId/clientSecret authentication flow
+	 * @see #OpenSkyApi(OpenSkyAuthentication)
 	 */
 	public OpenSkyApi(String username, String password) {
 		lastRequestTime = new HashMap<>();
@@ -86,6 +129,25 @@ public OpenSkyApi(String username, String password) {
         }
 	}
 
+	public OpenSkyApi(OpenSkyAuthentication auth) {
+		lastRequestTime = new HashMap<>();
+		// set up JSON mapper
+		mapper = new ObjectMapper();
+		SimpleModule sm = new SimpleModule();
+		sm.addDeserializer(OpenSkyStates.class, new OpenSkyStatesDeserializer());
+		mapper.registerModule(sm);
+
+		authenticated = auth != null;
+
+		if (authenticated) {
+			okHttpClient = new OkHttpClient.Builder()
+					.addInterceptor(new AuthBearerTokenInterceptor(auth))
+					.build();
+		} else {
+			okHttpClient = new OkHttpClient();
+		}
+	}
+
 	/** Make the actual HTTP Request and return the parsed response
 	 * @param baseUri base uri to request
 	 * @param nvps name value pairs to be sent as query parameters

java/src/main/java/org/opensky/api/OpenSkyAuthentication.java

@@ -0,0 +1,63 @@
+package org.opensky.api;
+
+import okhttp3.*;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import com.fasterxml.jackson.databind.JsonNode;
+
+import java.io.IOException;
+
+/**
+ * The Authentication class is responsible for handling authentication
+ * requests to retrieve an access token from the OpenSky Network's authentication API.
+ */
+public class OpenSkyAuthentication {
+    private final String clientId;
+    private final String clientSecret;
+
+    public OpenSkyAuthentication(String clientId, String clientSecret) {
+        this.clientId = clientId;
+        this.clientSecret = clientSecret;
+    }
+
+    /**
+     * The API endpoint for retrieving an access token from the OpenSky Network's authentication system.
+     * This URL is used to send authentication requests with client credentials to obtain access tokens.
+     */
+    private static final String TOKEN_API =
+            "https://auth.opensky-network.org/auth/realms/opensky-network/protocol/openid-connect/token";
+
+
+    public String accessToken() {
+        // Create the OkHttpClient instance
+        OkHttpClient client = new OkHttpClient();
+
+        // Build the request body with the required parameters
+        RequestBody requestBody = new FormBody.Builder()
+                .add("grant_type", "client_credentials")
+                .add("client_id", clientId)
+                .add("client_secret", clientSecret)
+                .build();
+
+        // Create the POST request
+        Request request = new Request.Builder()
+                .url(TOKEN_API)
+                .post(requestBody)
+                .addHeader("Content-Type", "application/x-www-form-urlencoded")
+                .build();
+
+        // Execute the request
+        try (Response response = client.newCall(request).execute()) {
+            if (response.isSuccessful() && response.body() != null) {
+                String responseBody = response.body().string();
+                ObjectMapper mapper = new ObjectMapper();
+                JsonNode jsonNode = mapper.readTree(responseBody);
+                return jsonNode.get("access_token").asText();
+            } else {
+                throw new RuntimeException("Failed to fetch access token. Response: " + response);
+            }
+        } catch (IOException e) {
+            throw new RuntimeException(e);
+        }
+
+    }
+}

java/src/main/java/org/opensky/model/OpenSkyStatesDeserializer.java

@@ -4,6 +4,7 @@
 import com.fasterxml.jackson.core.JsonParser;
 import com.fasterxml.jackson.core.JsonToken;
 import com.fasterxml.jackson.databind.DeserializationContext;
+import com.fasterxml.jackson.databind.JsonMappingException;
 import com.fasterxml.jackson.databind.deser.std.StdDeserializer;
 
 import java.io.IOException;
@@ -87,16 +88,19 @@ private Collection<StateVector> deserializeStates(JsonParser jp) throws IOExcept
 	@Override
 	public OpenSkyStates deserialize(JsonParser jp, DeserializationContext dc) throws IOException {
 		if (jp.getCurrentToken() != null && jp.getCurrentToken() != JsonToken.START_OBJECT) {
-			throw dc.mappingException(OpenSkyStates.class);
+			throw JsonMappingException.from(dc,
+					"Cannot map "
+							+ OpenSkyStates.class.getSimpleName()
+							+ ".Expected START_OBJECT but got " + jp.getCurrentToken());
 		}
 		try {
 			OpenSkyStates res = new OpenSkyStates();
 			for (jp.nextToken(); jp.getCurrentToken() != null && jp.getCurrentToken() != JsonToken.END_OBJECT; jp.nextToken()) {
 				if (jp.getCurrentToken() == JsonToken.FIELD_NAME) {
-					if ("time".equalsIgnoreCase(jp.getCurrentName())) {
+					if ("time".equalsIgnoreCase(jp.currentName())) {
 						int t = jp.nextIntValue(0);
 						res.setTime(t);
-					} else if ("states".equalsIgnoreCase(jp.getCurrentName())) {
+					} else if ("states".equalsIgnoreCase(jp.currentName())) {
 						jp.nextToken();
 						res.setStates(deserializeStates(jp));
 					} else {
@@ -107,7 +111,10 @@ public OpenSkyStates deserialize(JsonParser jp, DeserializationContext dc) throw
 			}
 			return res;
 		} catch (JsonParseException jpe) {
-			throw dc.mappingException(OpenSkyStates.class);
+			throw JsonMappingException.from(dc,
+					"Cannot map "
+							+ OpenSkyStates.class.getSimpleName()
+							+ ".Expected START_OBJECT but got " + jp.getCurrentToken());
 		}
 	}
 }

java/src/test/java/TestOpenSkyApi.java

@@ -1,10 +1,10 @@
-import org.junit.Test;
+import org.junit.jupiter.api.Test;
 import org.opensky.api.OpenSkyApi;
 import org.opensky.model.OpenSkyStates;
 import org.opensky.model.StateVector;
 
 import java.io.IOException;
-import static org.junit.Assert.*;
+import static org.junit.jupiter.api.Assertions.*;
 
 /**
  * @author Markus Fuchs, fuchs@opensky-network.org
@@ -24,12 +24,12 @@ public void testAnonGetStates() throws IOException, InterruptedException {
 		OpenSkyStates os = api.getStates(0, null);
 		long t1 = System.nanoTime();
 		System.out.println("Request anonStates time = " + ((t1 - t0) / 1000000) + "ms");
-		assertTrue("More than 1 state vector", os.getStates().size() > 1);
+		assertTrue(os.getStates().size() > 1, "More than 1 state vector");
 		int time = os.getTime();
 
 		// more than two requests withing ten seconds
 		os = api.getStates(0, null);
-		assertNull("No new data", os);
+		assertNull(os, "No new data");
 
 		// wait ten seconds
 		Thread.sleep(10000);
@@ -40,7 +40,7 @@ public void testAnonGetStates() throws IOException, InterruptedException {
 		t1 = System.nanoTime();
 		System.out.println("Request anonStates time = " + ((t1 - t0) / 1000000) + "ms");
 		assertNotNull(os);
-		assertTrue("More than 1 state vector for second valid request", os.getStates().size() > 1);
+		assertTrue(os.getStates().size() > 1, "More than 1 state vector for second valid request");
 		assertNotEquals(time, os.getTime());
 
 		// test bounding box around Switzerland
@@ -75,7 +75,7 @@ public void testAnonGetStates() throws IOException, InterruptedException {
 		}
 
 		OpenSkyStates os2 = api.getStates(0, null, new OpenSkyApi.BoundingBox(45.8389, 47.8229, 5.9962, 10.5226));
-		assertTrue("Much less states in Switzerland area than world-wide", os2.getStates().size() < os.getStates().size() - 200);
+		assertTrue(os2.getStates().size() < os.getStates().size() - 200, "Much less states in Switzerland area than world-wide");
 	}
 
 	// can only be tested with a valid account
@@ -88,12 +88,12 @@ public void testAuthGetStates() throws IOException, InterruptedException {
 
 		OpenSkyApi api = new OpenSkyApi(USERNAME, PASSWORD);
 		OpenSkyStates os = api.getStates(0, null);
-		assertTrue("More than 1 state vector", os.getStates().size() > 1);
+		assertTrue(os.getStates().size() > 1, "More than 1 state vector");
 		int time = os.getTime();
 
 		// more than two requests withing ten seconds
 		os = api.getStates(0, null);
-		assertNull("No new data", os);
+		assertNull(os, "No new data");
 
 		// wait five seconds
 		Thread.sleep(5000);
@@ -104,7 +104,7 @@ public void testAuthGetStates() throws IOException, InterruptedException {
 		long t1 = System.nanoTime();
 		System.out.println("Request authStates time = " + ((t1 - t0) / 1000000) + "ms");
 		assertNotNull(os);
-		assertTrue("More than 1 state vector for second valid request", os.getStates().size() > 1);
+		assertTrue(os.getStates().size() > 1, "More than 1 state vector for second valid request");
 		assertNotEquals(time, os.getTime());
 	}
 
@@ -116,8 +116,8 @@ public void testAnonGetMyStates() {
 			fail("Anonymous access of 'myStates' expected");
 		} catch (IllegalAccessError iae) {
 			// like expected
-			assertTrue("Mismatched exception message",
-					iae.getMessage().equals("Anonymous access of 'myStates' not allowed"));
+			assertTrue(iae.getMessage().equals("Anonymous access of 'myStates' not allowed"),
+					"Mismatched exception message");
 		} catch (IOException e) {
 			fail("Request should not be submitted");
 		}
@@ -141,7 +141,7 @@ public void testAuthGetMyStates() throws IOException {
 
 		OpenSkyApi api = new OpenSkyApi(USERNAME, PASSWORD);
 		OpenSkyStates os = api.getMyStates(0, null, SERIALS);
-		assertTrue("More than 1 state vector", os.getStates().size() > 1);
+		assertTrue(os.getStates().size() > 1, "More than 1 state vector");
 
 		for (StateVector sv : os.getStates()) {
 			// all states contain at least one of the user's sensors