feature: add examples for version 3

examples/pom.xml

@@ -20,21 +20,25 @@
 
     <dependencies>
         <dependency>
-            <groupId>io.github.nbaars</groupId>
+            <groupId>${project.groupId}</groupId>
             <artifactId>paseto4j-commons</artifactId>
             <version>${project.version}</version>
         </dependency>
         <dependency>
-            <groupId>io.github.nbaars</groupId>
+            <groupId>${project.groupId}</groupId>
             <artifactId>paseto4j-version1</artifactId>
             <version>${project.version}</version>
         </dependency>
-        <!-- Start: only for Paseto Version 2 -->
         <dependency>
-            <groupId>io.github.nbaars</groupId>
+            <groupId>${project.groupId}</groupId>
             <artifactId>paseto4j-version2</artifactId>
             <version>${project.version}</version>
         </dependency>
+        <dependency>
+            <groupId>${project.groupId}</groupId>
+            <artifactId>paseto4j-version3</artifactId>
+            <version>${project.version}</version>
+        </dependency>
         <dependency>
             <groupId>org.apache.tuweni</groupId>
             <artifactId>tuweni-bytes</artifactId>
@@ -51,6 +55,9 @@
             <artifactId>tuweni-crypto</artifactId>
             <version>2.3.1</version>
         </dependency>
-        <!-- End: only for Paseto Version 2 -->
+        <dependency>
+            <groupId>org.bouncycastle</groupId>
+            <artifactId>bcprov-jdk15on</artifactId>
+        </dependency>
     </dependencies>
 </project>

examples/src/main/java/org/paseto4j/version2/Version1.java → examples/src/main/java/org/paseto4j/examples/Version1.java

@@ -22,11 +22,15 @@
  * SOFTWARE.
  */
 
-package org.paseto4j.version2;
+package org.paseto4j.examples;
 
 import static org.paseto4j.commons.Version.V1;
 
-import java.security.*;
+import java.security.KeyPair;
+import java.security.KeyPairGenerator;
+import java.security.NoSuchAlgorithmException;
+import java.security.SecureRandom;
+import java.security.SignatureException;
 import org.paseto4j.commons.PrivateKey;
 import org.paseto4j.commons.PublicKey;
 import org.paseto4j.commons.SecretKey;
@@ -85,7 +89,8 @@ private static KeyPair generateKeyPair() {
   }
 
   private static void exampleV1Local() {
-    byte[] secretKey = SecureRandom.getSeed(32);
+    byte[] secretKey = new byte[32];
+    secretKey = SecureRandom.getSeed(32);
     String encryptedToken = Paseto.encrypt(new SecretKey(secretKey, V1), TOKEN, FOOTER);
     System.out.println("Encrypted token is: " + encryptedToken);
 

examples/src/main/java/org/paseto4j/version2/Version2.java → examples/src/main/java/org/paseto4j/examples/Version2.java

@@ -1,11 +1,12 @@
-package org.paseto4j.version2;
+package org.paseto4j.examples;
 
 import java.security.SignatureException;
 import org.apache.tuweni.bytes.Bytes;
 import org.apache.tuweni.crypto.sodium.Signature;
 import org.paseto4j.commons.PrivateKey;
 import org.paseto4j.commons.PublicKey;
 import org.paseto4j.commons.Version;
+import org.paseto4j.version2.Paseto;
 
 public class Version2 {
 

examples/src/main/java/org/paseto4j/examples/Version3.java

@@ -0,0 +1,76 @@
+package org.paseto4j.examples;
+
+import static org.paseto4j.commons.Version.V3;
+
+import java.security.KeyPair;
+import java.security.KeyPairGenerator;
+import java.security.SecureRandom;
+import java.security.SignatureException;
+import java.security.spec.ECGenParameterSpec;
+import org.bouncycastle.jce.provider.BouncyCastleProvider;
+import org.paseto4j.commons.PrivateKey;
+import org.paseto4j.commons.PublicKey;
+import org.paseto4j.commons.SecretKey;
+import org.paseto4j.version3.Paseto;
+
+public class Version3 {
+
+  private static final String TOKEN =
+      "{\"data\":\"this is a signed message\",\"expires\":\"2019-01-01T00:00:00+00:00\"}";
+  private static final String FOOTER = "Paragon Initiative Enterprises";
+
+  public static void main(String... args) throws SignatureException {
+    exampleV3Local();
+    exampleV3Public();
+
+    try {
+      exampleV3PublicSignatureInvalid();
+    } catch (Exception e) {
+      System.out.println("Token is not valid");
+    }
+  }
+
+  private static void exampleV3Public() throws SignatureException {
+    KeyPair keyPair = generateKeyPair();
+
+    String signedToken = Paseto.sign(new PrivateKey(keyPair.getPrivate(), V3), TOKEN, FOOTER);
+    System.out.println("Signed token is: " + signedToken);
+
+    String token = Paseto.parse(new PublicKey(keyPair.getPublic(), V3), signedToken, FOOTER);
+    System.out.println("Signature is valid, token is: " + token);
+  }
+
+  private static void exampleV3PublicSignatureInvalid() throws SignatureException {
+    KeyPair keyPair1 = generateKeyPair();
+    KeyPair keyPair2 = generateKeyPair();
+
+    String signedToken = Paseto.sign(new PrivateKey(keyPair1.getPrivate(), V3), TOKEN, FOOTER);
+    System.out.println("Signed token is: " + signedToken);
+
+    String token = Paseto.parse(new PublicKey(keyPair2.getPublic(), V3), signedToken, FOOTER);
+    System.out.println("Signature is valid, token is: " + token);
+  }
+
+  private static KeyPair generateKeyPair() {
+    try {
+      var generator = KeyPairGenerator.getInstance("EC", BouncyCastleProvider.PROVIDER_NAME);
+      var spec = new ECGenParameterSpec("secp384r1");
+      generator.initialize(spec);
+      return generator.generateKeyPair();
+    } catch (Exception e) {
+      throw new RuntimeException(e);
+    }
+  }
+
+  private static void exampleV3Local() {
+    byte[] secretKey = new byte[32];
+    new SecureRandom().nextBytes(secretKey);
+
+    SecretKey key = new SecretKey(secretKey, V3);
+    String encryptedToken = Paseto.encrypt(key, TOKEN, FOOTER);
+    System.out.println("Encrypted token is: " + encryptedToken);
+
+    String decryptedToken = Paseto.decrypt(new SecretKey(secretKey, V3), encryptedToken, FOOTER);
+    System.out.println("Decrypted token is: " + decryptedToken);
+  }
+}