Add PKCEUtils.java

src/main/java/com/monkeyk/sos/infrastructure/PKCEUtils.java

@@ -0,0 +1,56 @@
+package com.monkeyk.sos.infrastructure;
+
+import org.apache.commons.lang3.RandomStringUtils;
+
+import java.nio.charset.StandardCharsets;
+import java.security.MessageDigest;
+import java.security.NoSuchAlgorithmException;
+import java.util.Base64;
+
+/**
+ * 2023/10/16 22:45
+ * <p>
+ * PKCE tool:
+ *
+ * @author Shengzhao Li
+ * @since 3.0.0
+ */
+public abstract class PKCEUtils {
+
+    private static final String ALG = "SHA-256";
+
+
+    private PKCEUtils() {
+    }
+
+    /**
+     * 随机生成32的 code_verifier
+     *
+     * @return code_verifier
+     */
+    public static String generateCodeVerifier() {
+        // 1. 随机生成code_verifier
+        String codeVerifierVal = RandomStringUtils.random(32, true, true);
+        //2. 对 code_verifier 进行base64 encode
+        return Base64.getEncoder().encodeToString(codeVerifierVal.getBytes(StandardCharsets.UTF_8));
+    }
+
+    /**
+     * 根据指定的 code_verifier 计算 code_challenge
+     *
+     * @param codeVerifier code_verifier
+     * @return code_challenge
+     */
+    public static String generateCodeChallenge(String codeVerifier) {
+        MessageDigest md;
+        try {
+            md = MessageDigest.getInstance(ALG);
+        } catch (NoSuchAlgorithmException e) {
+            throw new IllegalStateException("JDK not found alg: '" + ALG + "' ??", e);
+        }
+        byte[] digest = md.digest(codeVerifier.getBytes(StandardCharsets.US_ASCII));
+        return Base64.getUrlEncoder().withoutPadding().encodeToString(digest);
+    }
+
+
+}

src/test/java/com/monkeyk/sos/infrastructure/PKCEUtilsTest.java

@@ -0,0 +1,65 @@
+package com.monkeyk.sos.infrastructure;
+
+import org.apache.commons.lang3.RandomStringUtils;
+import org.junit.jupiter.api.Test;
+
+import java.nio.charset.StandardCharsets;
+import java.security.MessageDigest;
+import java.util.Base64;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+/**
+ * 2023/10/16 22:53
+ *
+ * @author Shengzhao Li
+ * @since 3.0.0
+ */
+class PKCEUtilsTest {
+
+
+    @Test
+    void generateCodeVerifier() {
+
+        String verifier = PKCEUtils.generateCodeVerifier();
+        assertNotNull(verifier);
+        assertTrue(verifier.length() >= 32);
+    }
+
+
+    @Test
+    void generateCodeChallenge() {
+
+        String verifier = PKCEUtils.generateCodeVerifier();
+        assertNotNull(verifier);
+
+        String challenge = PKCEUtils.generateCodeChallenge(verifier);
+        assertNotNull(challenge);
+
+    }
+
+
+    /**
+     * PKCE 需要的参数生成测试
+     * code_challenge_method : S256   (alg: SHA-256)  固定值
+     * code_verifier :  随机生成且base64 encode的值 （推荐随机值至少32位）
+     * code_challenge :   对 code_verifier 使用指定算法进行计算(digest)并base encode的值
+     *
+     * @throws Exception e
+     */
+    @Test
+    void pkceFlow() {
+
+        // 1. 随机生成code_verifier
+        String codeVerifier = PKCEUtils.generateCodeVerifier();
+//        System.out.println("code_verifier -> " + codeVerifier);
+
+        //2. 按指定算法计算 挑战码 code_challenge
+        String codeChallenge = PKCEUtils.generateCodeChallenge(codeVerifier);
+
+        assertNotNull(codeChallenge);
+//        System.out.println("code_challenge -> " + codeChallenge);
+    }
+
+
+}