微信小程序登录

微信小程序登录，获取用户手机号

基础类

<dependency>
      <groupId>org.bouncycastle</groupId>
      <artifactId>bcprov-jdk15on</artifactId>
      <version>1.57</version>
</dependency>

@Data
@AllArgsConstructor
@NoArgsConstructor
public class WeiXinLoginVo {
    private String openId;
    private String session_key;
    private String unionid;
    private Integer errcode;
    private String errmsg;
}

/**
* 向指定 URL 发送GET方法的请求
*
* @param url   发送请求的 URL
* @param param 请求参数，请求参数应该是 name1=value1&name2=value2 的形式。
* @return 所代表远程资源的响应结果
*/
public static String sendGet(String url, String param) {
    StringBuilder result = new StringBuilder();
    BufferedReader in = null;
    try {
        String urlNameString = url;
        if (param != null) {
            urlNameString = url + "?" + param;
        }
        URL realUrl = new URL(urlNameString);
        URLConnection connection = realUrl.openConnection();
        connection.setRequestProperty("accept", "*/*");
        connection.setRequestProperty("connection", "Keep-Alive");
        connection.setRequestProperty("user-agent", "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1;SV1)");
        connection.connect();
        in = new BufferedReader(new InputStreamReader(connection.getInputStream()));
        String line;
        while ((line = in.readLine()) != null) {
            result.append(line);
        }
    } catch (Exception e) {
        e.printStackTrace();
    } finally {
        try {
            if (in != null) {
                in.close();
            }
        } catch (Exception ex) {
            ex.printStackTrace();
        }
    }
    return result.toString();
}

获取前端传入的code调用接口获取session_key

// 小程序 appId
@Value("${weixin.appid}")
private String appid;
// 小程序 appSecret
@Value("${weixin.secret}")
private String secret;

public WeiXinLoginVo goLogin(String code) {
    String url = "https://api.weixin.qq.com/sns/jscode2session?appid=" + appid + "&secret=" + secret + "&js_code=" + jsCode + "&grant_type=authorization_code";
    String result = HttpUtils.sendGet(url, null);
    return JSON.parseObject(result, WeiXinLoginVo.class);
}

解密前端传入的encryptedData和iv

// 传入sessionKey和其他两个数据
weiXinCommon.decryptOfDiyIV(userLoginVo.getEncryptedData(), sessionKey, userLoginVo.getIv());

private static final String KEY_ALGORITHM = "AES";
private static final String ALGORITHM_STR = "AES/CBC/PKCS7Padding";
private static Key key;
private static Cipher cipher;
/**
* 解密方法
*
* @param encryptedData 要解密的字符串
* @param sessionKeyB64      解密密钥
* @param ivs           自定义对称解密算法初始向量 iv
* @return 解密后的字节数组
*/
public byte[] decryptOfDiyIV(String encryptedData, String sessionKeyB64, String ivs) {
    byte[] encryptedDataByte = Base64.decode(encryptedData);
    byte[] sessionKeyB64Byte = Base64.decode(sessionKeyB64);
    byte[] ivsByte = Base64.decode(ivs);
    byte[] encryptedText = null;
    init(sessionKeyB64Byte);
    try {
        cipher.init(Cipher.DECRYPT_MODE, key, new IvParameterSpec(ivsByte));
        encryptedText = cipher.doFinal(encryptedDataByte);
    } catch (Exception e) {
        e.printStackTrace();
    }
    return encryptedText;
}

private void init(byte[] keyBytes) {
    // 如果密钥不足16位，那么就补足.  这个if 中的内容很重要
    int base = 16;
    if (keyBytes.length % base != 0) {
        int groups = keyBytes.length / base + (keyBytes.length % base != 0 ? 1 : 0);
        byte[] temp = new byte[groups * base];
        Arrays.fill(temp, (byte) 0);
        System.arraycopy(keyBytes, 0, temp, 0, keyBytes.length);
        keyBytes = temp;
    }
    // 初始化
    Security.addProvider(new BouncyCastleProvider());
    // 转化成JAVA的密钥格式
    key = new SecretKeySpec(keyBytes, KEY_ALGORITHM);
    try {
        // 初始化cipher
        cipher = Cipher.getInstance(ALGORITHM_STR, "BC");
    } catch (Exception e) {
        e.printStackTrace();
    }
}