wechat redirect

WechatRedirectController.kt

    val OAUTH2_URL = "https://open.weixin.qq.com/connect/oauth2/authorize?appid=APPID&redirect_uri=REDIRECTURI&response_type=code&scope=SCOPE&state=STATE#wechat_redirect"
    val appId = "xxxx"

    /**
     * 认证
     * @param url 回跳链接
     * @param scope 授权方式
     */
    @GetMapping("/getCode")
    fun redirect(url: String, scope: String, response: HttpServletResponse) {
        val encodedUrl = encode(url, StandardCharsets.UTF_8)
        val redirectUrl: String = OAUTH2_URL
                .replace("APPID", appId)
                .replace("REDIRECTURI", encode("http://www.xxx.com/redirectBack?url=$encodedUrl", StandardCharsets.UTF_8))
                .replace("SCOPE", scope)
        response.sendRedirect(redirectUrl)
    }

    /**
     * 回跳
     * @param url 回跳链接
     * @param code 授权code
     */
    @GetMapping("/redirectBack")
    fun redirectBack(url: String, response: HttpServletResponse, code: String) {
        val redirectUrl = url + (if (url.contains("?")) "&" else "?") + "code=$code"
        response.sendRedirect(redirectUrl)
    }