接着上一篇的play framework cors跨域、继续讲jwt在play framework中怎么使用的、什么是jwt？JSON Web Token (JWT)是一个开放标准(RFC 7519)，它定义了一种紧凑的、自包含的方式，用于作为JSON对象在各方之间安全地传输信息。该信息可以被验证和信任，因为它是数字签名的。

简单来说、用了它、你就再也不用在程序中管理全局session会话了。

使用教程

application.conf添加配置

play.http.secret.key = "hello"
# 线上记得修改、默认是changeme
session = {

  # The cookie name
  cookieName = "PLAY_SESSION"

  # Whether the secure attribute of the cookie should be set to true
  secure = false

  # The max age to set on the cookie.
  # If null, the cookie expires when the user closes their browser.
  # An important thing to note, this only sets when the browser will discard the cookie.
  maxAge = null

  # Whether the HTTP only attribute of the cookie should be set to true
  httpOnly = true

  # The value of the SameSite attribute of the cookie. Set to null for no SameSite attribute.
  # Possible values are "lax" and "strict". If misconfigured it's set to null.
  sameSite = "lax"

  # The domain to set on the session cookie
  # If null, does not set a domain on the session cookie.
  domain = null

  # The session path
  # Must start with /.
  path = ${play.http.context}

  jwt {
    # The JWT signature algorithm to use on the session cookie
    # uses 'alg' https://tools.ietf.org/html/rfc7515#section-4.1.1
    signatureAlgorithm = "HS256"

    # The time after which the session is automatically invalidated.
    # Use 'exp' https://tools.ietf.org/html/rfc7519#section-4.1.4
    expiresAfter = ${play.http.session.maxAge}

    # The amount of clock skew to accept between servers when performing date checks
    # If you have NTP or roughtime synchronizing between servers, you can enhance
    # security by tightening this value.
    clockSkew = 5 minutes

    # The claim key under which all user data is stored in the JWT.
    dataClaim = "data"
  }
}

使用、例如用户登录成功就可以像下面一样使用

Ok(Json.obj(
                "code" -> "success",
                "msg" -> "登录成功",
                "data" -> Json.obj(
                  "id" -> resultSet.getString("id"),
                  "nickName" -> resultSet.getString("nickName")
                )
              )).withSession(
                "authorId" -> resultSet.getString("id")
              )

验证的时候就可以像下面一样使用

def create: Action[AnyContent] = Action {
    request =>
      val authorId = request.session.get("authorId")
      if (authorId.isDefined) {
        val data = request.body.asJson
        val result = Json.obj("name" -> "你好")
        Ok(result)
      } else BadRequest(Json.obj("code" -> "failed", "msg" -> "请登录后再操作"))

  }

还可以自定义解析如加密数据、用于ajax请求

@Singleton
class UserController @Inject()(jwt: SessionCookieBaker


def validToken: Action[AnyContent] = Action {
    request =>
      val tokenOption = request.headers.get("token")
      val infos = jwt.decode(tokenOption.get)
      if (infos.isEmpty) {
        BadRequest(Json.obj("code" -> "failed", "msg" -> "用户失效"))
      } else {
        TimeUnit.SECONDS.sleep(1)
        Ok(Json.obj("code" -> "success"))
      }
  }