package Ġeu . vaadin on kotlin . security Ċ Ċ import Ġcom . vaadin . flow . server . V aad in Request Ċ import Ġcom . vaadin . flow . server . auth . Access Annotation Checker Ċ import Ġcom . vaadin . flow . server . auth . View Access Checker Ċ import Ġeu . vaadin on kotlin . V aad in On Kotlin Ċ import Ġjava . security . Principal Ċ import Ġjava . util . function . Function Ċ import Ġjavax . servlet . http . HttpServletRequest Ċ Ċ /** Ċ Ġ* ĠComp let ely Ġby passes Ġthe ĠServlet ĠContainer Ġsecurity . ĠInstead Ġof Ġchecking Ġthe Ġoutcome Ġof Ċ Ġ* Ġ[ HttpServletRequest . getUser Principal ] Ġand Ġ[ HttpServletRequest . is User In Role ], Ċ Ġ* Ġit Ġchecks Ġthe Ġ[ V aad in On Kotlin . logged In User Resolver ] Ġinstead . Ċ Ġ*/ Ċ public Ġobject ĠV ok Access Annotation Checker Ġ: ĠAccess Annotation Checker () Ġ{ ĊĠĠĠ Ġoverride Ġfun Ġhas Access ( ĊĠĠĠĠĠĠĠ Ġcls : ĠClass <* >, ĊĠĠĠĠĠĠĠ Ġrequest : ĠHttpServletRequest ĊĠĠĠ Ġ): ĠBoolean Ġ{ ĊĠĠĠĠĠĠĠ Ġval Ġuser Resolver : ĠLog ged In User Resolver Ġ= ĠV aad in On Kotlin . logged In User Resolver ĊĠĠĠĠĠĠĠ Ġreturn Ġhas Access ( cls , Ġuser Resolver . getCurrent User ()) Ġ{ Ġrole Ġ-> Ġuser Resolver . has Role ( role ) Ġ} ĊĠĠĠ Ġ} Ċ } Ċ Ċ /** Ċ Ġ* ĠChecks Ġthat Ġa Ġuser Ġis Ġlogged Ġin . ĠUses Ġstandard ĠV aad in Ġ[ View Access Checker ] Ġbut Ċ Ġ* Ġobt ains Ġthe Ġuser Ġfrom Ġ[ V aad in On Kotlin . logged In User Resolver ] Ġrather Ġthan Ġfrom Ċ Ġ* Ġ[ HttpServletRequest . getUser Principal ] Ġand Ġ[ HttpServletRequest . is User In Role ]. Ċ Ġ* Ċ Ġ* Ġ* ĠDon 't Ġforget Ġto Ġinstall Ġa Ġproper Ġ[ V aad in On Kotlin . logged In User Resolver ] Ġfor Ġyour Ġproject . Ċ Ġ* Ġ* ĠInstall Ġthis Ġas Ġa Ġ[ com . vaadin . flow . router . Before Enter Listener ] Ġinto Ġyour ĠUI , Ċ Ġ* ĠĠ Ġusually Ġvia Ġthe Ġ[ com . vaadin . flow . server . V aad in Service Init Listener ]. Ċ Ġ* Ċ Ġ* ĠSee Ġ[ v ok - security ĠREADME ]( https :// github . com / mv ys ny / vaadin - on - kotlin / blob / master / v ok - security / README . md ) Ċ Ġ* Ġon Ġhow Ġto Ġuse Ġthis Ġclass Ġproperly . Ċ Ġ*/ Ċ public Ġclass ĠV ok View Access Checker Ġ: ĠView Access Checker ( V ok Access Annotation Checker ) Ġ{ ĊĠĠĠ Ġinit Ġ{ ĊĠĠĠĠĠĠĠ Ġenable () ĊĠĠĠ Ġ} ĊĊĠĠĠ Ġ// ĠV aad in Ġ 2 3 . 0 . x Ġuses ĠAccess Annotation Checker Ġto Ġget Ġprincipal . ĊĠĠĠ Ġ// ĠV aad in Ġ 2 3 . 1 . 0 Ġretrieves Ġthe Ġprincipal Ġthis Ġway . ĊĠĠĠ Ġoverride Ġfun Ġget Principal ( request : ĠV aad in Request ?): ĠPrincipal ? Ġ= ĠV aad in On Kotlin . logged In User Resolver . getCurrent User () ĊĠĠĠ Ġoverride Ġfun Ġget Roles Checker ( request : ĠV aad in Request ?): ĠFunction < String , ĠBoolean > Ġ= ĠFunction Ġ{ Ġrole Ġ-> ĊĠĠĠĠĠĠĠ ĠV aad in On Kotlin . logged In User Resolver . getCurrent User Roles (). contains ( role ) ĊĠĠĠ Ġ} Ċ } Ċ