api/app.go
func revokeAppAccess(w http.ResponseWriter, r *http.Request, t auth.Token) (err error) {
	appName := r.URL.Query().Get(":app")
	teamName := r.URL.Query().Get(":team")
	a, err := getAppFromContext(appName, r)
	if err != nil {
		return err
	}
	allowed := permission.Check(t, permission.PermAppUpdateRevoke,
		contextsForApp(&a)...,
	)
	if !allowed {
		return permission.ErrUnauthorized
	}
	evt, err := event.New(&event.Opts{
		Target:     appTarget(appName),
		Kind:       permission.PermAppUpdateRevoke,
		Owner:      t,
		CustomData: event.FormToCustomData(InputFields(r)),
		Allowed:    event.Allowed(permission.PermAppReadEvents, contextsForApp(&a)...),
	})
	if err != nil {
		return err
	}
	defer func() { evt.Done(err) }()
	team, err := servicemanager.Team.FindByName(teamName)
	if err != nil || team == nil {
		return &errors.HTTP{Code: http.StatusNotFound, Message: "Team not found"}
	}
	if len(a.Teams) == 1 {
		msg := "You can not revoke the access from this team, because it is the unique team with access to the app, and an app can not be orphaned"
		return &errors.HTTP{Code: http.StatusForbidden, Message: msg}
	}
	err = a.Revoke(team)
	switch err {
	case app.ErrNoAccess:
		return &errors.HTTP{Code: http.StatusNotFound, Message: err.Error()}
	case app.ErrCannotOrphanApp:
		return &errors.HTTP{Code: http.StatusForbidden, Message: err.Error()}
	default:
		return err
	}
}
func revokeAppAccess(w http.ResponseWriter, r *http.Request, t auth.Token) (err error) {
	appName := r.URL.Query().Get(":app")
	teamName := r.URL.Query().Get(":team")
	a, err := getAppFromContext(appName, r)
	if err != nil {
		return err
	}
	allowed := permission.Check(t, permission.PermAppUpdateRevoke,
		contextsForApp(&a)...,
	)
	if !allowed {
		return permission.ErrUnauthorized
	}
	evt, err := event.New(&event.Opts{
		Target:     appTarget(appName),
		Kind:       permission.PermAppUpdateRevoke,
		Owner:      t,
		CustomData: event.FormToCustomData(InputFields(r)),
		Allowed:    event.Allowed(permission.PermAppReadEvents, contextsForApp(&a)...),
	})
	if err != nil {
		return err
	}
	defer func() { evt.Done(err) }()
	team, err := servicemanager.Team.FindByName(teamName)
	if err != nil || team == nil {
		return &errors.HTTP{Code: http.StatusNotFound, Message: "Team not found"}
	}
	if len(a.Teams) == 1 {
		msg := "You can not revoke the access from this team, because it is the unique team with access to the app, and an app can not be orphaned"
		return &errors.HTTP{Code: http.StatusForbidden, Message: msg}
	}
	err = a.Revoke(team)
	switch err {
	case app.ErrNoAccess:
		return &errors.HTTP{Code: http.StatusNotFound, Message: err.Error()}
	case app.ErrCannotOrphanApp:
		return &errors.HTTP{Code: http.StatusForbidden, Message: err.Error()}
	default:
		return err
	}
}
// title: revoke access to app
// path: /apps/{app}/teams/{team}
// method: DELETE
// responses:
//   200: Access revoked
//   401: Unauthorized
//   403: Forbidden
//   404: App or team not found