CRM 2011: Using FetchXML with JavaScript to check for a user privilege client side

I recently had the need to perform a client side check if a user had Create privilege on the Account entity.  I knew it should be simple to create a FetchXML query to find this information, so all I needed was to execute this FetchXML query from the form.   There are a number of handy JavaScript libraries to to execute FetchXML and I decided to go with the XrmSvcToolkit.

So here is my new FetchXML privilege check function using the XrmSvcToolkit.

function HasUserPrivilage(UserId, PrivilageName) {

    var hasPrivilege = false;

    var fetchXml = "<fetch mapping='logical' version='1.0'>"

            + "<entity name='privilege'>"

            + "<attribute name='accessright' />"

            + "<attribute name='name' />"

            + "<filter>"

            + "<condition attribute='name' operator='eq' value='" + PrivilageName + "' />"

            + "</filter>"

            + "<link-entity name='roleprivileges' from='privilegeid' to='privilegeid'>"

            + "<link-entity name='role' from='parentrootroleid' to='roleid'>"

            + "<link-entity name='systemuserroles' from='roleid' to='roleid'>"

            + "<filter>"

            + "<condition attribute='systemuserid' operator='eq' value='" + UserId + "' />"

            + "</filter>"

            + "</link-entity>"

            + "</link-entity>"

            + "</link-entity>"

            + "</entity>"

            + "</fetch>";

    XrmSvcToolkit.fetch({

        fetchXml: fetchXml,

        async: false,

        successCallback: function (result) {

            if (result.entities.length > 0) {

                hasPrivilege = true;

            } else {

                hasPrivilege = false;

            }

        },

        errorCallback: function (error) {

            throw error;

        }

    });

    return hasPrivilege;

}

And usage

HasUserPrivilage(Xrm.Page.context.getUserId(), "prvCreateAccount");