Ao tentar usar o WCMAPI em evento global beforedocumentviewer

recebo o erro WCMAPI is not defined

function beforeDocumentViewer(){ 

    //Informações do documento
    var doc = getValue("WKDocument");
    //var versao= getValue("WKNumVersion");
    log.info("INFODEV beforedocumentviewer "+ doc.documentId);
    try { 
        var c1 = DatasetFactory.createConstraint( "idarquivo", doc.documentId, doc.documentId, ConstraintType.MUST); 
        var constraints = new Array(c1); 
        var ds = DatasetFactory.getDataset("ds_leitura_obrigatoria", null, constraints, null); 
    }catch (e) {
        log.error("Erro ao tentar atualizar a leitura do documento : " + e.message); 
    } 

    log.info("INFODEV beforedocumentviewer "+ ds.length);
    ds.values.forEach(function(item, index){

        dados = '[{"name": "leitura","value": "true"}]';    
        WCMAPI.Create({
            url : "/ecm/api/rest/ecm/cardView/editCard/"+this.documentid+"/"+this.version,
            method : "POST",
            contentType: "application/json",
            dataType: "json",
            data : dados,
            success : function(data) {
                log.info("*****sucesso*****");
            },
            error : function(data, errorThrown, status) {
                log.info("*****erro***** " + status);
            }
        });
    });

}