JAVASCRIPT

Tableau JS api getdata

        function getUnderlyingData() {
            sheet = viz.getWorkbook().getActiveSheet().getWorksheets().get("By Weekly");
            // If the active sheet is not a dashboard, then you can just enter:
            // viz.getWorkbook().getActiveSheet();
            options = {
                maxRows: 10, // Max rows to return. Use 0 to return all rows
                ignoreAliases: false,
                ignoreSelection: true,
                includeAllColumns: false
            };

            sheet.getSummaryDataAsync(options).then(function(t) {
                table = t;
                var tgt = document.getElementById("dataTarget");
                tgt.innerHTML = "<h4>Underlying Data:</h4><p>" + JSON.stringify(table.getData()) + "</p>";
            });
        }