There is a bug in the Web_Map_as_JSON of the EsriPrintTask. I worked around it by creating my own subclass and walking the layer chain and building the visibility list.
(function (wapp) {
wapp.objects = wapp.objects || {};
require([
"esri/tasks/PrintTask",
"esri/core/Accessor"
], function (
EsriPrintTask,
Accessor
) {
wapp.objects.CustomPrintTask = EsriPrintTask.createSubclass({
execute: function (a, b) {
internalPrintPrams = this._setPrintParams(a);
// parse current esri version
var mapJson = JSON.parse(internalPrintPrams.Web_Map_as_JSON);
// add rotation
mapJson.mapOptions.rotation = -1 * a.view.rotation;
// Force scale
mapJson.mapOptions.scale = a.view.scale;
// create visibleLayers node
$(mapJson.operationalLayers).each(function (opIdx, opLayer) {
var visibleLayers = [];
$(opLayer.layers).each(function (subIdx, subLayer) {
visibleLayers.push(subLayer.id);
});
opLayer.visibleLayers = jQuery.makeArray(visibleLayers);
})// for each Operational Layer
// Remove empty layers
mapJson.operationalLayers = jQuery.grep(mapJson.operationalLayers, function (layer, idx) {
return ((layer.visibleLayers.length > 0)
|| ((layer.featureCollection) && (layer.featureCollection.layers) && (layer.featureCollection.layers.length > 0)));
}); // grep Operational Layers
// Add "style": "esriSMSCircle", to draw features that don't have it
jQuery.each(mapJson.operationalLayers, function (opIdx, opLayer) {
if ((opLayer.featureCollection)&&(opLayer.featureCollection.layers) && (opLayer.featureCollection.layers.length > 0)) {
jQuery.each(opLayer.featureCollection.layers, function (featureSetIdx, featureSet) {
jQuery.each(featureSet.featureSet.features, function (featureIdx, feature) {
if ((feature.symbol)&&(!feature.symbol.style)) {
feature.symbol.style = "esriSMSCircle";
}
}); // for each featureSet
});
}
}); // for each opLayer, add style to symbols that don't have it
internalPrintPrams.Web_Map_as_JSON = JSON.stringify(mapJson);
return this._geoprocessor["async" === this.mode ? "submitJob" : "execute"](internalPrintPrams, b)
.then(this._handleExecuteResponse)
}
});
}); // require
}(window.wapp = window.wapp || {}));
