Does anyone know if there is a tool that can generate a report of what webmaps and apps use a selected layer/service? Something that works both for enterprise portal and ArcGIS Online? I have tried qonda, ArcGIS Online Assistant, and Admin Tools for ArcGIS Online to no avail. Surely there must be something out there?
In Enterprise, there are properties dependent_to and dependent_upon, which are, sadly, not available in AGOL just yet.
However, you can manually loop through your web maps and look for those dependencies in a Python Notebook. If you know the itemID of the service(s) you want to look up, you can use something like the code below:
from arcgis.gis import GIS from arcgis.mapping import WebMap service_ids = ['list', 'of', 'itemIDs'] webmaps = gis.content.search('', item_type='Web Map', max_items=-1) map_list =  for w in webmaps: wm = WebMap(w) for b in wm.basemap.baseMapLayers: try: b.itemId except AttributeError: continue else: if b.itemId in service_ids: map_list.append(w) for l in wm.layers: try: l.itemId except AttributeError: continue else: if l.itemId in service_ids: map_list.append(w)
This will look at each layer in each web map, adding the web map to the map_list list if any of the layers match the input itemID(s).