In the docs it says:
" You may add one or more layer items to compose a web map or web scene item. Whenever you perform such an operation, you establish a relationship between the items."
I take this to mean that each web map should have a relationship to any layers that have been added to it.
However it seems that if I try to check a map that has a single feature layer, and a publicly hosted basemap I always get the following error for both dependent_to() and dependent_upon() methods:
Unable to get dependents to: 2f1071ac3228427289a6e03d2b625995 Unable to retrieve item dependents.
When I try
It returns an empty array/list.
What are the limitations of these methods? Do they not work if any of the layers are hosted on a public ArcGIS Server? How about an ArcGIS Server that has security setup?
I tried dependent_to on several feature layers and also received the same error.
I'm also running into this error message when attempting to map out relationship between portal items, in this case a web map and a layers in the map.
returns an empty array
While running the dependent_upon or dependent_to methods returns:
Unable to get dependencies for item: item# Unable to retrieve item dependencies. --------------------------------------------------------------------------- RuntimeError Traceback (most recent call last) <ipython-input-3-2b1d726173d1> in <module>() ----> 1 zoningItem.dependent_upon() /opt/conda/lib/python3.5/site-packages/arcgis/gis.py in dependent_upon(self) 2993 def dependent_upon(self): 2994 """ Returns items and urls, etc that this items depends upon """ -> 2995 return self._portal.get_item_dependencies(self.itemid) 2996 2997 def dependent_to(self): /opt/conda/lib/python3.5/site-packages/arcgis/_impl/portalpy.py in get_item_dependencies(self, itemid) 1124 1125 def get_item_dependencies(self, itemid): -> 1126 return self.con.post('content/items/' + itemid + '/dependencies', self._postdata()) 1127 1128 def get_item_dependents_to(self, itemid): /opt/conda/lib/python3.5/site-packages/arcgis/_impl/connection.py in post(self, path, postdata, files, ssl, compress, is_retry, use_ordered_dict, add_token, verify_cert, token) 954 elif errorcode == 498: 955 raise RuntimeError('Invalid token') --> 956 self._handle_json_error(resp_json['error'], errorcode) 957 return None 958 except AttributeError: /opt/conda/lib/python3.5/site-packages/arcgis/_impl/connection.py in _handle_json_error(self, error, errorcode) 974 975 errormessage = errormessage + "\n(Error Code: " + str(errorcode) +")" --> 976 raise RuntimeError(errormessage) 977 978 class _StrictURLopener(request.FancyURLopener): RuntimeError: Unable to get dependencies for item: item# Unable to retrieve item dependencies. (Error Code: 500)
I spoke with an ESRI staffer at the UC last summer and he clarified that item relationships must be declared for each item in the portal. I think that would explain the errors mentioned above. I thought that behind the scenes ESRI was graphing the item dependencies and exposing them via the relationship method but that appears to not be the case.
They make very little mention of needing to establish these relationships. It is implied in the documentation that for Web Map Items in particular it is done in the background. I only get empty results on any of the three methods.