topic Python API add group layer to webmap? in ArcGIS API for Python Questions

Python API add group layer to webmap?

RichardReinicke — Thu, 28 Oct 2021 14:58:44 GMT

map_item["operationalLayers"]

Hi,

I have a very general question this time.

The Esri arcgis API is meant to be THE tool to automate workflows and to interact with ArcGIS Portal. But there seem to be a lot of features that are not implemented yet, in my case map authorization.

I have the new webmaps (next gen) and map viewer beta. I can interact with web maps v2 also from the Python API. But I can't create a group layer with API methods.

I can do:

map_item.get_data()

I see my GroupLayer in the map layers:

map_item["operationalLayers"]

[ { "id": "htsews6tyu0-layer-10010", "title": "DummyGroup", "layers": [ { "id": "17cc733308b-layer-3", "title": "FeatureLayer1", "url": "some-feature-server-url", "itemId": "d77d046fb6de424da2258a08b376f1fc", "layerType": "ArcGISFeatureLayer", "popupInfo": { "popupElements": [ { "type": "fields" } ], "showAttachments": True, "fieldInfos": [ { "fieldName": "objectid", "label": "OBJECTID", "visible": False } ], "title": "Titel1" } }, { "id": "17cc7332022-layer-2", "title": "FeatureLayer2", "url": "some-feature-server-url", "itemId": "3efe6ee7327e49e59a37406f622db492", "layerType": "ArcGISFeatureLayer", "popupInfo": { "popupElements": [ { "type": "fields" } ], "showAttachments": True, "fieldInfos": [ { "fieldName": "objectid", "label": "OBJECTID", "visible": False } ], "title": "Titel2" } } ], "layerType": "GroupLayer" } ]

Now I can get portal Feature Service items and it's FeatureLayer items and I want to:
1. add another Feature Layer to map_item["operationalLayers"][0]["layers"]

2. or add another group layer with x feature layers

We really need operations for the Python API to compose a webmap and its layers from existing layer items.

Re: Python API add group layer to webmap?

RichardReinicke — Fri, 29 Oct 2021 08:41:58 GMT

I've been able now to accomplish my goal and to add a new group layer with existing feature layers to my web map item. Unfortunatly for this you need to write dictionaries that correspond to Esri web map specification (GroupLayer, FeatureLayer ... )
https://developers.arcgis.com/web-map-specification/objects/groupLayer/

Here are the major parts:

def create_layer_id(layerIndex): return ''.join(random.choices(string.ascii_lowercase + \ string.digits, k=11)) + "-layer-" + str(layerIndex) # This is my base webmap (template) map_template = gis.content.get('3095cb51e2a44e818b90608c487f8b3b') # Copy template to new web map item into subfolder project_map = WebMap(map_template).save({ "title": "project map", "snippet": "some description", "tags": "maps"}, folder="project_folder") # Create a new group layer following esri web map specification group_layer = { "id": create_layer_id(random.randint(10000, 99999)), "layers": [], "layerType": "GroupLayer", "title": "my new group layer" } # Get an existing feature service / layer collection item # get_item() is standard portal item query logic lyr_item = get_item(lyr_name, "Feature Service", "test") # Create feature layer following esri web map specification feature_layer = { "id": create_layer_id(random.randint(10000, 99999)), "url": lyr_item.layers[0].url, "title": lyr_item.layers[0].properties.name, "itemId": lyr_item.id, "layerType": "ArcGISFeatureLayer" } # Add feature layer to group layer group_layer["layers"].append(feature_layer ) # Update project map with new group layer map_def = project_map.get_data() map_def["operationalLayers"].append(group_layer) project_map.update({'text': str(map_def)})

Maybe this will help someone 🙂

Re: Python API add group layer to webmap?

Scoth — Tue, 11 Jul 2023 14:36:32 GMT

Do you know if the layer id has to be unique? If so, it seems like the randint function wouldn't be the best option, even though it will probably work.