Place a layer from a geodatabase onto an ArcGIS Pro map using a Python script

Summary

Features are added to the map for visualization when performing any process in ArcGIS Pro. When added to an opened map, these features are automatically converted into a layer file. For a feature in a geodatabase to be added to a map using a Python script, the feature must be converted into a layer file. Therefore to place a feature onto a map without opening the ArcGIS Pro software, the Make Feature Layer and Save To Layer File tools are used in the script to convert the desired feature from a geodatabase into a layer file.

The following workflow describes how to add features to an existing map using a Python script.

Procedure

1. Import the necessary modules.

import arcpy

2. Specify the workspace and the ArcGIS Project file location.

arcpy.env.workspace = r"<folder_location>\<geodatabase.gdb>"

project_path = r"<folder_location>\<project_name.aprx>"
aprx = arcpy.mp.ArcGISProject(project_path)

3. Specify the parameters to be used in the Make Feature Layer and Save To Layer File tools.

layer = r"<folder_location>\<geodatabase.gdb>\<file_name>"
layers_out = "<output_file_name>"
output_location = r"<folder_location>\{}.lyrx".format(layers_out) #Same as project path

4. Call the Make Feature Layer and Save To Layer File tools.

arcpy.management.MakeFeatureLayer(in_layer, "<output_file_name>")
arcpy.management.SaveToLayerFile("<output_file_name>" , layers_out)

5. Insert the layer into the map in reference to an existing layer.

insertLyr = arcpy.mp.LayerFile(output_location)
m = aprx.listMaps("*")[0]
refLyr = m.listLayers("file_name")[0]
m.insertLayer(refLyr, insertLyr, "BEFORE")

6. Save the project file.

aprx.save()

7. Clear the lock file of the project.

del aprx

The code block below demonstrates the full script.

import arcpy

arcpy.env.workspace = r"C:\USER\Desktop\Test\test.gdb"

project_path = r"C:\USER\Desktop\Test\Test_Project.aprx"
aprx = arcpy.mp.ArcGISProject(project_path)

layer = r"C:\USER\Desktop\Test\test.gdb\Layer_Test" #The feature name in the geodatabase
layers_out = "Layer_Test" #The file name for the output layer
output_location = r"C:\USER\Desktop\Test\{}.lyrx".format(layers_out)

arcpy.management.MakeFeatureLayer(in_layer, "Layer_Test")
arcpy.management.SaveToLayerFile("Layer_Test" , layers_out)

insertLyr = arcpy.mp.LayerFile(output_location)
m = aprx.listMaps("*")[0]
refLyr = m.listLayers("Existing_Layer")[0]
m.insertLayer(refLyr, insertLyr, "BEFORE") #Insert the new layer onto the map before the specified existing layer

aprx.save()

del aprx #Close the project and delete the lock file