# Name: Directions_Workflow.py
# Description: Generate driving directions in an html file for a route that
# visits the store locations in the best sequence in order to
# minimize the total travel time
# Requirements: Network Analyst Extension
#Import system modules
import arcpy
from arcpy import env
import os
try:
#Check out Network Analyst license if available. Fail if the Network Analyst license is not available.
if arcpy.CheckExtension("network") == "Available":
arcpy.CheckOutExtension("network")
else:
raise arcpy.ExecuteError("Network Analyst Extension license is not available.")
#Set environment settings
output_dir = "C:/Data"
#The NA layer's data will be saved to the workspace specified here
env.workspace = os.path.join(output_dir, "Output.gdb")
env.overwriteOutput = True
#Set inputs and outputs
input_gdb = "C:/Data/SanFrancisco.gdb"
network = os.path.join(input_gdb, "Transportation", "Streets_ND")
layer_name = "StoreRoute"
travel_mode = "Driving Time"
start_location = os.path.join(input_gdb, "Analysis", "DistributionCenter")
store_locations = os.path.join(input_gdb, "Analysis", "Stores")
output_directions = os.path.join(output_dir,
layer_name + "_Directions.html")
output_layer_file = os.path.join(output_dir, layer_name + ".lyrx")
#Create a new route layer. The route starts at the distribution center and
#visits the stores in the best order to yield the shortest travel time.
result_object = arcpy.na.MakeRouteAnalysisLayer(network, layer_name,
travel_mode, "PRESERVE_FIRST",
time_of_day="8:00 AM")
#Get the layer object from the result object. The route layer can
#now be referenced using the layer object.
layer_object = result_object.getOutput(0)
#Get the names of all the sublayers within the route layer.
sublayer_names = arcpy.na.GetNAClassNames(layer_object)
#Stores the layer names that we will use later
stops_layer_name = sublayer_names["Stops"]
#Load the distribution center as the start location using default field
#mappings and search tolerance
arcpy.na.AddLocations(layer_object, stops_layer_name, start_location, "",
"")
#Load the store locations as stops. Make sure the store locations are
#appended to the Stops sublayer so the distribution center you just loaded
#isn't overwritten. Map the ServiceTime field from the input data to the
#Attr_[impedance] property in the Stops sublayer so that the time it takes to
#service each store is included in the total travel time for the route.
#Figure out what the impedance attrbute is
solver_props = arcpy.na.GetSolverProperties(layer_object)
impedance = solver_props.impedance
#Handle field mappings
field_mappings = arcpy.na.NAClassFieldMappings(layer_object,
stops_layer_name)
field_mappings["Name"].mappedFieldName = "Name"
field_mappings["Attr_" + impedance].mappedFieldName = "ServiceTime"
arcpy.na.AddLocations(layer_object, stops_layer_name, store_locations,
field_mappings, "", append="APPEND",
exclude_restricted_elements = "EXCLUDE")
#Generate driving directions in an HTML file
arcpy.na.Directions(layer_object, "HTML", output_directions, "Miles",
"REPORT_TIME", impedance)
#Save the solved na layer as a layer file on disk
layer_object.saveACopy(output_layer_file)
print("Script completed successfully")
except Exception as e:
# If an error occurred, print line number and error message
import traceback, sys
tb = sys.exc_info()[2]
print("An error occurred on line %i" % tb.tb_lineno)
print(str(e))