Access Layer Datasource of a MapService From REST

RamiGhali2 · ‎04-08-2015

Hello,

I have a published mapservice. Using Javascript APIs, I want to get the datasource (Featureclass name) of a specific featurelayer in that mapservice. Is it possible ?

Thanks,

Rami.

RobertScheitlin__GISP · ‎04-08-2015

Rami,

I have wanted to do the same and that information is just not available for the REST endpoint.

RamiGhali2 · ‎04-21-2015

I've come up with the following workaround:

I've created a Python script that can get the datasource of a featurelayer from a mapservice.

Then I've shared this script as a Geoprocessing service that can be consumed via REST or ArcGIS API e.g. ArcGIS API for Javascript.

pythontoolbox

Here is the full script. It's a Python toolbox.

#====================================Python Toolbox===================================

#-------------------------------------------------------------------------------

# Name: GetLayerDataSource

# Purpose: A script that get the dataset name (Full path of the featureclass) of a layer in a map service.

#

# Author: rami.ghali

#

# Created: 20/04/2015

# How to use:

# 1- At [GetLayerDataSource], apply your modifications to set the proper values of the AGS name, port, uname, and password.

# 2- Test the tool

# 3- Share the tool as a geoprocessing service

# 4- Consume the shared Geoprocessing service via ArcGIS API to get the dataset names of layers in a mapservice.

#-------------------------------------------------------------------------------

import arcpy

import httplib, urllib

import json,sys,os

class Toolbox(object):

def __init__(self):

"""Define the toolbox (the name of the toolbox is the name of the

.pyt file)."""

self.label = "GetDataSource"

self.alias = ""

# List of tool classes associated with this toolbox

self.tools = [GetLayerDataSource]

class GetLayerDataSource(object):

def __init__(self):

"""Define the tool (tool name is the name of the class)."""

self.label = "Get Layer DataSource"

self.description = "Get datasource of featurelayer"

self.canRunInBackground = False

def getParameterInfo(self):

"""Define parameter definitions"""

in_mapservice_name = arcpy.Parameter(displayName="Mapservice Name",name="in_mapservice_name",

datatype="String",parameterType="Required",direction="Input")

in_mapservice_name.value = ""

in_layer_names = arcpy.Parameter(displayName="Layer Names",name="in_layer_names",

datatype="String",parameterType="Required",direction="Input")

in_layer_names.value = ""

out_response = arcpy.Parameter(displayName="Response",name="out_response",

datatype="String",parameterType="Derived",direction="Output")

params = [in_mapservice_name,in_layer_names,out_response]

return params

def isLicensed(self):

"""Set whether tool is licensed to execute."""

return True

def updateParameters(self, parameters):

"""Modify the values and properties of parameters before internal

validation is performed. This method is called whenever a parameter

has been changed."""

return

def updateMessages(self, parameters):

"""Modify the messages created by internal validation for each tool

parameter. This method is called after internal validation."""

return

def execute(self, parameters, messages):

"""The source code of the tool."""

#Read input parameters

arcpy.AddMessage("Reading input parameters")

in_mapservice_name = "AdminAreasNOC_EN"#parameters[0].valueAsText

in_layer_names = "Emirate_District,AreaNames"#parameters[1].valueAsText

#You can read the following values from a config file

serverName = "192.168.9.30"

serverPort = "6080"

serverUName = "siteadmin"

serverPwd = "Pa$$w0rd"

response = []

datasetName = ""

try:

if not in_layer_names or not in_mapservice_name:

arcpy.AddMessage("Invalid input parameters")

else:

#Get Filepath of the map service

filePath = GetMapServiceFilePath(serverName,serverPort,serverUName,serverPwd,in_mapservice_name)

if filePath and os.path.exists(filePath.replace("msd","mxd")):

arcpy.AddMessage("MapDocument path is valid")

mxd = arcpy.mapping.MapDocument(filePath.replace("msd","mxd"))

if mxd:

arcpy.AddMessage("MapDocument has been loaded")

if "," in in_layer_names:

lst_layer_names = in_layer_names.split(",")

else:

lst_layer_names.append(in_layer_names)

for layer_name in lst_layer_names:

lyr = arcpy.mapping.ListLayers(mxd,layer_name)[0]

datasetName = ""

if lyr:

if lyr.supports("datasetName"):

datasetName = lyr.datasetName

del lyr

else:

arcpy.AddMessage("Couldn't load layer {0}".format(layer_name))

response.append({'layer': layer_name,'datasetName':datasetName})

del mxd

json.dumps(response)

#If an error occurs while running a tool

except arcpy.ExecuteError:

arcpy.AddMessage(arcpy.GetMessages(0))

arcpy.AddMessage(arcpy.GetMessages(1))

arcpy.AddMessage(arcpy.GetMessages(2))

#If any other error occurs

except Exception as e:

arcpy.AddMessage(str(e))

parameters[2].value = str(response)

def GetMapServiceFilePath(serverName,serverPort,uname,password,serviceName):

filePath = ""

try:

if serverName and serverPort and uname and password:

# Get a token

token = getToken(uname, password, serverName, serverPort)

# Get the root info

serverURL = "/arcgis/admin/services/"

# This request only needs the token and the response formatting parameter

params = urllib.urlencode({'token': token, 'f': 'json'})

headers = {"Content-type": "application/x-www-form-urlencoded", "Accept": "text/plain"}

# Connect to URL and post parameters

httpConn = httplib.HTTPConnection(serverName, serverPort)

httpConn.request("POST", serverURL, params, headers)

# Read response

response = httpConn.getresponse()

if (response.status != 200):

httpConn.close()

print "Could not read folder information."

return

else:

data = response.read()

# Check that data returned is not an error object

if not assertJsonSuccess(data):

arcpy.AddMessage("Error when reading server information. " + str(data))

return

else:

arcpy.AddMessage("Processed server information successfully. Now processing folders...")

# Deserialize response into Python object

dataObj = json.loads(data)

httpConn.close()

#Store the Folders in a list to loop on

folders = dataObj["folders"]

#Remove the System and Utilities folders

folders.remove("System")

#folders.remove("Utilities")

#Add an entry for the root folder

folders.append("")

#Loop on the found folders and discover the services and write the service information

for folder in folders:

# Determine if the loop is working on the root folder or not

if folder != "":

folder += "/"

# Build the URL for the current folder

folderURL = "/arcgis/admin/services/" + folder

params = urllib.urlencode({'token': token, 'f': 'json'})

headers = {"Content-type": "application/x-www-form-urlencoded", "Accept": "text/plain"}

# Connect to URL and post parameters

httpConn = httplib.HTTPConnection(serverName, serverPort)

httpConn.request("POST", folderURL, params, headers)

# Read response

response = httpConn.getresponse()

if (response.status != 200):

httpConn.close()

arcpy.AddMessage("Could not read folder information.")

return

else:

data = response.read()

# Check that data returned is not an error object

if not assertJsonSuccess(data):

arcpy.AddMessage("Error when reading folder information. " + str(data))

else:

arcpy.AddMessage("Processed folder information successfully. Now processing services...")

# Deserialize response into Python object

dataObj = json.loads(data)

httpConn.close()

# Loop through each service in the folder

for item in dataObj['services']:

if item["type"] == "MapServer" and str(item["serviceName"]).lower() == serviceName.lower():

# Build the Service URL

if folder:

sUrl = "/arcgis/admin/services/%s%s.%s" %(folder,item["serviceName"], item["type"])

else:

sUrl = "/arcgis/admin/services/%s.%s" %(item["serviceName"], item["type"])

# Submit the request to the server

httpConn.request("POST", sUrl, params, headers)

# Get the response

servResponse = httpConn.getresponse()

readData = servResponse.read()

jsonOBJ = json.loads(readData)

# get file path of the service

filePath = jsonOBJ["properties"]["filePath"]

return filePath

else:

# Close the connection to the current service

httpConn.close()

else:

arcpy.AddMessage("Invalid input parameters")

except Exception as e:

print str(e)

return filePath

def getToken(username, password, serverName, serverPort):

# Token URL is typically http://server[:port]/arcgis/admin/generateToken

tokenURL = "/arcgis/admin/generateToken"

params = urllib.urlencode({'username': username, 'password': password, 'client': 'requestip', 'f': 'json'})

headers = {"Content-type": "application/x-www-form-urlencoded", "Accept": "text/plain"}

# Connect to URL and post parameters

httpConn = httplib.HTTPConnection(serverName, serverPort)

httpConn.request("POST", tokenURL, params, headers)

# Read response

response = httpConn.getresponse()

if (response.status != 200):

httpConn.close()

print "Error while fetching tokens from admin URL. Please check the URL and try again."

return

else:

data = response.read()

httpConn.close()

# Check that data returned is not an error object

if not assertJsonSuccess(data):

return

# Extract the token from it

token = json.loads(data)

return token['token']

# A function that checks that the input JSON object

# is not an error object.

def assertJsonSuccess(data):

obj = json.loads(data)

if 'status' in obj and obj['status'] == "error":

print "Error: JSON object returns an error. " + str(obj)

return False

else:

return True

===============================================================================I hope that helps.

Regards,

Rami.

YousefQuran · ‎04-21-2015

Dear Rami,

Idk what is exactly the case, but I think you should publish a FeatureService in order to access to the data-source from REST. more details

RamiGhali2 · ‎04-21-2015

Dear Yusuf,

The case is that I want to get the dataset (featureclass) name of a specific featurelayer in a mapservice.

REST doesb't provide these info so, I've created geoprocessing service to do the job by accessing the MXD of the mapservice and get the dataset name of the requested layers.

Regards,

Rami.