Migrating MQTT Distributor Users to Chariot MQTT Credentials

The sample Python script below will allow you to migrate credentials from MQTT Distributor to Chariot at scale using the MQTT Distributor API and the Chariot REST API.

The script is designed to run from the Script Console in the Ignition instance where MQTT Distributor is installed and will:

read the user configuration from the MQTT Distributor
transform the users to the required Chariot REST API format
add the users to the Chariot MQTT Credentials store
read and output the Chariot MQTT Credentials

Prerequisites

The script requires a number of Python packages to be installed. We have included a download link to third party distributions for these prerequisite libraries which should be extracted into your <IgnitionInstallationDirectory>/user-lib/pylib/site-packages folder if not already present.

The requests package is distributed under the terms of the Apache 2.0 software license

The urllib3 package is distributed under the terms of the MIT license software license

The chardet package is distributed under the terms of the LGPL v2.1 software license

The certifi package is distributed under the terms of the Mozilla Public License 2.0

The idna package is distributed under the terms of the bsd-3-clause license

Running the script

In Ignition Designer, navigate to Tools > Script Console
Copy the script below
Set the configuration variables for your installation:
- Set the chariotUrl variable to the URL for your Chariot installation
- Set the migrateDistributorUsers dictionary to assign a password to each MQTT Distributor user to be migrated as user passwords are not returned via the MQTT Distributor API
Select the Execute button

import requests
import base64
  
#HTTP call method
def httpCall(method,url,headers,data):
    if method == "POST":
        resp = requests.post(url, headers=headers, data=data)
    if method == "GET":
        resp = requests.get(url, headers=headers, data=data)
    if method == "PUT":
        resp = requests.put(url, headers=headers, data=data)
    
    print "HTTPCall response: " + str(resp.status_code)
    #check for failures on httpCall
    if resp.status_code != 200:
        print "HTTPCall error detail: " + str(resp.json())
    
    print	  
    return resp.json()
  
#############################################################################
# Configure Chariot URL and MQTT Distributor users to migrate
#############################################################################

#Set URL for your Chariot installation
chariotUrl = "http://localhost:8080"
  
#Create dictionary for all MQTT Distributor users to be migrated with key/value pairs of UserName/Password
migrateDistributorUsers = {
 	"admin":"password",
 	"user1":"password1",
 	"user2":"password2"
 	}
  
#############################################################################
headers = {}
 
#Accept Chariot EULA
print "Accept Chariot EULA"
url = chariotUrl + "/eula"
headers["accept"] = "application/json;api-version=1.0"
headers["content-type"] = "application/json"
data = "{\"isAccepted\": true}"
http_response = httpCall("POST",url,headers,data)
  
#Chariot login using admin user to get bearer token valid for 90 minutes
print "Chariot login and get bearer token"
url = chariotUrl + "/login"
headers["accept"] = "application/json;api-version=1.0"
headers["Authorization"] = "Basic " + base64.b64encode("admin:password")
data = {}
http_response = httpCall("POST",url,headers,data)
accessToken = http_response["access_token"]
  
#Read Distributor users
print "Read MQTT Distributor users"
print
distributorUsers = system.cirruslink.distributor.readConfig("Users")
  
#Create new format Access Control Lists (ACLs)
for i in range(len(distributorUsers)):
    subscribeList = ""
    publishList = ""  
    userName = distributorUsers[i]["Username"]
    #check to see if MQTT Distributor user is included in migration list
    if userName in migrateDistributorUsers.keys():
    	print "Migrating MQTT Distributor User: " + userName   
    	password = list(migrateDistributorUsers.values())[list(migrateDistributorUsers.keys()).index(userName)]
    	acls = distributorUsers[i]["ACLs"]
    	acl_list = acls.split(",")
    	for i in range(len(acl_list)):
    	    #check for leading spaces
    	    if acl_list[i][:1] == " ":
    	        acl_list[i] = acl_list[i][1:len(acl_list[i])]
    	    #check for R subscriptions
    	    if acl_list[i][:2] == "R ":
    	        subscription = acl_list[i][2:len(acl_list[i])]
    	        subscription = "\"" + subscription + "\""
    	        subscribeList = subscribeList + subscription + ","
    	    #check for W subscriptions
    	    if acl_list[i][:2] == "W ":
    	        publish = acl_list[i][2:len(acl_list[i])]
    	        publish = "\"" + publish + "\""
    	        publishList = publishList + publish + ","
    	    #check for RW subscription
    	    if acl_list[i][:2] == "RW":
    	        subscription = acl_list[i][3:len(acl_list[i])]
    	        subscription = "\"" + subscription + "\""
    	        subscribeList = subscribeList + subscription + ","
    	        publish = acl_list[i][3:len(acl_list[i])]
    	        publish = "\"" + publish + "\""
    	        publishList = publishList + publish + ","
                  
    	#create Chariot user
    	url = chariotUrl + "/mqttusers"
    	headers["accept"] = "application/json;api-version=1.0"
    	headers["content-type"] = "application/json"
    	headers["Authorization"] = "Bearer " + accessToken
    	data = "[{\"username\":\"" + userName + "\"," + "\"password\":\"" + password + "\"," + "\"acl\":{\"publishTopics\":[" + publishList[:-1] +"],\"subscribeTopics\":[" + subscribeList[:-1] + "]}}]"
    	print "Creating MQTT Credentials: " + str(data)
    	http_response = httpCall("POST",url,headers,data)
    
    else:
      	print "Not migrating MQTT Distributor User: " + userName
		print  
  
#Read Chariot MQtt Users
print "Reading Chariot MQTT Credentials"
url = chariotUrl + "/mqttusers"
headers["accept"] = "application/json;api-version=1.0"
headers["Authorization"] = "Bearer " + accessToken
data = {}
chariotMqttUsers = httpCall("GET",url,headers,data)
print "Chariot MQTT Credentials: " + str(chariotMqttUsers)

Contents

Cirrus Link Resources

Prerequisites

Running the script