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 the Python requests package to be installed.

We have included a download link to third party distribution here which should be unzipped into your <IgnitionInstallationDirectory>/user-lib/pylib/site-packages folder. The requests package is distributed under the terms of the Apache 2.0 software license.

Running the script

In Ignition Designer, navigate to Tools > Script Console
Copy the script below and uncomment lines 21 and 24
Edit lines 21 and 24 for your deployment:
- Set the chariotUrl variable to the URL for your Chariot installation
- Update the userpassword key:value pair dictionary to assign a password to each MQTT Distributor user 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)
     
    #check for failures on httpCall
    if resp.status_code != 200:
        print "HTTPCall error code: " + str(resp.json())
        print "HTTPCall error detail: " + data
     
    return resp.json()
 
#Set URL for you Chariot installation
#chariotUrl = "http://localhost:8080"
 
#Create Chariot username:password dictionary for your MQTT Distributor users
#userpassword = {"admin":"password","test2":"password2","test3":"password3"}
 
#############################################################################
headers = {}

#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
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
users = system.cirruslink.distributor.readConfig("Users")
 
#Create new format Access Control Lists (ACLs)
for i in range(len(users)):
    subscribeList = ""
    publishList = ""   
    userName = users[i]["Username"]
    password = list(userpassword.values())[list(userpassword.keys()).index(userName)]
    acls = users[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] + "]}}]"
    http_response = httpCall("POST",url,headers,data)
 
 
#Read Chariot MQtt Users
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