import requests
from requests.auth import HTTPBasicAuth
import json
import csv

# Jira Cloud URL - update this value to your cloud url
jira_url = "https://Your-Instance.atlassian.net/"

# API endpoint for adding users to a group
api_endpoint = f"{jira_url}/rest/api/3/group/user"

# Authentication credentials - update the email and api_token for your user and token combination
email = "Your-Email@mail.com"
api_token = "Your-Token"

# Read the CSV file with user and group IDs
csv_file_path = "users_and_groups.csv"

auth = HTTPBasicAuth(email, api_token)

headers = {
    "Accept": "application/json",
    "Content-Type": "application/json",
}

# Process the CSV file
with open(csv_file_path, mode="r") as csv_file:
    csv_reader = csv.DictReader(csv_file)
    for row in csv_reader:
        user_id = row["userid"]  # Change to match your CSV column names
        group_id = row["groupid"]  # Change to match your CSV column names

        # Construct the JSON payload
        payload = json.dumps({"accountId": user_id})

        # Set the query parameters for the group ID
        query = {"groupId": group_id}

        # Make the API request to add the user to the group
        response = requests.post(
            api_endpoint,
            data=payload,
            headers=headers,
            params=query,
            auth=auth,
        )

        if response.status_code == 201:
            print(f"Added user with ID '{user_id}' to group with ID '{group_id}'.")
        else:
            print(
                f"Failed to add user with ID '{user_id}' to group. Status Code: {response.status_code}"
            )

$ curl -s -H "Authorization: Bearer NzY5OTM5NTM4MTI4OpbOYE6v/WgmSSWaCJNUJiz/JZtH" -X POST -H "Content-Type: application/json"  --data '{"name": "admin"}' "http://localhost:49121/j9121/rest/api/latest/group/user?groupname=Group-A"
{"name":"Group-A","self":"http://localhost:49121/j9121/rest/api/2/group?groupname=Group-A","users":{"size":3,"items":[],"max-results":50,"start-index":0,"end-index":0},"expand":"users"

import requests
from requests.auth import HTTPBasicAuth
from urllib.parse import urlencode, quote_plus
import json
import csv

#
# https://confluence.atlassian.com/jirakb/bulk-add-users-to-groups-using-python-and-api-1299910891.html
# 
# THIS SCRIPT WORKS FOR JIRA DATA CENTER ONLY
#

# Jira URL - update this value to your Jira url
jira_url = "<Jira URL>"
# Example: jira_url = "http://localhost:49121/j9121"

# API endpoint for adding users to a group
api_endpoint = f"{jira_url}/rest/api/latest/group/user"

# Authentication credentials - using PAT (bearer token)
bearer_token = "Your-Token"
# Example bearer_token = "NzY5OTM5NTM4MTI4OpbOYE6v/abcdefghijklmnopqrstuvwxyz"

# Read the CSV file with user and group IDs
csv_file_path = "users_and_groups.csv"

# using bearer token in header
headers = {
    "Accept": "application/json",
    "Content-Type": "application/json",
    "Authorization": f"Bearer {bearer_token}"
}
# Process the CSV file
with open(csv_file_path, mode="r") as csv_file:
    csv_reader = csv.DictReader(csv_file)
    for row in csv_reader:
        user_name = row["username"]  # Change to match your CSV column names
        group_name = row["groupname"]  # Change to match your CSV column names

        # Construct the JSON payload for username to be added to the group
        payload = json.dumps({"name": user_name})

        # Set the query parameters for the group name
        query = {"groupname": group_name}

        # Make the API request to add the user to the group
		# Note: use urlencode for query parameter containing special characters
        response = requests.post(
            api_endpoint,
            data=payload,
            headers=headers,
            params=urlencode(query)
        )

        if response.status_code == 201:
            print(f"Added user '{user_name}' to group '{group_name}'.")
        else:
            print(
                f"Failed to add user '{user_name}' to group '{group_name}'. Status Code: {response.status_code}."
            )

python3 <python script file path>

% python3 bulk-add-user-to-group.py 

Added user 'admin' to group 'Group-A'.
Added user 'frank' to group 'Group-A'.
Added user 'chimp2' to group 'Group-A'.