fgs_update_pids.py

import requests
import time

fgs_url = 'http://islandora:8080/fedoragsearch/rest'

user = 'fedoraAdmin'
password = 'XXXXX'

fgs_session = requests.Session()
fgs_session.auth = (user, password)

# UPDATED BCRW PIDS FROM 0 to 1522 INCLUSIVE
pid_start = 0
pid_end = 1522
pid_current = 0
while (pid_current <= pid_end):
    print('Updating pid: ' + str(pid_current))
    time.sleep(.5)    
    
    data = {
        'operation': 'updateIndex',
        'action': 'fromPid',
        'value': 'bcrw:' + str(pid_current)
        }

    response = fgs_session.post(fgs_url, data=data)
    print(response.status_code)

    pid_current += 1

Ben - the response page has more details on failure and/or success ~ parse it maybe?