Redirecting Request by Country or Latency

redirect-based-on-latency.py

# Need to install DNS package
import dns.resolver
def lambda_handler(event, context):
 request = event['Records'][0]['cf']['request']
 res = dns.resolver.query("latency-cross-region.example.com", "txt")
 buff = res[0].to_text().replace('"', '').split(";")
 bucket_name = buff[0]
 region = buff[1]
 domainName = f"{bucket_name}.s3.{region}.amazonaws.com"
 request['origin']['s3']['domainName'] = domainName
 request['origin']['s3']['path'] = ''
 request['origin']['s3']['region'] = region
 request['headers']['host'] = [{'key':'Host', 'value': domainName}]
 return request