Generate Bosh pcap commands from app guid

pcap.py

import json, os, shutil, subprocess, sys

def main(app_guids):
  check_binary("cf")
  check_binary("bosh")
  # Checking cf logged in
  target = subprocess.run(['cf', 'target'], stdout=subprocess.PIPE, stderr=subprocess.PIPE)
  if target.returncode != 0:
    print(f"cf commands fail with {target.stderr}")
    sys.exit(1)

  
  spec_apps = []
  for app_guid in app_guids.split(','):
    app_json = subprocess.run(['cf', 'curl', f'/v3/apps/{app_guid}'], stdout=subprocess.PIPE, stderr=subprocess.PIPE)
    if b"CF-ResourceNotFound" in app_json.stdout:
      print(f"App guid {app_guid} does not exist")
      sys.exit(1)
    app = json.loads(app_json.stdout)
    spec_apps.append({'guid': app_guid, 'name': app['name'], 'guid_slice': app_guid.split("-")[0]})
    continue
  
  pcap(spec_apps)

def pcap(spec_apps):
  app_commands = []
  app_ips = []
  diego_instance_names = get_diego_instance_names()
  cf_dep_name = get_cf_dep_name()

  for spec_app in spec_apps:
    print(f"Collecting details for {spec_app['name']}:{spec_app['guid']}")
    processes = get_ips(spec_app['guid'])

    for resources in processes['resources']:
      app_ips.append(resources['instance_internal_ip'])
      app_commands.append(get_instance_command(resources['host'], resources['instance_internal_ip'],
                    diego_instance_names, cf_dep_name, spec_app))
    
    print("Commands below:\n\n")
    router_hosts = ' or host '.join(app_ips)
    print(f"bosh -d {cf_dep_name} pcap router -o router.pcap -f 'host {router_hosts}' -s 128")
    for app_command in app_commands:
      print(app_command)

def get_cf_dep_name():
  deps = subprocess.run(['bosh', 'deps', "--json"], stdout=subprocess.PIPE, env=os.environ.copy())
  for deployment in json.loads(deps.stdout)['Tables']:
    for dep in deployment['Rows']:
      if 'cf-' in dep['name']:
        return dep['name']
  return "parp"

def get_diego_instance_names():
  vms_out = subprocess.run(['bosh', 'vms', "--json"], stdout=subprocess.PIPE, env=os.environ.copy())
  if vms_out.returncode != 0:
    print(f"bosh commands fail with {vms_out.stdout}")
    sys.exit(1)
  ip_to_instance_name = {}
  vms = json.loads(vms_out.stdout)
  for deployment in vms['Tables']:
    for vm in deployment['Rows']:
      ip_to_instance_name.update({vm['ips']: vm['instance']})
  return ip_to_instance_name

def get_ips(app_guid):
  result = subprocess.run(['cf', 'curl', f"/v3/processes/{app_guid}/stats"], stdout=subprocess.PIPE)
  return json.loads(result.stdout)

def get_instance_command(host_ip, container_ip, diego_instance_names, cf_dep_name, spec_app):
  print(f"Collecting interface for instance {container_ip}")
  deigo_cell = diego_instance_names[host_ip]

  cmd = ['bosh', '-d', cf_dep_name, 'ssh', deigo_cell, '-c', 
         f'/var/vcap/packages/cfdot/bin/cfdot actual-lrps --bbsURL https://bbs.service.cf.internal:8889 --caCertFile /var/vcap/jobs/cfdot/config/certs/cfdot/ca.crt --clientCertFile /var/vcap/jobs/cfdot/config/certs/cfdot/client.crt --clientKeyFile /var/vcap/jobs/cfdot/config/certs/cfdot/client.key |grep {container_ip}', 
         '--json']
  bosh_out = subprocess.run(cmd, stdout=subprocess.PIPE, env=os.environ.copy())
  command_lines = json.loads(bosh_out.stdout)['Blocks']

  for line in command_lines:
    if "process_guid" in line:
      process_details = json.loads(line)
      port_name = process_details['instance_guid'][:15]
      return_cmd = f"bosh -d {cf_dep_name} pcap {deigo_cell} -o app_{spec_app['name']}_{spec_app['guid_slice']}_{container_ip}.pcap -i {port_name} -s 128"
      return return_cmd

def check_binary(binary_name):
  if shutil.which(binary_name) == None:
    print(f"{binary_name} is not available via the PATH")
    sys.exit(1)


if __name__ == '__main__':
  if len(sys.argv) < 2:
    print("you must pass in a comma separated string of app IPs")
    print("E.g: python pcap.py 326f2a4f-3a00-4d82-945a-bd2efeeb4371,326f2a4f-3a00-4d82-945a-bd2efeeb4372")
    sys.exit(1)
  app_guids = sys.argv[1]
  main(app_guids)