nomad_mininet.py

#!/usr/bin/env python

import shutil

from mininet.cli import CLI
from mininet.net import Mininet
from mininet.topo import SingleSwitchTopo
from mininet.util import pmonitor

servers_count = 3
clients_count = 50

server_config = """
data_dir = "{data_dir}"
name     = "{name}"

server {{
  enabled          = true
  bootstrap_expect = {bootstrap_expect}

  server_join {{
    retry_join = [{servers}]
  }}
}}
"""

client_config = """
data_dir = "{data_dir}"
name     = "{name}"

client {{
  enabled = true
  servers = [{servers}]

  network_interface = "{network_interface}"
}}

plugin "raw_exec" {{
  config {{
    enabled = true
  }}
}}
"""

topo = SingleSwitchTopo(k=servers_count+clients_count)
net = Mininet(topo=topo)

servers = [net.hosts[i] for i in range(servers_count)]
clients = [net.hosts[i] for i in range(servers_count, clients_count)]

popens = {}

for s in servers:
  config_path = "/tmp/{}.hcl".format(s.name)
  data_dir_path = "/tmp/nomad-server-{}".format(s.name)

  config = server_config.format(
      name = s.name,
      data_dir = data_dir_path,
      bootstrap_expect = servers_count,
      servers = ",".join(["\"{}:4648\"".format(s.IP()) for s in servers])
  )


  f = open(config_path, "w")
  f.write(config)
  f.close()

  cmd = "/usr/local/bin/nomad agent -config {}".format(config_path)
  p = s.popen(cmd)
  popens[s.name] = p

for c in clients:
  config_path = "/tmp/{}.hcl".format(c.name)
  data_dir_path = "/tmp/nomad-client-{}".format(c.name)

  config = client_config.format(
      name = c.name,
      data_dir = data_dir_path,
      servers = ",".join(["\"{}:4647\"".format(s.IP()) for s in servers]),
      network_interface = "{}-eth0".format(c.name)
  )

  f = open(config_path, "w")
  f.write(config)
  f.close()

  cmd = "/usr/local/bin/nomad agent -config {}".format(config_path)
  p = c.popen(cmd)
  popens[c.name] = p

net.start()
CLI(net)

# Cleanup
for p in popens.values():
  p.terminate()
for s in servers:
  shutil.rmtree("/tmp/nomad-server-{}".format(s.name))
for c in clients:
  shutil.rmtree("/tmp/nomad-client-{}".format(c.name))

net.stop()