Examples

1: Simple Task
2: Multi Host and Task

Komandan provides several examples that can be used to help you get started with Komandan.

1 - Simple Task

This example shows how to use the komando function to execute a simple command task on a remote server.

local host = {
    address = "10.20.30.41",
    user = "user1",
    private_key_file = "/path/to/private/key",
}

local task = {
    name = "Create a new directory",
    komandan.modules.cmd({
        cmd = "mkdir /tmp/new_dir"
    })
}

komandan.komando(host, task)

2 - Multi Host and Task

This example shows how to use multiple hosts and tasks in using Komandan.

hosts.lua:

return {
  {
    name = "server1",
    address = "10.20.30.41",
    user = "user2",
    tags = { "webserver" },
  },
  {
    name = "server2",
    address = "10.20.30.42",
    user = "user2",
    tags = { "dbserver" },
  },
  {
    address = "10.20.30.43",
    private_key_file = os.getenv("HOME") .. "/.ssh/id_ed25519",
    tags = { "dbserver" },
  },
}

main.lua:

local hosts = require("hosts")

komandan.set_defaults({
  user = "user1",
  private_key_file = os.getenv("HOME") .. "/.ssh/id_ed25519",
})

local tasks = {
  {
    name = "Create a directory",
    komandan.modules.cmd({
      cmd = "mkdir /tmp/newdir",
    }),
  },
  {
    name = "Delete a directory",
    komandan.modules.cmd({
      cmd = "rm -rf /tmp/newdir",
    }),
  },
}

local filtered_hosts = komandan.filter_hosts(hosts, "dbserver")

for _, task in pairs(tasks) do
  for _, host in pairs(filtered_hosts) do
    komandan.komando(host, task)
  end
end

This example will create a directory on all hosts that has name or tag dbserver and then delete the directory.