Trooper

Trooper is an automation and remote execution library in Erlang. It connects to remote machines via SSH, performs commands (one-off, long-polling, interactive shells with PTY allocation), transfers files via SFTP/SCP, and supports multi-hop SSH proxy tunneling.

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Features

• SSH Execution (trooper_ssh):
  • Connect with passwords, RSA/DSA/ECDSA private keys (file paths or binary terms), or ssh-agent.
  • Run one-time commands (exec/2,3).
  • Run streaming and interactive commands via exec_long_polling/2,3 with optional PTY allocation (ptty_allow).
  • Channel reuse with start_chan/1 and stop_chan/1.
  • Scoped connections via transaction/2.
• SFTP File Transfers (trooper_scp):
  • Read and write remote files (read_file/2, write_file/3).
  • Directory management (list_dir/2, make_dir/2, del_dir/2).
  • File management (delete/2, rename/3, make_symlink/3).
  • Streaming file handles (open/3, read/2, write/2, close/1).
• SSH Multi-hop Proxy Chains (trooper_proxy):
  • Tunnel connections through one or more intermediate bastion/proxy hosts.
  • Transparent port bridging via TCP forwards.

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Installation

Add trooper to your rebar.config dependencies:

{deps, [
    {trooper, "~> 1.2"}
]}.

Or for Elixir projects in mix.exs:

def deps do
  [
    {:trooper, "~> 1.2"}
  ]
end

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Quick Examples

One-shot Command Execution

{ok, KeyData} = file:read_file("/path/to/id_rsa"),
Opts = [
    {host, "remote.server.com"},
    {user, "deploy"},
    {id_rsa, KeyData}
],
{ok, Trooper} = trooper_ssh:start(Opts),
{ok, 0, Output} = trooper_ssh:exec(Trooper, "uname -a"),
ok = trooper_ssh:stop(Trooper).

Interactive Command with Long Polling & PTY

Opts = [
    {host, "remote.server.com"},
    {user, "deploy"},
    {id_rsa, KeyData},
    {ptty_allow, true}
],
{ok, Trooper} = trooper_ssh:start(Opts),
WorkerPid = trooper_ssh:exec_long_polling(Trooper, "bash"),
WorkerPid ! {send, "echo 'Hello Trooper'\n"},
%% Incoming responses are sent as messages to the calling process:
%% {continue, <<"Hello Trooper\n">>}
%% {exit_status, 0}
%% closed
ok = trooper_ssh:stop(Trooper).

SFTP Remote File Operations

{ok, Trooper} = trooper_ssh:start(Opts),
ok = trooper_scp:write_file(Trooper, "/tmp/config.json", <<"{\"key\":\"value\"}">>),
{ok, Content} = trooper_scp:read_file(Trooper, "/tmp/config.json"),
{ok, Files} = trooper_scp:list_dir(Trooper, "/tmp"),
ok = trooper_scp:delete(Trooper, "/tmp/config.json"),
ok = trooper_ssh:stop(Trooper).

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Documentation

Full documentation is available on HexDocs.

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License

This project is licensed under the terms of the MIT License.

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Support & Donations

If you find this project useful, you can support its development: