NodeActivator

A module to activate VM nodes.

This module provides functionality to turn a non-distributed Erlang node into a distributed node. It handles the entire process of node activation, including:

Ensuring the EPMD (Erlang Port Mapper Daemon) is running
Generating unique node names
Starting the distributed node
Providing proper error handling and logging

Features

Automatic EPMD activation
Unique node name generation with customizable prefixes
Idempotent operation (safe to call multiple times)
Comprehensive error handling
Detailed logging of node operations

Usage

The main function run/1 takes a prefix string and returns either:

{:ok, node()} - The node was successfully started or was already running
{:error, reason} - An error occurred during node activation

Dependencies

epmd_up - For EPMD management
get_host - For hostname resolution

Examples

# Start a new distributed node with prefix "myapp"
{:ok, node_name} = NodeActivator.run("myapp")
# => {:ok, :"myapp_abc123@hostname"}

# Safe to call multiple times
{:ok, same_node} = NodeActivator.run("myapp")
# => {:ok, :"myapp_abc123@hostname"}

Installation

The package can be installed by adding node_activator to your list of dependencies in mix.exs:

def deps do
  [
    {:node_activator, "~> 1.1"}
  ]
end

Documentation can be generated with ExDoc and published on HexDocs. Once published, the docs can be found at https://hexdocs.pm/node_activator.

Tested Platforms

Ubuntu 22.04 / Elixir 1.19 / OTP 28
Ubuntu 22.04 / Elixir 1.18 / OTP 28
Ubuntu 22.04 / Elixir 1.18 / OTP 27
Ubuntu 22.04 / Elixir 1.17 / OTP 27
Ubuntu 22.04 / Elixir 1.16 / OTP 26
Ubuntu 22.04 / Elixir 1.15 / OTP 25
Windows 2022 / Elixir 1.19 / OTP 28
Windows 2022 / Elixir 1.18 / OTP 28
macOS Sonoma on Apple Silicon / Elixir 1.18 / OTP 28

License

Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.