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docs	Packer Plugins - Extend Packer	Packer Plugins allow new functionality to be added to Packer without modifying the core source code. Packer plugins are able to add new commands, builders, provisioners, hooks, and more. In fact, much of Packer itself is implemented by writing plugins that are simply distributed with Packer. For example, all the commands, builders, provisioners, and more that ship with Packer are implemented as Plugins that are simply hardcoded to load with Packer.

Packer Plugins

Packer Plugins allow new functionality to be added to Packer without modifying the core source code. Packer plugins are able to add new commands, builders, provisioners, hooks, and more. In fact, much of Packer itself is implemented by writing plugins that are simply distributed with Packer. For example, all the commands, builders, provisioners, and more that ship with Packer are implemented as Plugins that are simply hardcoded to load with Packer.

This page will cover how to install and use plugins. If you're interested in developing plugins, the documentation for that is available the developing plugins page.

Because Packer is so young, there is no official listing of available Packer plugins. Plugins are best found via Google. Typically, searching "packer plugin x" will find what you're looking for if it exists. As Packer gets older, an official plugin directory is planned.

How Plugins Work

Packer plugins are completely separate, standalone applications that the core of Packer starts and communicates with.

These plugin applications aren't meant to be run manually. Instead, Packer core executes these plugin applications in a certain way and communicates with them. For example, the VMware builder is actually a standalone binary named packer-builder-vmware. The next time you run a Packer build, look at your process list and you should see a handful of packer- prefixed applications running.

Installing Plugins

The easiest way to install a plugin is to name it correctly, then place it in the proper directory. To name a plugin correctly, make sure the binary is named packer-TYPE-NAME. For example, packer-builder-amazon-ebs for a "builder" type plugin named "amazon-ebs". Valid types for plugins are down this page more.

Once the plugin is named properly, Packer automatically discovers plugins in the following directories in the given order. If a conflicting plugin is found later, it will take precedence over one found earlier.

1. The directory where packer is, or the executable directory.

2. ~/.packer.d/plugins on Unix systems or %APPDATA%/packer.d/plugins on Windows.

3. The current working directory.

The valid types for plugins are:

• builder - Plugins responsible for building images for a specific platform.

• command - A CLI sub-command for packer.

• post-processor - A post-processor responsible for taking an artifact from a builder and turning it into something else.

• provisioner - A provisioner to install software on images created by a builder.