A feature is available in Chocolatey CLI v1.2.0, which allows you to extend a package's automation script(s) with additional PowerShell scripts, called hooks.

Overview

Hooks allow you to run code before a package automation script like a chocolateyInstall.ps1 runs, or after. They even work when automation scripts are not included in the package. Each script can selectively target a single package ID, or run for all packages. Then they can be distributed using .hook packages.

Creating Hook Scripts

Hook scripts are PowerShell .ps1 files, and are run in the same environment as package automation scripts run, so they have access to all the same environment variables and helpers.

The conditions for when a hook is run is based on the filename of the hook. The filename format is <pre|post>-<install|beforemodify|uninstall>-<packageID|all>.ps1. The first section is for the timing of when the hook script runs. Filenames that start with pre run before the package automation script (e.g. the chocolateyInstall.ps1), while filenames that start with post are run afterwards. The second section of the filename determines which package automation script the hook is run before or after. The third section of the filename is either a string of the package ID for which the hook should be run, or the keyword all to specify that the hook should be run for all package IDs.

If a package does not contain a chocolateyInstall.ps1, but a pre-install-all.ps1 hook is installed, then that hook will still run at the same point in the package installation as the chocolateyInstall.ps1 would have been run if the package had included it.

Creating Hook Packages

Hooks can be installed just like extensions, via a specific package type, namely .hook. The name of the installed hook folder is the package id, minus the .hook.

How to create a Hook package:

1. Create a package with a .hook suffix like choco new name.hook
2. Delete the created files and folders except for the .nuspec
3. Create a hook folder in the root of the package (next to the .nuspec).
4. Put your hook PowerShell script files inside the hook folder.
5. Pack and install your new Hook package.

Global Hooks

These files are run either before (pre) or after (post) the normal Chocolatey install/upgrade/uninstall operation, for all Chocolatey packages.

Once a global hook is installed (either manually or via hook package), any subsequent Chocolatey operations (say for example the installation of another package), will make use of the newly installed (or available), hook scripts.

Package Specific Hooks

You can also create a package-specific hook by following the naming convention <pre|post>-<install|beforemodify|uninstall>-<packageID>.ps1 where <packageID> is the id of the Chocolatey package you would wish to execute hooks against.

The hooks will behave in the same way as global hooks, running either before (pre) or after (post) the normal Chocolatey install/upgrade/uninstall operation for only a Chocolatey package whose id matches the id in the hook script name.

Skipping Hooks

Chocolatey provides away for skipping the running of hooks for a particular package. If you would like to skip hooks for the installation of a particular package, simply add the --skip-hooks option to the list of parameters you pass to the command.

Recommendations

Still under development

Hook scripts and packages are still new, so guidelines and best practices are still being determined. Follow along at the Chocolatey Community Hooks Repository for the latest information.

Avoid taking dependencies on regular packages

It is best to avoid having a .hook package taking a dependency on regular packages. This is so the included hooks from the package can be installed before other packages get initially installed. For example, if there is a pre-install-git.ps1 hook and the .hook package it is included in takes a dependency on git, then the chocolateyInstall.ps1 from the git package would have already run before the hook is installed, which is counterproductive.

Do take dependencies on extension packages

If any hook script in a .hook package require helpers from an .extension package, then make sure that the .hook package takes a dependency on that .extension package.

Don't take dependencies on hook packages

Don't add a hook package as a dependency for your regular package. Hook scripts are intended to be added only by the user of Chocolatey CLI. If your package requires functionality similar to that which would normally be provided via a hook script package, then it should be added directly to the standard automation scripts for the package. Adding a hook package as a dependency to your regular package will cause the package to fail validation on the Chocolatey Community Repository.

Don't add hook scripts to regular packages

Don't add hook scripts to your regular Chocolatey package. If your package requires functionality similar to that which would normally be provided via a hook script package, then it should be added directly to the standard automation scripts for the package. Adding a hook script to your regular package will cause the package to fail validation on the Chocolatey Community Repository.