The following items are new for Chef Infra Client 12.3 and/or are changes from previous versions. The short version:

- **Socketless local mode with chef-zero** Port binding and HTTP requests on localhost may be disabled in favor of socketless mode.
- **Minimal Ohai plugins** Run only the plugins required for name resolution and resource/provider detection.
- **Dynamic resource and provider resolution** Four helper methods may be used in a library file to get resource and/or provider mapping details, and then set them per-resource or provider.
- **New clear_sources attribute for the chef_gem and gem_package resources** Set to `true` to download a gem from the path specified by the `source` property (and not from RubyGems).

## Socketless Local Mode

Chef Infra Client may disable port binding and HTTP requests on localhost by making a socketless request to chef-zero. This may be done from the command line or with a configuration setting.

Use the following command-line option:

`--[no-]listen`

:   Run chef-zero in socketless mode. Use `--no-listen` to disable port
    binding and HTTP requests on localhost.

Or add the following setting to the client.rb file:

<table>
<colgroup>
<col style="width: 40%" />
<col style="width: 60%" />
</colgroup>
<thead>
<tr class="header">
<th>Setting</th>
<th>Description</th>
</tr>
</thead>
<tbody>
<tr>
<td><code>listen</code></td>
<td>Run chef-zero in socketless mode. Set to <code>false</code> to disable port binding and HTTP requests on localhost.</td>
</tr>
</tbody>
</table>

## Minimal Ohai

The following option may be used with chef-client, chef-solo, and chef-apply to speed up testing intervals:

`--minimal-ohai`

:   Run the Ohai plugins for name detection and resource/provider
    selection and no other Ohai plugins. Set to `true` during
    integration testing to speed up test cycles.

This setting may be configured using the `minimal_ohai` setting in the client.rb file.

## Dynamic Resolution

Resources and providers are resolved dynamically and can handle multiple
`provides` lines for a specific platform. When multiple `provides` lines
exist, such as `Homebrew` and `MacPorts` packages for the macOS
platform, then one is selected based on resource priority mapping
performed by Chef Infra Client during Chef Infra Client run.

Use the following helpers in a library file to get and/or set resource
and/or provider priority mapping before any recipes are compiled:

`Chef.get_provider_priority_array(resource_name)`

:   Get the priority mapping for a provider.

`Chef.get_resource_priority_array(resource_name)`

:   Get the priority mapping for a resource.

`Chef.set_provider_priority_array(resource_name, Array<Class>, *filter)`

:   Set the priority mapping for a provider.

`Chef.set_resource_priority_array(resource_name, Array<Class>, *filter)`

:   Set the priority mapping for a resource.

For example:

```ruby
Chef.set_resource_priority_array(:package, [ Chef::Resource::MacportsPackage ], os: 'darwin')
```