helm/docs/chart_template_guide/builtin_objects.md

# Built-in Objects

Objects are passed into a template from the template engine. And your code can pass objects around (we'll see examples when we look at the `with` and `range` statements). There are even a few ways to create new objects within your templates, like with the `tuple` function we'll see later.

Objects can be simple, and have just one value. Or they can contain other objects or functions. For example. the `Release` object contains several objects (like `Release.Name`) and the `Files` object has a few functions.

In the previous section, we use `{{.Release.Name}}` to insert the name of a release into a template. `Release` is one of four top-level objects that you can access in your templates.

- `Release`: This object describes the release itself. It has several objects inside of it:
	- `Release.Name`: The release name
	- `Release.Time`: The time of the release
	- `Release.Namespace`: The namespace to be released into (if the manifest doesn't override)
	- `Release.Service`: The name of the releasing service (always `Tiller`).
- `Values`: Values passed into the template from the `values.yaml` file and from user-supplied files. By default, `Values` is empty.
- `Chart`: The contents of the `Chart.yaml` file. Any data in `Chart.yaml` will be accessible here. For example `{{.Chart.Name}}-{{.Chart.Version}}` will print out the `mychart-0.1.0`.
  - The available fields are listed in the [Charts Guide](charts.md)
- `Files`: This provides access to all non-special files in a chart. While you cannot use it to access templates, you can use it to access other files in the chart. See the section _Accessing Files_ for more.
  - `Files.Get` is a function for getting a file by name (`.Files.Get config.ini`)
  - `Files.GetBytes` is a function for getting the contents of a file as an array of bytes instead of as a string. This is useful for things like images.

The values are available to any top-level template. As we will see later, this does not necessarily mean that they will be available _everywhere_.

The built-in values always begin with a capital letter. This is in keeping with Go's naming convention. When you create your own names, you are free to use a convention that suits your team. Some teams, like the [Kubernetes Charts](https://github.com/kubernetes/charts) team, choose to use only initial lower case letters in order to distinguish local names from those built-in. In this guide, we follow that convention.