# File

{% dynamic setvar source_file "src/main/java/com/google/devtools/build/lib/starlarkbuildapi/FileApi.java" %} {% dynamic setvar version "8.4.0" %} {% dynamic setvar original_path "/rules/lib/builtins/File" %} {% include "_buttons.html" %} This object is created during the analysis phase to represent a file or directory that will be read or written during the execution phase. It is not an open file handle, and cannot be used to directly read or write file contents. Rather, you use it to construct the action graph in a rule implementation function by passing it to action-creating functions. See the Rules page for more information.

When a `File` is passed to an `Args` object without using a `map_each` function, it is converted to a string by taking the value of its `path` field.

## Members

- basename
- dirname
- extension
- is_directory
- is_source
- is_symlink
- owner
- path
- root
- short_path
- tree_relative_path

## basename

    string File.basename

The base name of this file. This is the name of the file inside the directory.

## dirname

    string File.dirname

The name of the directory containing this file. It's taken from path and is always relative to the execution directory.

## extension

    string File.extension

The file extension of this file, following (not including) the rightmost period. Empty string if the file's basename includes no periods.

## is_directory

    bool File.is_directory

Returns true if this is a directory. This reflects the type the file was declared as (i.e. ctx.actions.declare_directory), not its type on the filesystem, which might differ.

## is_source

    bool File.is_source

Returns true if this is a source file, i.e. it is not generated.

## is_symlink

    bool File.is_symlink

Returns true if this was declared as a symlink. This reflects the type the file was declared as (i.e. ctx.actions.declare_symlink), not its type on the filesystem, which might differ.

## owner

    Label File.owner

A label of a target that produces this File. May return `None`.

## path

    string File.path

The execution path of this file, relative to the workspace's execution directory. It consists of two parts, an optional first part called the root (see also the root module), and the second part which is the `short_path`. The root may be empty, which it usually is for non-generated files. For generated files it usually contains a configuration-specific path fragment that encodes things like the target CPU architecture that was used while building said file. Use the `short_path` for the path under which the file is mapped if it's in the runfiles of a binary.

## root

    root File.root

The root beneath which this file resides.

## short_path

    string File.short_path

The path of this file relative to its root. This excludes the aforementioned root, i.e. configuration-specific fragments of the path. This is also the path under which the file is mapped if it's in the runfiles of a binary.

## tree_relative_path

    string File.tree_relative_path

The path of this file relative to the root of the ancestor's tree, if the ancestor's is_directory field is true. `tree_relative_path` is only available for expanded files of a directory in an action command, i.e. Args.add_all(). For other types of files, it is an error to access this field.