directories 2.0.2

A tiny mid-level library that provides platform-specific standard locations of directories for config, cache and other data on Linux, Windows and macOS by leveraging the mechanisms defined by the XDG base/user directory specifications on Linux, the Known Folder API on Windows, and the Standard Directory guidelines on macOS.

crates.io API documentation actively developed TravisCI status AppVeyor status License: MIT/Apache-2.0

directories

Introduction

  • a tiny mid-level library with a minimal API
  • that provides the platform-specific, user-accessible locations
  • for retrieving and storing configuration, cache and other data
  • on Linux, Redox, Windows (≥ Vista), macOS and other platforms.

The library provides the location of these directories by leveraging the mechanisms defined by

Platforms

This library is written in Rust, and supports Linux, Redox, macOS and Windows. Other platforms are also supported; they use the Linux conventions.

dirs, the low-level sister library, is available at dirs-rs.

A version of this library running on the JVM is provided by directories-jvm.

Usage

Dependency

Add the library as a dependency to your project by inserting

directories = "2.0"

into the [dependencies] section of your Cargo.toml file.

Example

Library run by user Alice:

extern crate directories;
use directories::{BaseDirs, UserDirs, ProjectDirs};

if let Some(proj_dirs) = ProjectDirs::from("com", "Foo Corp",  "Bar App") {
    proj_dirs.config_dir();
    // Lin: /home/alice/.config/barapp
    // Win: C:\Users\Alice\AppData\Roaming\Foo Corp\Bar App\config
    // Mac: /Users/Alice/Library/Preferences/com.Foo-Corp.Bar-App
}

if let Some(base_dirs) = BaseDirs::new() {
    base_dirs.executable_dir();
    // Lin: Some(/home/alice/.local/bin)
    // Win: None
    // Mac: None
}

if let Some(user_dirs) = UserDirs::new() {
    user_dirs.audio_dir();
    // Lin: /home/alice/Music
    // Win: C:\Users\Alice\Music
    // Mac: /Users/Alice/Music
}

Design Goals

  • The directories library is designed to provide an accurate snapshot of the system's state at the point of invocation of BaseDirs::new, UserDirs::new or ProjectDirs::from. Subsequent changes to the state of the system are not reflected in values created prior to such a change.
  • This library does not create directories or check for their existence. The library only provides information on what the path to a certain directory should be. How this information is used is a decision that developers need to make based on the requirements of each individual application.
  • This library is intentionally focused on providing information on user-writable directories only. There is no discernible benefit in returning a path that points to a user-level, writable directory on one operating system, but a system-level, read-only directory on another, that would outweigh the confusion and unexpected failures such an approach would cause.
    • executable_dir is specified to provide the path to a user-writable directory for binaries. As such a directory only commonly exists on Linux, it returns None on macOS and Windows.
    • font_dir is specified to provide the path to a user-writable directory for fonts. As such a directory only exists on Linux and macOS, it returns None on Windows.
    • runtime_dir is specified to provide the path to a directory for non-essential runtime data. It is required that this directory is created when the user logs in, is only accessible by the user itself, is deleted when the user logs out, and supports all filesystem features of the operating system. As such a directory only commonly exists on Linux, it returns None on macOS and Windows.

Features

BaseDirs

The intended use case for BaseDirs is to query the paths of user-invisible standard directories that have been defined according to the conventions of the operating system the library is running on.

If you want to compute the location of cache, config or data directories for your own application or project, use ProjectDirs instead.

Function name Value on Linux Value on Windows Value on macOS
home_dir $HOME {FOLDERID_Profile} $HOME
cache_dir $XDG_CACHE_HOME or $HOME/.cache {FOLDERID_LocalAppData} $HOME/Library/Caches
config_dir $XDG_CONFIG_HOME or $HOME/.config {FOLDERID_RoamingAppData} $HOME/Library/Preferences
data_dir $XDG_DATA_HOME or $HOME/.local/share {FOLDERID_RoamingAppData} $HOME/Library/Application Support
data_local_dir $XDG_DATA_HOME or $HOME/.local/share {FOLDERID_LocalAppData} $HOME/Library/Application Support
executable_dir Some($XDG_BIN_HOME/../bin) or Some($XDG_DATA_HOME/../bin) or Some($HOME/.local/bin) None None
runtime_dir Some($XDG_RUNTIME_DIR) or None None None

UserDirs

The intended use case for UserDirs is to query the paths of user-facing standard directories that have been defined according to the conventions of the operating system the library is running on.

Function name Value on Linux Value on Windows Value on macOS
home_dir $HOME {FOLDERID_Profile} $HOME
audio_dir Some(XDG_MUSIC_DIR) or None Some({FOLDERID_Music}) Some($HOME/Music/)
desktop_dir Some(XDG_DESKTOP_DIR) or None Some({FOLDERID_Desktop}) Some($HOME/Desktop/)
document_dir Some(XDG_DOCUMENTS_DIR) or None Some({FOLDERID_Documents}) Some($HOME/Documents/)
download_dir Some(XDG_DOWNLOAD_DIR) or None Some({FOLDERID_Downloads}) Some($HOME/Downloads/)
font_dir Some($XDG_DATA_HOME/fonts/) or Some($HOME/.local/share/fonts/) None Some($HOME/Library/Fonts/)
picture_dir Some(XDG_PICTURES_DIR) or None Some({FOLDERID_Pictures}) Some($HOME/Pictures/)
public_dir Some(XDG_PUBLICSHARE_DIR) or None Some({FOLDERID_Public}) Some($HOME/Public/)
template_dir Some(XDG_TEMPLATES_DIR) or None Some({FOLDERID_Templates}) None
video_dir Some(XDG_VIDEOS_DIR) or None Some({FOLDERID_Videos}) Some($HOME/Movies/)

ProjectDirs

The intended use case for ProjectDirs is to compute the location of cache, config or data directories for your own application or project, which are derived from the standard directories.

Function name Value on Linux Value on Windows Value on macOS
cache_dir $XDG_CACHE_HOME/<project_path> or $HOME/.cache/<project_path> {FOLDERID_LocalAppData}/<project_path>/cache $HOME/Library/Caches/<project_path>
config_dir $XDG_CONFIG_HOME/<project_path> or $HOME/.config/<project_path> {FOLDERID_RoamingAppData}/<project_path>/config $HOME/Library/Preferences/<project_path>
data_dir $XDG_DATA_HOME/<project_path> or $HOME/.local/share/<project_path> {FOLDERID_RoamingAppData}/<project_path>/data $HOME/Library/Application Support/<project_path>
data_local_dir $XDG_DATA_HOME/<project_path> or $HOME/.local/share/<project_path> {FOLDERID_LocalAppData}/<project_path>/data $HOME/Library/Application Support/<project_path>
runtime_dir Some($XDG_RUNTIME_DIR/_project_path_) None None

The specific value of <project_path> is computed by the

ProjectDirs::from(qualifier: &str,
                  organization: &str,
                  application: &str)

function and varies across operating systems. As an example, calling

ProjectDirs::from("org"         /*qualifier*/,
                  "Baz Corp"    /*organization*/,
                  "Foo Bar-App" /*application*/)

results in the following values:

Value on Linux Value on Windows Value on macOS
"foobar-app" "Baz Corp/Foo Bar-App" "org.Baz-Corp.Foo-Bar-App"

The ProjectDirs::from_path function allows the creation of ProjectDirs structs directly from a PathBuf value. This argument is used verbatim and is not adapted to operating system standards. The use of ProjectDirs::from_path is strongly discouraged, as its results will not follow operating system standards on at least two of three platforms.

Comparison

There are other crates in the Rust ecosystem that try similar or related things. Here is an overview of them, combined with ratings on properties that guided the design of this crate.

Please take this table with a grain of salt: a different crate might very well be more suitable for your specific use case. (Of course my crate achieves my design goals better than other crates, which might have had different design goals.)

Library Status Lin Mac Win Base User Proj Conv
app_dirs Unmaintained 🞈
app_dirs2 Maintained 🞈
dirs Developed
directories Developed
s_app_dir Unmaintained? 🞈 🞈
standard_paths Maintained
xdg Maintained 🞈
xdg-basedir Unmaintained? 🞈
xdg-rs Obsolete 🞈

Build

It's possible to cross-compile this library if the necessary toolchains are installed with rustup. This is helpful to ensure a change has not broken compilation on a different platform.

The following commands will build this library on Linux, macOS and Windows:

cargo build --target=x86_64-unknown-linux-gnu
cargo build --target=x86_64-pc-windows-gnu
cargo build --target=x86_64-apple-darwin
cargo build --target=x86_64-unknown-redox

Changelog

2

The behavior of deactivated, missing or invalid XDG User Dirs entries on Linux has been improved (contributed by @tmiasko, thank you!):

  • Version 1 returned the user's home directory (Some($HOME)) for such faulty entries, except for a faulty XDG_DESKTOP_DIR entry which returned (Some($HOME/Desktop)).
  • Version 2 returns None for such entries.

License

Licensed under either of

at your option.

Contribution

Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in the work by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.