Crate oci_unpack 

This crate implements the basic support to download and unpack OCI images stored in a container registry.

It is not expected to support every feature in the OCI specifications. Instead, the goal is to implement all features used in the most common images.

Usage

The first step for unpacking an OCI image is to get a reference instance to describe its location:

let reference = Reference::try_from("debian:stable").unwrap();

The string is parsed following the same rules as the docker pull command, as described in the Reference documentation.

Then, an Unpacker instance is created to configure how to download and unpack the referenced image.

Unpacker::new(reference).unpack("/tmp/image").unwrap();

An instance of EventHandler can be used to receive notifications during the download/unpack process. The file examples/unpack.rs in the repository has a full implementation of a handler.

Sandbox

Before creating any file in the target directory, Unpacker::unpack tries to create a sandbox with Landlock, so the process will be able to create files only beneath the target directory.

Errors on creating the sandbox can be ignored by setting Unpacker::require_sandbox to false.

The sandbox is only available if the crate is built with the sandbox feature, which is enabled by default.

Zstd Compression

The zstd feature (enabled by default) is required to support images compressed with zstd.

Modules

errors

Errors from the functions in the public API.

Structs

Digest

A digest to validate a blob.

NoEventHandler

EventHandler instance to ignore all events.

Reference

Reference to an image in an OCI registry.

Repository

Represents a repository name, like library/debian or nixos/nix.

Unpacker

Download an image and unpack its contents to a new directory.

Enums

DigestAlgorithm

Algorithm to compute the hash value.

MediaType

Known media types.

Traits

EventHandler

Handler to receive notifications for events during the unpack process.