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euanheuanh
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ContainerRegistry: Add TarImageDestination
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‎Sources/ContainerRegistry/TarImageDestination.swift‎

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Original file line numberDiff line numberDiff line change
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//===----------------------------------------------------------------------===//
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//
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// This source file is part of the SwiftContainerPlugin open source project
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//
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// Copyright (c) 2025 Apple Inc. and the SwiftContainerPlugin project authors
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// Licensed under Apache License v2.0
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//
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// See LICENSE.txt for license information
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// See CONTRIBUTORS.txt for the list of SwiftContainerPlugin project authors
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//
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// SPDX-License-Identifier: Apache-2.0
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//
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//===----------------------------------------------------------------------===//
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import struct Foundation.Data
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import class Foundation.OutputStream
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import class Foundation.JSONDecoder
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import class Foundation.JSONEncoder
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import Tar
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/// A tar file on disk, to which a container image can be saved.
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public class TarImageDestination {
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public var decoder: JSONDecoder
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var encoder: JSONEncoder
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var archive: Archive
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/// Creates a new TarImageDestination
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/// - Parameters stream: OutputStream to which the archive should be written
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/// - Throws: If an error occurs when serializing archive.
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public init(toStream stream: OutputStream) throws {
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self.archive = Archive(toStream: stream)
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self.decoder = JSONDecoder()
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self.encoder = containerJSONEncoder()
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try archive.appendFile(name: "oci-layout", data: [UInt8](encoder.encode(ImageLayoutHeader())))
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try archive.appendDirectory(name: "blobs")
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try archive.appendDirectory(name: "blobs/sha256")
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}
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}
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extension TarImageDestination: ImageDestination {
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/// Saves a blob of unstructured data to the destination.
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/// - Parameters:
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/// - repository: Name of the destination repository.
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/// - mediaType: mediaType field for returned ContentDescriptor.
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/// - data: Object to be saved.
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/// - Returns: An ContentDescriptor object representing the
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/// saved blob.
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/// - Throws: If the blob cannot be encoded or the save fails.
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public func putBlob(
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repository: ImageReference.Repository,
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mediaType: String,
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data: Data
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) async throws -> ContentDescriptor {
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let digest = ImageReference.Digest(of: Data(data))
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try archive.appendFile(name: "\(digest.value)", prefix: "blobs/\(digest.algorithm)", data: [UInt8](data))
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return .init(mediaType: mediaType, digest: "\(digest)", size: Int64(data.count))
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}
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/// Saves a JSON object to the destination, serialized as an unstructured blob.
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/// - Parameters:
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/// - repository: Name of the destination repository.
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/// - mediaType: mediaType field for returned ContentDescriptor.
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/// - data: Object to be saved.
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/// - Returns: An ContentDescriptor object representing the
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/// saved blob.
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/// - Throws: If the blob cannot be encoded or the save fails.
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public func putBlob<Body: Encodable>(
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repository: ImageReference.Repository,
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mediaType: String,
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data: Body
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) async throws -> ContentDescriptor {
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let encoded = try encoder.encode(data)
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return try await putBlob(repository: repository, mediaType: mediaType, data: encoded)
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}
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/// Checks whether a blob exists.
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///
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/// - Parameters:
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/// - repository: Name of the destination repository.
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/// - digest: Digest of the requested blob.
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/// - Returns: Always returns False.
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/// - Throws: If the destination encounters an error.
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public func blobExists(
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repository: ImageReference.Repository,
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digest: ImageReference.Digest
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) async throws -> Bool {
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false
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}
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/// Encodes and saves an image manifest.
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///
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/// - Parameters:
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/// - repository: Name of the destination repository.
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/// - reference: Optional tag to apply to this manifest.
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/// - manifest: Manifest to be saved.
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/// - Returns: An ContentDescriptor object representing the
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/// saved blob.
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/// - Throws: If the blob cannot be encoded or saved.
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public func putManifest(
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repository: ImageReference.Repository,
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reference: (any ImageReference.Reference)?,
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manifest: ImageManifest
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) async throws -> ContentDescriptor {
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// Manifests are not special in the on-disk representation - they are just stored as blobs
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try await self.putBlob(
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repository: repository,
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mediaType: "application/vnd.oci.image.manifest.v1+json",
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data: manifest
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)
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}
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/// Encodes and saves an image index.
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///
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/// - Parameters:
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/// - repository: Name of the destination repository.
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/// - reference: Optional tag to apply to this index.
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/// - index: Index to be saved.
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/// - Returns: An ContentDescriptor object representing the
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/// saved index.
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/// - Throws: If the index cannot be encoded or saving fails.
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public func putIndex(
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repository: ImageReference.Repository,
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reference: (any ImageReference.Reference)?,
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index: ImageIndex
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) async throws -> ContentDescriptor {
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// Unlike Manifest, Index is not written as a blob
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let encoded = try encoder.encode(index)
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let digest = ImageReference.Digest(of: encoded)
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let mediaType = index.mediaType ?? "application/vnd.oci.image.index.v1+json"
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try archive.appendFile(name: "index.json", data: [UInt8](encoded))
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try archive.appendFile(name: "\(digest.value)", prefix: "blobs/\(digest.algorithm)", data: [UInt8](encoded))
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return .init(mediaType: mediaType, digest: "\(digest)", size: Int64(encoded.count))
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}
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}
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struct ImageLayoutHeader: Codable {
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var imageLayoutVersion: String = "1.0.0"
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}

‎Sources/Tar/tar.swift‎

Lines changed: 2 additions & 2 deletions
Original file line numberDiff line numberDiff line change
@@ -349,8 +349,8 @@ public struct Archive: ~Copyable {
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var output: OutputStream
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/// Creates an empty Archive
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public init() {
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output = OutputStream.toMemory()
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public init(toStream: OutputStream = .toMemory()) {
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output = toStream
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output.open()
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output.schedule(in: .current, forMode: .default) // is this needed?
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}

‎Sources/containertool/containertool.swift‎

Lines changed: 21 additions & 6 deletions
Original file line numberDiff line numberDiff line change
@@ -43,6 +43,9 @@ enum AllowHTTP: String, ExpressibleByArgument, CaseIterable { case source, desti
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@Option(help: "The base container image name and optional tag")
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var from: String?
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@Option(name: [.long, .short], help: "File in which the container image should be saved")
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var output: URL
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}
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@OptionGroup(title: "Source and destination repository options")
@@ -203,12 +206,17 @@ enum AllowHTTP: String, ExpressibleByArgument, CaseIterable { case source, desti
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if verbose { log("Connected to source registry: \(baseImage.registry)") }
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}
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let destination = try await RegistryClient(
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registry: destinationImage.registry,
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insecure: authenticationOptions.allowInsecureHttp == .destination
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|| authenticationOptions.allowInsecureHttp == .both,
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auth: .init(username: username, password: password, auth: authProvider)
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)
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// let destination = try await RegistryClient(
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// registry: destinationImage.registry,
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// insecure: authenticationOptions.allowInsecureHttp == .destination
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// || authenticationOptions.allowInsecureHttp == .both,
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// auth: .init(username: username, password: password, auth: authProvider)
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// )
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guard let saveStream = OutputStream(url: repositoryOptions.output, append: false) else {
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fatalError("failed to create tarball")
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}
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let destination = try TarImageDestination(toStream: saveStream)
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if verbose { log("Connected to destination registry: \(destinationImage.registry)") }
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if verbose { log("Using base image: \(baseImage)") }
@@ -231,3 +239,10 @@ enum AllowHTTP: String, ExpressibleByArgument, CaseIterable { case source, desti
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print(finalImage)
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}
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}
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// Parse URL path arguments
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extension Foundation.URL: ArgumentParser.ExpressibleByArgument {
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public init?(argument: String) {
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self.init(fileURLWithPath: argument)
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}
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}

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