feat(oci): add saveToArchive method to VMDirectory

Sources/tart/VMDirectory+OCIArchive.swift

@@ -0,0 +1,47 @@
+import Foundation
+
+extension VMDirectory {
+  func saveToArchive(path: String, concurrency: UInt, labels: [String: String] = [:], tag: String? = nil) async throws {
+    let archive = try OCIArchiveWriter()
+
+    var layers = [OCIManifestLayer]()
+
+    let config = try VMConfig(fromURL: configURL)
+    var labels = labels
+    labels[diskFormatLabel] = config.diskFormat.rawValue
+    let configJSON = try JSONEncoder().encode(config)
+    defaultLogger.appendNewLine("saving config...")
+    let configDigest = try await archive.pushBlob(fromData: configJSON, chunkSizeMb: 0, digest: nil)
+    layers.append(OCIManifestLayer(mediaType: configMediaType, size: configJSON.count, digest: configDigest))
+
+    let diskSize = try FileManager.default.attributesOfItem(atPath: diskURL.path)[.size] as! Int64
+    defaultLogger.appendNewLine("saving disk... this will take a while...")
+    let progress = Progress(totalUnitCount: diskSize)
+    ProgressObserver(progress).log(defaultLogger)
+
+    layers.append(contentsOf: try await DiskV2.push(diskURL: diskURL, registry: archive, chunkSizeMb: 0, concurrency: concurrency, progress: progress))
+
+    defaultLogger.appendNewLine("saving NVRAM...")
+    let nvram = try FileHandle(forReadingFrom: nvramURL).readToEnd()!
+    let nvramDigest = try await archive.pushBlob(fromData: nvram, chunkSizeMb: 0, digest: nil)
+    layers.append(OCIManifestLayer(mediaType: nvramMediaType, size: nvram.count, digest: nvramDigest))
+
+    let ociConfigContainer = OCIConfig.ConfigContainer(Labels: labels)
+    let ociConfigJSON = try OCIConfig(architecture: config.arch, os: config.os, config: ociConfigContainer).toJSON()
+    let ociConfigDigest = try await archive.pushBlob(fromData: ociConfigJSON, chunkSizeMb: 0, digest: nil)
+    let manifest = OCIManifest(
+      config: OCIManifestConfig(size: ociConfigJSON.count, digest: ociConfigDigest),
+      layers: layers,
+      uncompressedDiskSize: UInt64(diskSize),
+      uploadDate: Date()
+    )
+
+    let tagRef = tag ?? "latest"
+    defaultLogger.appendNewLine("saving manifest...")
+    _ = try await archive.pushManifest(reference: tagRef, manifest: manifest)
+
+    try archive.finalize(path: path, tag: tagRef)
+
+    defaultLogger.appendNewLine("saved to \(path)")
+  }
+}