Registry: use issued_at field in the token response message (#65)

* Registry: use issued_at field in the token response message

* Configure JSONDecoder instead of the Decodable itself

.goreleaser.yml

@@ -35,3 +35,5 @@ brews:
     homepage: https://github.com/cirruslabs/tart
     description: Run macOS VMs on Apple Silicon
     skip_upload: auto
+    custom_block: |
+      depends_on :macos => :monterey

README.md

@@ -8,7 +8,7 @@ Built by CI engineers for your automation needs. Here are some highlights of Tar
 * Use Tart Packer Plugin to automate VM creation.
 * Built-in CI integration.
 
-Try running a Tart VM on your Apple Silicon device (will download a 25 GB image):
+Try running a Tart VM on your Apple Silicon device running macOS Monterey or later (will download a 25 GB image):
 
 ```shell
 brew install cirruslabs/cli/tart
@@ -78,7 +78,7 @@ Please refer to `tart set --help` for additional details.
 
 ### Building with Packer
 
-Please refer to [Tart Packer Plugin reposiotry](https://github.com/cirruslabs/packer-plugin-tart) for setup instructions.
+Please refer to [Tart Packer Plugin repository](https://github.com/cirruslabs/packer-plugin-tart) for setup instructions.
 Here is an example of a template to build `monterey-base` local image based of a remote image:
 
 ```json
@@ -160,3 +160,23 @@ tart pull acme.io/remoteorg/name:latest my-local-vm-name
   Tart is a relatively small project, and it didn't feel right to try to monetize it.
   Apple did all the heavy lifting with their `Virtualization.Framework`.
 </details>
+
+<details>
+  <summary>How to change VM's disk size?</summary>
+
+  You can choose disk size upon creation of a virtual machine:
+
+  ```shell
+  tart create --from-ipsw=latest --disk-size=25 monterey-vanilla
+  ```
+
+  For an existing VM please use [Packer Plugin](https://github.com/cirruslabs/packer-plugin-tart) which can increase
+  disk size for new virtual machines. Here is an example of [how to change disk size in a Packer template](https://github.com/cirruslabs/macos-image-templates/blob/fb0bcf68e0b093129136875c050205a66729b596/templates/base.pkr.hcl#L15).
+</details>
+
+<details>
+  <summary>Nested virtualization support?</summary>
+
+  Tart is limited by functionality of Apple's `Virtualization.Framework`. At the moment `Virtualization.Framework`
+  doesn't support nested virtualization.
+</details>

Sources/tart/OCI/Registry.swift

@@ -8,11 +8,31 @@ enum RegistryError: Error {
 }
 
 struct TokenResponse: Decodable {
-  let creationTime = Date()
-  
+  let defaultIssuedAt = Date()
+  let defaultExpiresIn = 60
+
   var token: String
-  var expires_in: Int?
-  
+  var expiresIn: Int?
+  var issuedAt: Date?
+
+  static func parse(fromData: Data) throws -> Self {
+    let decoder = JSONDecoder()
+
+    decoder.keyDecodingStrategy = .convertFromSnakeCase
+
+    // RFC3339 date formatter from Apple's documentation[1]
+    //
+    // [1]: https://developer.apple.com/documentation/foundation/dateformatter
+    let dateFormatter = DateFormatter()
+    dateFormatter.locale = Locale(identifier: "en_US_POSIX")
+    dateFormatter.dateFormat = "yyyy-MM-dd'T'HH:mm:ssZZZZZ"
+    dateFormatter.timeZone = TimeZone(secondsFromGMT: 0)
+
+    decoder.dateDecodingStrategy = .formatted(dateFormatter)
+
+    return try decoder.decode(TokenResponse.self, from: fromData)
+  }
+
   var tokenExpiresAt: Date {
     get {
       // Tokens can expire and expire_in field is used to determine when:
@@ -22,8 +42,8 @@ struct TokenResponse: Decodable {
       // >a token should never be returned with less than 60 seconds to live.
       //
       // [1]: https://docs.docker.com/registry/spec/auth/token/#requesting-a-token
-      
-      creationTime + TimeInterval(expires_in ?? 60)
+
+      (issuedAt ?? defaultIssuedAt) + TimeInterval(expiresIn ?? defaultExpiresIn)
     }
   }
   
@@ -233,7 +253,7 @@ class Registry {
         + "while retrieving an authentication token", details: String(decoding: tokenResponseRaw, as: UTF8.self))
     }
 
-    currentAuthToken = try JSONDecoder().decode(TokenResponse.self, from: tokenResponseRaw)
+    currentAuthToken = try TokenResponse.parse(fromData: tokenResponseRaw)
   }
 
   private func authAwareRequest(request: URLRequest) async throws -> (Data, HTTPURLResponse) {

Sources/tart/VMDirectory+OCI.swift

@@ -52,8 +52,10 @@ extension VMDirectory {
     }
 
     // Progress
-    defaultLogger.appendNewLine("pulling disk...")
-    let progress = Progress(totalUnitCount: Int64(diskLayers.map{ $0.size }.reduce(0) { $0 + $1 }))
+    let diskCompressedSize: Int64 = Int64(diskLayers.map {$0.size}.reduce(0) {$0 + $1})
+    let prettyDiskSize = String(format: "%.1f", Double(diskCompressedSize) / 1_000_000_000.0)
+    defaultLogger.appendNewLine("pulling disk (\(prettyDiskSize) GB compressed)...")
+    let progress = Progress(totalUnitCount: diskCompressedSize)
     ProgressObserver(progress).log(defaultLogger)
 
     for diskLayer in diskLayers {

Tests/TartTests/TokenResponseTests.swift

@@ -0,0 +1,38 @@
+import XCTest
+@testable import tart
+
+final class TokenResponseTests: XCTestCase {
+  func testBasic() throws {
+    let tokenResponseRaw = Data("{\"token\":\"some token\"}".utf8)
+    let tokenResponse = try TokenResponse.parse(fromData: tokenResponseRaw)
+
+    XCTAssertEqual(tokenResponse.token, "some token")
+
+    let expectedTokenExpiresAtRange = Date()...Date().addingTimeInterval(60)
+    XCTAssertTrue(expectedTokenExpiresAtRange.contains(tokenResponse.tokenExpiresAt))
+
+    XCTAssertTrue(tokenResponse.isValid)
+  }
+
+  func testExpirationBasic() throws {
+    let tokenResponseRaw = Data("{\"token\":\"some token\",\"expires_in\":2}".utf8)
+    let tokenResponse = try TokenResponse.parse(fromData: tokenResponseRaw)
+
+    XCTAssertEqual(tokenResponse.expiresIn, 2)
+
+    let expectedTokenExpiresAtRange = Date()...Date().addingTimeInterval(2)
+    XCTAssertTrue(expectedTokenExpiresAtRange.contains(tokenResponse.tokenExpiresAt))
+
+    XCTAssertTrue(tokenResponse.isValid)
+    _ = XCTWaiter.wait(for: [expectation(description: "Wait 3 seconds for the token to become invalid")], timeout: 2)
+    XCTAssertFalse(tokenResponse.isValid)
+  }
+
+  func testExpirationWithIssuedAt() throws {
+    let tokenResponseRaw = Data("{\"token\":\"some token\",\"expires_in\":3600,\"issued_at\":\"1970-01-01T00:00:00Z\"}".utf8)
+    let tokenResponse = try TokenResponse.parse(fromData: tokenResponseRaw)
+
+    XCTAssertEqual(Date(timeIntervalSince1970: 3600), tokenResponse.tokenExpiresAt)
+    XCTAssertFalse(tokenResponse.isValid)
+  }
+}