Add ability to download Xcode without logging in using XcodeRelease

Sources/XcodesKit/Models.swift

@@ -50,6 +50,10 @@ public struct Xcode: Codable, Equatable {
     public let filename: String
     public let releaseDate: Date?
 
+    public var downloadPath: String {
+        return url.path
+    }
+
     public init(version: Version, url: URL, filename: String, releaseDate: Date?) {
         self.version =  version
         self.url = url

Sources/XcodesKit/URLRequest+Apple.swift

@@ -4,6 +4,7 @@ extension URL {
     static let download = URL(string: "https://developer.apple.com/download")!
     static let downloads = URL(string: "https://developer.apple.com/services-account/QH65B2/downloadws/listDownloads.action")!
     static let downloadXcode = URL(string: "https://developer.apple.com/devcenter/download.action")!
+    static let downloadADCAuth = URL(string: "https://developerservices2.apple.com/services/download")!
 }
 
 extension URLRequest {
@@ -25,4 +26,14 @@ extension URLRequest {
         request.allHTTPHeaderFields?["Accept"] = "*/*"
         return request
     }
+
+    // default to a known download path if none passed in
+    static func downloadADCAuth(path: String? = "/Developer_Tools/Xcode_14/Xcode_14.xip") -> URLRequest {
+        var components = URLComponents(url: .downloadADCAuth, resolvingAgainstBaseURL: false)!
+        components.queryItems = [URLQueryItem(name: "path", value: path)]
+        var request = URLRequest(url: components.url!)
+        request.allHTTPHeaderFields = request.allHTTPHeaderFields ?? [:]
+        request.allHTTPHeaderFields?["Accept"] = "*/*"
+        return request
+    }
 }

Sources/XcodesKit/XcodeInstaller.swift

@@ -287,7 +287,15 @@ public final class XcodeInstaller {
 
     private func downloadXcode(version: Version, dataSource: DataSource, downloader: Downloader, willInstall: Bool) -> Promise<(Xcode, URL)> {
         return firstly { () -> Promise<Version> in
-            loginIfNeeded().map { version }
+            if dataSource == .apple {
+                return loginIfNeeded().map { version }
+            } else {
+                guard let xcode = self.xcodeList.availableXcodes.first(withVersion: version) else {
+                    throw Error.unavailableVersion(version)
+                }
+
+                return validateADCSession(path: xcode.downloadPath).map { version }
+            }
         }
         .then { version -> Promise<Version> in
             if self.xcodeList.shouldUpdate {
@@ -297,14 +305,6 @@ public final class XcodeInstaller {
                 return Promise.value(version)
             }
         }
-        .then { version -> Promise<Version> in
-            // This request would've already been made if the Apple data source were being used.
-            // That's not the case for the Xcode Releases data source.
-            // We need the cookies from its response in order to download Xcodes though,
-            // so perform it here first just to be sure.
-            Current.network.dataTask(with: URLRequest.downloads)
-                .map { _ in version }
-        }
         .then { version -> Promise<(Xcode, URL)> in
             guard let xcode = self.xcodeList.availableXcodes.first(withVersion: version) else {
                 throw Error.unavailableVersion(version)
@@ -334,7 +334,11 @@ public final class XcodeInstaller {
                 .map { return (xcode, $0) }
         }
     }
-
+
+    func validateADCSession(path: String) -> Promise<Void> {
+        return Current.network.dataTask(with: URLRequest.downloadADCAuth(path: path)).asVoid()
+    }
+
     func loginIfNeeded(withUsername providedUsername: String? = nil, shouldPromptForPassword: Bool = false) -> Promise<Void> {
         return firstly { () -> Promise<Void> in
             return Current.network.validateSession()
@@ -626,11 +630,15 @@ public final class XcodeInstaller {
     }
 
     func update(dataSource: DataSource) -> Promise<[Xcode]> {
-        return firstly { () -> Promise<Void> in
-            loginIfNeeded()
-        }
-        .then { () -> Promise<[Xcode]> in
-            self.xcodeList.update(dataSource: dataSource)
+        if dataSource == .apple {
+            return firstly { () -> Promise<Void> in
+                loginIfNeeded()
+            }
+            .then { () -> Promise<[Xcode]> in
+                self.xcodeList.update(dataSource: dataSource)
+            }
+        } else {
+            return self.xcodeList.update(dataSource: dataSource)
         }
     }