Convert Storage Task implementation to Swift

FirebaseStorage.podspec

@@ -33,7 +33,7 @@ Firebase Storage provides robust, secure file uploads and downloads from Firebas
   s.prefix_header_file = false
 
   s.source_files = [
-    'FirebaseStorage/Sources/*.swift',
+    'FirebaseStorage/Sources/**/*.swift',
     'FirebaseStorage/Typedefs/*.h',
   ]
 
@@ -42,6 +42,7 @@ Firebase Storage provides robust, secure file uploads and downloads from Firebas
   s.dependency 'FirebaseAuthInterop', '~> 9.0'
   s.dependency 'FirebaseCore', '~> 9.0'
   s.dependency 'FirebaseCoreExtension', '~> 9.0'
+  s.dependency 'GTMSessionFetcher/Core', '>= 1.7', '< 3.0'
 
   s.test_spec 'ObjCIntegration' do |objc_tests|
     objc_tests.scheme = { :code_coverage => true }

FirebaseStorage/Sources/Internal/StorageDeleteTask.swift

@@ -0,0 +1,81 @@
+// Copyright 2022 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+import Foundation
+
+import FirebaseStorageInternal
+#if COCOAPODS
+  import GTMSessionFetcher
+#else
+  import GTMSessionFetcherCore
+#endif
+
+/**
+ * Task which provides the ability to delete an object in Firebase Storage.
+ */
+internal class StorageDeleteTask: StorageTask, StorageTaskManagement {
+  private var fetcher: GTMSessionFetcher?
+  private var fetcherCompletion: ((Data?, NSError?) -> Void)?
+  private var taskCompletion: ((_ error: Error?) -> Void)?
+
+  internal init(reference: FIRIMPLStorageReference,
+                fetcherService: GTMSessionFetcherService,
+                queue: DispatchQueue,
+                completion: ((_: Error?) -> Void)?) {
+    super.init(reference: reference, service: fetcherService, queue: queue)
+    taskCompletion = completion
+  }
+
+  deinit {
+    self.fetcher?.stopFetching()
+  }
+
+  /**
+   * Prepares a task and begins execution.
+   */
+  internal func enqueue() {
+    weak var weakSelf = self
+    DispatchQueue.global(qos: .background).async {
+      guard let strongSelf = weakSelf else { return }
+      strongSelf.state = .queueing
+      var request = strongSelf.baseRequest
+      request.httpMethod = "DELETE"
+      request.timeoutInterval = strongSelf.reference.storage.maxOperationRetryTime
+
+      let callback = strongSelf.taskCompletion
+      strongSelf.taskCompletion = nil
+
+      let fetcher = strongSelf.fetcherService.fetcher(with: request)
+      fetcher.comment = "DeleteTask"
+      strongSelf.fetcher = fetcher
+
+      strongSelf.fetcherCompletion = { (data: Data?, error: NSError?) in
+        if let error = error, self.error == nil {
+          self.error = StorageErrorCode.error(withServerError: error, ref: strongSelf.reference)
+        }
+        if let callback = callback {
+          callback(self.error)
+        }
+        self.fetcherCompletion = nil
+      }
+
+      strongSelf.fetcher?.beginFetch { data, error in
+        let strongSelf = weakSelf
+        if let fetcherCompletion = strongSelf?.fetcherCompletion {
+          fetcherCompletion(data, error as? NSError)
+        }
+      }
+    }
+  }
+}

FirebaseStorage/Sources/Internal/StorageGetDownloadURLTask.swift

@@ -0,0 +1,121 @@
+// Copyright 2022 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+import Foundation
+
+import FirebaseStorageInternal
+#if COCOAPODS
+  import GTMSessionFetcher
+#else
+  import GTMSessionFetcherCore
+#endif
+
+/**
+ * Task which provides the ability to get a download URL for an object in Firebase Storage.
+ */
+internal class StorageGetDownloadURLTask: StorageTask, StorageTaskManagement {
+  private var fetcher: GTMSessionFetcher?
+  private var fetcherCompletion: ((Data?, NSError?) -> Void)?
+  private var taskCompletion: ((_ downloadURL: URL?, _: Error?) -> Void)?
+
+  internal init(reference: FIRIMPLStorageReference,
+                fetcherService: GTMSessionFetcherService,
+                queue: DispatchQueue,
+                completion: ((_: URL?, _: Error?) -> Void)?) {
+    super.init(reference: reference, service: fetcherService, queue: queue)
+    taskCompletion = completion
+  }
+
+  deinit {
+    self.fetcher?.stopFetching()
+  }
+
+  /**
+   * Prepares a task and begins execution.
+   */
+  internal func enqueue() {
+    weak var weakSelf = self
+    DispatchQueue.global(qos: .background).async {
+      guard let strongSelf = weakSelf else { return }
+      var request = strongSelf.baseRequest
+      request.httpMethod = "GET"
+      request.timeoutInterval = strongSelf.reference.storage.maxOperationRetryTime
+
+      let callback = strongSelf.taskCompletion
+      strongSelf.taskCompletion = nil
+
+      let fetcher = strongSelf.fetcherService.fetcher(with: request)
+      fetcher.comment = "GetDownloadURLTask"
+      strongSelf.fetcher = fetcher
+
+      strongSelf.fetcherCompletion = { (data: Data?, error: NSError?) in
+        var downloadURL: URL?
+        if let error = error {
+          if self.error == nil {
+            self.error = StorageErrorCode.error(withServerError: error, ref: self.reference)
+          }
+        } else {
+          if let data = data,
+             let responseDictionary = try? JSONSerialization
+             .jsonObject(with: data) as? [String: String] {
+            downloadURL = strongSelf.downloadURLFromMetadataDictionary(responseDictionary)
+            if downloadURL == nil {
+              self.error = NSError(domain: StorageErrorDomain,
+                                   code: StorageErrorCode.unknown.rawValue,
+                                   userInfo: [NSLocalizedDescriptionKey:
+                                     "Failed to retrieve a download URL."])
+            }
+          } else {
+            self.error = StorageErrorCode.error(withInvalidRequest: data)
+          }
+        }
+        if let callback = callback {
+          callback(downloadURL, self.error)
+        }
+        self.fetcherCompletion = nil
+      }
+
+      strongSelf.fetcher?.beginFetch { data, error in
+        let strongSelf = weakSelf
+        if let fetcherCompletion = strongSelf?.fetcherCompletion {
+          fetcherCompletion(data, error as? NSError)
+        }
+      }
+    }
+  }
+
+  internal func downloadURLFromMetadataDictionary(_ dictionary: [String: String]) -> URL? {
+    let downloadTokens = dictionary["downloadTokens"]
+    guard let downloadTokens = downloadTokens,
+          downloadTokens.count > 0 else {
+      return nil
+    }
+    let downloadTokenArray = downloadTokens.components(separatedBy: ",")
+    let bucket = dictionary["bucket"] ?? "<error: missing bucket>"
+    let path = dictionary["name"] ?? "<error: missing path name>"
+    let fullPath = "/v0/b/\(bucket)/o/\(StorageUtils.GCSEscapedString(path))"
+    var components = URLComponents()
+    components.scheme = reference.storage.scheme
+    components.host = reference.storage.host
+    components.port = reference.storage.port
+    components.percentEncodedPath = fullPath
+
+    // The backend can return an arbitrary number of download tokens, but we only expose the first
+    // token via the download URL.
+    let altItem = URLQueryItem(name: "alt", value: "media")
+    let tokenItem = URLQueryItem(name: "token", value: downloadTokenArray[0])
+    components.queryItems = [altItem, tokenItem]
+    return components.url
+  }
+}

FirebaseStorage/Sources/Internal/StorageGetMetadataTask.swift

@@ -0,0 +1,93 @@
+// Copyright 2022 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+import Foundation
+
+import FirebaseStorageInternal
+#if COCOAPODS
+  import GTMSessionFetcher
+#else
+  import GTMSessionFetcherCore
+#endif
+
+/**
+ * Task which provides the ability to delete an object in Firebase Storage.
+ */
+internal class StorageGetMetadataTask: StorageTask, StorageTaskManagement {
+  private var fetcher: GTMSessionFetcher?
+  private var fetcherCompletion: ((Data?, NSError?) -> Void)?
+  private var taskCompletion: ((_ metadata: StorageMetadata?, _: Error?) -> Void)?
+
+  internal init(reference: FIRIMPLStorageReference,
+                fetcherService: GTMSessionFetcherService,
+                queue: DispatchQueue,
+                completion: ((_: StorageMetadata?, _: Error?) -> Void)?) {
+    super.init(reference: reference, service: fetcherService, queue: queue)
+    taskCompletion = completion
+  }
+
+  deinit {
+    self.fetcher?.stopFetching()
+  }
+
+  /**
+   * Prepares a task and begins execution.
+   */
+  internal func enqueue() {
+    weak var weakSelf = self
+    DispatchQueue.global(qos: .background).async {
+      guard let strongSelf = weakSelf else { return }
+      strongSelf.state = .queueing
+      var request = strongSelf.baseRequest
+      request.httpMethod = "GET"
+      request.timeoutInterval = strongSelf.reference.storage.maxOperationRetryTime
+
+      let callback = strongSelf.taskCompletion
+      strongSelf.taskCompletion = nil
+
+      let fetcher = strongSelf.fetcherService.fetcher(with: request)
+      fetcher.comment = "GetMetadataTask"
+      strongSelf.fetcher = fetcher
+
+      strongSelf.fetcherCompletion = { (data: Data?, error: NSError?) in
+        var metadata: StorageMetadata?
+        if let error = error {
+          if self.error == nil {
+            self.error = StorageErrorCode.error(withServerError: error, ref: self.reference)
+          }
+        } else {
+          if let data = data,
+             let responseDictionary = try? JSONSerialization
+             .jsonObject(with: data) as? [String: Any] {
+            metadata = StorageMetadata(dictionary: responseDictionary)
+            metadata?.impl.type = .file
+          } else {
+            self.error = StorageErrorCode.error(withInvalidRequest: data)
+          }
+        }
+        if let callback = callback {
+          callback(metadata, self.error)
+        }
+        self.fetcherCompletion = nil
+      }
+
+      strongSelf.fetcher?.beginFetch { data, error in
+        let strongSelf = weakSelf
+        if let fetcherCompletion = strongSelf?.fetcherCompletion {
+          fetcherCompletion(data, error as? NSError)
+        }
+      }
+    }
+  }
+}