Add Swift Result type APIs to Storage (#5225)

Author: paulb777

FirebaseStorage/Tests/SwiftIntegration/StorageIntegration.swift

@@ -1,4 +1,4 @@
-// Copyright 2020 Google
+// Copyright 2020 Google LLC
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.

FirebaseStorageSwift.podspec

@@ -0,0 +1,44 @@
+Pod::Spec.new do |s|
+  s.name                    = 'FirebaseStorageSwift'
+  s.version                 = '0.1.0'
+  s.summary                 = 'Swift Extensions for Google Cloud Storage'
+
+  s.description      = <<-DESC
+Firebase Storage provides robust, secure file uploads and downloads from Firebase SDKs, powered by Google Cloud Storage.
+                       DESC
+
+
+  s.homepage                = 'https://developers.google.com/'
+  s.license                 = { :type => 'Apache', :file => 'LICENSE' }
+  s.authors                 = 'Google, Inc.'
+
+  s.source                  = {
+    :git => 'https://github.com/Firebase/firebase-ios-sdk.git',
+    :tag => 'StorageSwift-' + s.version.to_s
+  }
+
+  s.swift_version           = '5.0'
+  s.ios.deployment_target   = '8.0'
+  s.osx.deployment_target   = '10.11'
+  s.tvos.deployment_target  = '10.0'
+  s.watchos.deployment_target = '6.0'
+
+  s.cocoapods_version       = '>= 1.4.0'
+  s.static_framework        = true
+  s.prefix_header_file      = false
+
+  s.source_files = [
+    'FirebaseStorageSwift/Sources/*.swift',
+  ]
+
+  s.dependency 'FirebaseStorage', '~> 3.6'
+
+  s.test_spec 'integration' do |int_tests|
+    int_tests.platforms = {:ios => '8.0', :osx => '10.11', :tvos => '10.0'}
+    int_tests.source_files = 'FirebaseStorageSwift/Tests/Integration/*.swift'
+    int_tests.requires_app_host = true
+    # Resources are shared with FirebaseStorage's integration tests.
+    int_tests.resources = 'FirebaseStorage/Tests/Integration/Resources/1mb.dat',
+                          'FirebaseStorage/Tests/Integration/Resources/GoogleService-Info.plist'
+  end
+end

FirebaseStorageSwift/Sources/SwiftAPIExtension.swift

@@ -0,0 +1,96 @@
+// Copyright 2020 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 FirebaseStorage
+
+/// getResultCallback generates a closure that returns a Result type from a closure that returns an
+/// optional type and Error.
+private func getResultCallback<T>(
+  completion: @escaping (Result<T, Error>) -> Void
+) -> (_: T?, _: Error?) -> Void {
+  return { (value: T?, error: Error?) -> Void in
+    if let value = value {
+      completion(.success(value))
+    } else if let error = error {
+      completion(.failure(error))
+    } else {
+      completion(.failure(NSError(domain: "FirebaseStorageSwift",
+                                  code: -1,
+                                  userInfo: [NSLocalizedDescriptionKey:
+                                    "InternalError - Return type and Error code both nil in " +
+                                    "Storage Result generator"])))
+    }
+  }
+}
+
+public extension StorageReference {
+  func downloadURL(completion: @escaping (Result<URL, Error>) -> Void) {
+    downloadURL(completion: getResultCallback(completion: completion))
+  }
+
+  func getData(maxSize: Int64, completion: @escaping (Result<Data, Error>) -> Void)
+    -> StorageDownloadTask {
+    return getData(maxSize: maxSize, completion: getResultCallback(completion: completion))
+  }
+
+  func getMetadata(completion: @escaping (Result<StorageMetadata, Error>) -> Void) {
+    getMetadata(completion: getResultCallback(completion: completion))
+  }
+
+  func list(withMaxResults maxResults: Int64,
+            pageToken: String,
+            completion: @escaping (Result<StorageListResult, Error>) -> Void) {
+    list(withMaxResults: maxResults,
+         pageToken: pageToken,
+         completion: getResultCallback(completion: completion))
+  }
+
+  func list(withMaxResults maxResults: Int64,
+            completion: @escaping (Result<StorageListResult, Error>) -> Void) {
+    list(withMaxResults: maxResults,
+         completion: getResultCallback(completion: completion))
+  }
+
+  func listAll(completion: @escaping (Result<StorageListResult, Error>) -> Void) {
+    listAll(completion: getResultCallback(completion: completion))
+  }
+
+  func putData(_ uploadData: Data,
+               metadata: StorageMetadata? = nil,
+               completion: @escaping (Result<StorageMetadata, Error>) -> Void)
+    -> StorageUploadTask {
+    return putData(uploadData,
+                   metadata: metadata,
+                   completion: getResultCallback(completion: completion))
+  }
+
+  func putFile(from: URL,
+               metadata: StorageMetadata? = nil,
+               completion: @escaping (Result<StorageMetadata, Error>) -> Void)
+    -> StorageUploadTask {
+    return putFile(from: from,
+                   metadata: metadata,
+                   completion: getResultCallback(completion: completion))
+  }
+
+  func updateMetadata(_ metadata: StorageMetadata,
+                      completion: @escaping (Result<StorageMetadata, Error>) -> Void) {
+    return updateMetadata(metadata, completion: getResultCallback(completion: completion))
+  }
+
+  func write(toFile: URL, completion: @escaping (Result<URL, Error>)
+    -> Void) -> StorageDownloadTask {
+    return write(toFile: toFile, completion: getResultCallback(completion: completion))
+  }
+}