1 files changed, 117 insertions, 0 deletions
diff --git a/Firebase/Storage/FIRStorageGetDownloadURLTask.m b/Firebase/Storage/FIRStorageGetDownloadURLTask.m
new file mode 100644
index 0000000..02d202e
--- /dev/null
+++ b/Firebase/Storage/FIRStorageGetDownloadURLTask.m
@@ -0,0 +1,117 @@
+// Copyright 2018 Google
+//
+// 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 "FIRStorageGetDownloadURLTask.h"
+
+#import "FIRStorageTask_Private.h"
+
+@implementation FIRStorageGetDownloadURLTask {
+ @private
+  FIRStorageVoidURLError _completion;
+}
+
+@synthesize fetcher = _fetcher;
+@synthesize fetcherCompletion = _fetcherCompletion;
+
+- (instancetype)initWithReference:(FIRStorageReference *)reference
+                   fetcherService:(GTMSessionFetcherService *)service
+                       completion:(FIRStorageVoidURLError)completion {
+  self = [super initWithReference:reference fetcherService:service];
+  if (self) {
+    _completion = [completion copy];
+  }
+  return self;
+}
+
+- (void)dealloc {
+  [_fetcher stopFetching];
+}
+
++ (NSURL *)downloadURLFromMetadataDictionary:(NSDictionary *)dictionary {
+  NSString *downloadTokens = dictionary[kFIRStorageMetadataDownloadTokens];
+
+  if (downloadTokens && downloadTokens.length > 0) {
+    NSArray<NSString *> *downloadTokenArray = [downloadTokens componentsSeparatedByString:@","];
+    NSString *bucket = dictionary[kFIRStorageMetadataBucket];
+    NSString *path = dictionary[kFIRStorageMetadataName];
+    NSString *fullPath = [NSString stringWithFormat:kFIRStorageFullPathFormat, bucket,
+                                                    [FIRStorageUtils GCSEscapedString:path]];
+
+    NSURLComponents *components = [[NSURLComponents alloc] init];
+    components.scheme = kFIRStorageScheme;
+    components.host = kFIRStorageHost;
+    components.percentEncodedPath = fullPath;
+
+    // The backend can return an arbitrary number of download tokens, but we only expose the first
+    // token via the download URL.
+    NSURLQueryItem *altItem = [[NSURLQueryItem alloc] initWithName:@"alt" value:@"media"];
+    NSURLQueryItem *tokenItem =
+        [[NSURLQueryItem alloc] initWithName:@"token" value:downloadTokenArray[0]];
+    components.queryItems = @[ altItem, tokenItem ];
+
+    return [components URL];
+  }
+
+  return nil;
+}
+
+- (void)enqueue {
+  NSMutableURLRequest *request = [self.baseRequest mutableCopy];
+  request.HTTPMethod = @"GET";
+  request.timeoutInterval = self.reference.storage.maxOperationRetryTime;
+
+  FIRStorageVoidURLError callback = _completion;
+  _completion = nil;
+
+  GTMSessionFetcher *fetcher = [self.fetcherService fetcherWithRequest:request];
+  _fetcher = fetcher;
+  fetcher.comment = @"GetDownloadURLTask";
+
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Warc-retain-cycles"
+  _fetcherCompletion = ^(NSData *data, NSError *error) {
+    NSURL *downloadURL;
+    if (error) {
+      if (!self.error) {
+        self.error = [FIRStorageErrors errorWithServerError:error reference:self.reference];
+      }
+    } else {
+      NSDictionary *responseDictionary = [NSDictionary frs_dictionaryFromJSONData:data];
+      if (responseDictionary != nil) {
+        downloadURL =
+            [FIRStorageGetDownloadURLTask downloadURLFromMetadataDictionary:responseDictionary];
+        if (!downloadURL) {
+          self.error =
+              [FIRStorageErrors errorWithCustomMessage:@"Failed to retrieve a download URL."];
+        }
+      } else {
+        self.error = [FIRStorageErrors errorWithInvalidRequest:data];
+      }
+    }
+
+    if (callback) {
+      callback(downloadURL, self.error);
+    }
+
+    self->_fetcherCompletion = nil;
+  };
+#pragma clang diagnostic pop
+
+  __weak FIRStorageGetDownloadURLTask *weakSelf = self;
+  [fetcher beginFetchWithCompletionHandler:^(NSData *data, NSError *error) {
+    weakSelf.fetcherCompletion(data, error);
+  }];
+}
+
+@end