Implement attachment downloading

SignalServiceKit/src/Messages/Attachments/OWSAttachmentDownloads.m

@@ -370,27 +370,8 @@ typedef void (^AttachmentDownloadFailure)(NSError *error);
         });
     };
 
-    if (attachmentPointer.serverId < 100) {
-        OWSLogError(@"Suspicious attachment id: %llu", (unsigned long long)attachmentPointer.serverId);
-    }
-    TSRequest *request = [OWSRequestFactory attachmentRequestWithAttachmentId:attachmentPointer.serverId];
-
-    [self.networkManager makeRequest:request
-        success:^(NSURLSessionDataTask *task, id responseObject) {
-            if (![responseObject isKindOfClass:[NSDictionary class]]) {
-                OWSLogError(@"Failed retrieval of attachment. Response had unexpected format.");
-                NSError *error = OWSErrorMakeUnableToProcessServerResponseError();
-                return markAndHandleFailure(error);
-            }
-            NSString *location = [(NSDictionary *)responseObject objectForKey:@"location"];
-            if (!location) {
-                OWSLogError(@"Failed retrieval of attachment. Response had no location.");
-                NSError *error = OWSErrorMakeUnableToProcessServerResponseError();
-                return markAndHandleFailure(error);
-            }
-
     dispatch_async([OWSDispatch attachmentsQueue], ^{
-                [self downloadFromLocation:location
+        [self downloadFromLocation:attachmentPointer.downloadURL
             job:job
             success:^(NSString *encryptedDataFilePath) {
                 [self decryptAttachmentPath:encryptedDataFilePath
@@ -399,37 +380,9 @@ typedef void (^AttachmentDownloadFailure)(NSError *error);
                                     failure:markAndHandleFailure];
             }
             failure:^(NSURLSessionTask *_Nullable task, NSError *error) {
-                        if (attachmentPointer.serverId < 100) {
-                            // This looks like the symptom of the "frequent 404
-                            // downloading attachments with low server ids".
-                            NSHTTPURLResponse *httpResponse = (NSHTTPURLResponse *)task.response;
-                            NSInteger statusCode = [httpResponse statusCode];
-                            OWSFailDebug(@"%d Failure with suspicious attachment id: %llu, %@",
-                                (int)statusCode,
-                                (unsigned long long)attachmentPointer.serverId,
-                                error);
-                        }
                 markAndHandleFailure(error);
             }];
     });
-        }
-        failure:^(NSURLSessionDataTask *task, NSError *error) {
-            if (!IsNSErrorNetworkFailure(error)) {
-                OWSProdError([OWSAnalyticsEvents errorAttachmentRequestFailed]);
-            }
-            OWSLogError(@"Failed retrieval of attachment with error: %@", error);
-            if (attachmentPointer.serverId < 100) {
-                // This _shouldn't_ be the symptom of the "frequent 404
-                // downloading attachments with low server ids".
-                NSHTTPURLResponse *httpResponse = (NSHTTPURLResponse *)task.response;
-                NSInteger statusCode = [httpResponse statusCode];
-                OWSFailDebug(@"%d Failure with suspicious attachment id: %llu, %@",
-                    (int)statusCode,
-                    (unsigned long long)attachmentPointer.serverId,
-                    error);
-            }
-            return markAndHandleFailure(error);
-        }];
 }
 
 - (void)decryptAttachmentPath:(NSString *)encryptedDataFilePath
@@ -530,7 +483,7 @@ typedef void (^AttachmentDownloadFailure)(NSError *error);
     manager.completionQueue = dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0);
 
     // We want to avoid large downloads from a compromised or buggy service.
-    const long kMaxDownloadSize = 150 * 1024 * 1024;
+    const long kMaxDownloadSize = 12 * 1024 * 1024;
     __block BOOL hasCheckedContentLength = NO;
 
     NSString *tempFilePath =

SignalServiceKit/src/Messages/Attachments/TSAttachmentPointer.m

@@ -167,6 +167,9 @@ NS_ASSUME_NONNULL_BEGIN
                                                                   albumMessageId:albumMessageId
                                                                   attachmentType:attachmentType
                                                                        mediaSize:mediaSize];
+    
+    pointer.downloadURL = attachmentProto.url; // Loki
+    
     return pointer;
 }