Add IOS server push support #143 #144

src/index.js

   // create task ID for receiving progress event
   let taskId = getUUID()
   let options = this || {}
-  let subscription, subscriptionUpload, stateEvent
+  let subscription, subscriptionUpload, stateEvent, partEvent
   let respInfo = {}
 
   let promise = new Promise((resolve, reject) => {
       }
     })
 
+    partEvent = emitter.addListener('RNFetchBlobServerPush', (e) => {
+      if(e.taskId === taskId && promise.onPartData) {
+        promise.onPartData(e.chunk)
+      }
+    })
+
     // When the request body comes from Blob polyfill, we should use special its ref
     // as the request body
     if( body instanceof Blob && body.isRNFetchBlobPolyfill) {
       subscription.remove()
       subscriptionUpload.remove()
       stateEvent.remove()
+      partEvent.remove()
       delete promise['progress']
       delete promise['uploadProgress']
       delete promise['stateChange']
+      delete promise['part']
       delete promise['cancel']
       promise.cancel = () => {}
 
     RNFetchBlob.enableUploadProgressReport(taskId, interval, count)
     return promise
   }
+  promise.part = (fn) => {
+    promise.onPartData = fn
+    return promise
+  }
   promise.stateChange = (fn) => {
     promise.onStateChange = fn
     return promise

src/ios/RNFetchBlobConst.h

 extern NSString *const MSG_EVENT_ERROR;
 
 extern NSString *const EVENT_PROGRESS;
+extern NSString *const EVENT_SERVER_PUSH;
 extern NSString *const EVENT_PROGRESS_UPLOAD;
 extern NSString *const EVENT_STATE_CHANGE;
 

src/ios/RNFetchBlobConst.m

 extern NSString *const CONFIG_EXTRA_BLOB_CTYPE = @"binaryContentTypes";
 
 extern NSString *const EVENT_STATE_CHANGE = @"RNFetchBlobState";
+extern NSString *const EVENT_SERVER_PUSH = @"RNFetchBlobServerPush";
 extern NSString *const EVENT_PROGRESS = @"RNFetchBlobProgress";
 extern NSString *const EVENT_PROGRESS_UPLOAD = @"RNFetchBlobProgress-upload";
 
 // response type
 extern NSString *const RESP_TYPE_BASE64 = @"base64";
 extern NSString *const RESP_TYPE_UTF8 = @"utf8";
-extern NSString *const RESP_TYPE_PATH = @"path";
+extern NSString *const RESP_TYPE_PATH = @"path";

src/ios/RNFetchBlobNetwork.h

 @property (nullable, nonatomic) NSString * taskId;
 @property (nonatomic) int expectedBytes;
 @property (nonatomic) int receivedBytes;
+@property (nonatomic) BOOL isServerPush;
 @property (nullable, nonatomic) NSMutableData * respData;
 @property (strong, nonatomic) RCTResponseSenderBlock callback;
 @property (nullable, nonatomic) RCTBridge * bridge;

src/ios/RNFetchBlobNetwork.m

 @interface RNFetchBlobNetwork ()
 {
     BOOL * respFile;
+    BOOL isNewPart;
+    NSMutableData * partBuffer;
     NSString * destPath;
     NSOutputStream * writeStream;
     long bodyLength;
     {
         NSDictionary *headers = [httpResponse allHeaderFields];
         NSString * respCType = [[RNFetchBlobReqBuilder getHeaderIgnoreCases:@"Content-Type" fromHeaders:headers] lowercaseString];
+        if(self.isServerPush == NO)
+        {
+            self.isServerPush = [[respCType lowercaseString] RNFBContainsString:@"multipart/x-mixed-replace;"];
+        }
+        if(self.isServerPush)
+        {
+            if(partBuffer != nil)
+            {
+                [self.bridge.eventDispatcher
+                 sendDeviceEventWithName:EVENT_SERVER_PUSH
+                 body:@{
+                        @"taskId": taskId,
+                        @"chunk": [partBuffer base64EncodedStringWithOptions:0],
+                        }
+                 ];
+            }
+            partBuffer = [[NSMutableData alloc] init];
+            completionHandler(NSURLSessionResponseAllow);
+            return;
+        }
         if(respCType != nil)
         {
             NSArray * extraBlobCTypes = [options objectForKey:CONFIG_EXTRA_BLOB_CTYPE];
     completionHandler(NSURLSessionResponseAllow);
 }
 
+
 // download progress handler
 - (void) URLSession:(NSURLSession *)session dataTask:(NSURLSessionDataTask *)dataTask didReceiveData:(NSData *)data
 {
+    // For #143 handling multipart/x-mixed-replace response
+    if(self.isServerPush)
+    {
+        [partBuffer appendData:data];
+        return ;
+    }
+    
     NSNumber * received = [NSNumber numberWithLong:[data length]];
     receivedBytes += [received longValue];
     if(respFile == NO)
         session = nil;
 }
 
+
 - (void) URLSession:(NSURLSession *)session task:(NSURLSessionTask *)task didCompleteWithError:(NSError *)error
 {