Fix IOS ALAsset upload issue #45

src/ios/RNFetchBlob.xcodeproj/project.pbxproj

 		A158F4301D0539DB006FFD38 /* RNFetchBlobNetwork.m in Sources */ = {isa = PBXBuildFile; fileRef = A158F42F1D0539DB006FFD38 /* RNFetchBlobNetwork.m */; };
 		A15C30141CD25C330074CB35 /* RNFetchBlob.m in Sources */ = {isa = PBXBuildFile; fileRef = A15C30131CD25C330074CB35 /* RNFetchBlob.m */; };
 		A166D1AA1CE0647A00273590 /* RNFetchBlob.h in Sources */ = {isa = PBXBuildFile; fileRef = A15C30111CD25C330074CB35 /* RNFetchBlob.h */; };
+		A1AAE2991D300E4D0051D11C /* RNFetchBlobReqBuilder.m in Sources */ = {isa = PBXBuildFile; fileRef = A1AAE2981D300E4D0051D11C /* RNFetchBlobReqBuilder.m */; };
 /* End PBXBuildFile section */
 
 /* Begin PBXCopyFilesBuildPhase section */
 		A15C300E1CD25C330074CB35 /* libRNFetchBlob.a */ = {isa = PBXFileReference; explicitFileType = archive.ar; includeInIndex = 0; path = libRNFetchBlob.a; sourceTree = BUILT_PRODUCTS_DIR; };
 		A15C30111CD25C330074CB35 /* RNFetchBlob.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; name = RNFetchBlob.h; path = RNFetchBlob/RNFetchBlob.h; sourceTree = "<group>"; };
 		A15C30131CD25C330074CB35 /* RNFetchBlob.m */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.objc; name = RNFetchBlob.m; path = RNFetchBlob/RNFetchBlob.m; sourceTree = "<group>"; };
+		A1AAE2971D300E3E0051D11C /* RNFetchBlobReqBuilder.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = RNFetchBlobReqBuilder.h; sourceTree = "<group>"; };
+		A1AAE2981D300E4D0051D11C /* RNFetchBlobReqBuilder.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = RNFetchBlobReqBuilder.m; sourceTree = "<group>"; };
 /* End PBXFileReference section */
 
 /* Begin PBXFrameworksBuildPhase section */
 		A15C30051CD25C330074CB35 = {
 			isa = PBXGroup;
 			children = (
+				A1AAE2981D300E4D0051D11C /* RNFetchBlobReqBuilder.m */,
+				A1AAE2971D300E3E0051D11C /* RNFetchBlobReqBuilder.h */,
 				A158F42F1D0539DB006FFD38 /* RNFetchBlobNetwork.m */,
 				A158F42E1D0539CE006FFD38 /* RNFetchBlobNetwork.h */,
 				A158F42C1D0535BB006FFD38 /* RNFetchBlobConst.m */,
 				A158F42D1D0535BB006FFD38 /* RNFetchBlobConst.m in Sources */,
 				A158F4271D052E49006FFD38 /* RNFetchBlobFS.m in Sources */,
 				A158F4301D0539DB006FFD38 /* RNFetchBlobNetwork.m in Sources */,
+				A1AAE2991D300E4D0051D11C /* RNFetchBlobReqBuilder.m in Sources */,
 				A15C30141CD25C330074CB35 /* RNFetchBlob.m in Sources */,
 			);
 			runOnlyForDeploymentPostprocessing = 0;

src/ios/RNFetchBlob/RNFetchBlob.m

 #import "RNFetchBlobFS.h"
 #import "RNFetchBlobNetwork.h"
 #import "RNFetchBlobConst.h"
+#import "RNFetchBlobReqBuilder.h"
 
 
 ////////////////////////////////////////
                   form:(NSArray *)form
                   callback:(RCTResponseSenderBlock)callback)
 {
-    NSString * encodedUrl = [url stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding];
-    // send request
-    NSMutableURLRequest *request = [[NSMutableURLRequest alloc]
-                                    initWithURL:[NSURL
-                                                 URLWithString: encodedUrl]];
     
-    NSMutableDictionary *mheaders = [[NSMutableDictionary alloc] initWithDictionary:[ RNFetchBlobNetwork normalizeHeaders:headers]];
-    
-    
-    NSTimeInterval timeStamp = [[NSDate date] timeIntervalSince1970];
-    NSNumber * timeStampObj = [NSNumber numberWithDouble: timeStamp];
-    
-    // generate boundary
-    NSString * boundary = [NSString stringWithFormat:@"RNFetchBlob%d", timeStampObj];
-    dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{
-        NSMutableData * postData = [[NSMutableData alloc] init];
-        // if method is POST or PUT, convert data string format
-        if([[method lowercaseString] isEqualToString:@"post"] || [[method lowercaseString] isEqualToString:@"put"]) {
-            
-            // combine multipart/form-data body
-            for(id field in form) {
-                NSString * name = [field valueForKey:@"name"];
-                NSString * content = [field valueForKey:@"data"];
-                // field is a text field
-                if([field valueForKey:@"filename"] == nil || content == [NSNull null]) {
-                    [postData appendData:[[NSString stringWithFormat:@"--%@\r\n", boundary] dataUsingEncoding:NSUTF8StringEncoding]];
-                    [postData appendData:[[NSString stringWithFormat:@"Content-Disposition: form-data; name=\"%@\"\r\n", name] dataUsingEncoding:NSUTF8StringEncoding]];
-                    [postData appendData:[[NSString stringWithFormat:@"Content-Type: text/plain\r\n\r\n"] dataUsingEncoding:NSUTF8StringEncoding]];
-                    [postData appendData:[[NSString stringWithFormat:@"%@\r\n", content] dataUsingEncoding:NSUTF8StringEncoding]];
-                }
-                // field contains a file
-                else {
-                    NSMutableData * blobData;
-                    if(content != nil) {
-                        if([content hasPrefix:self.filePathPrefix]) {
-                            NSString * orgPath = [content substringFromIndex:[self.filePathPrefix length]];
-                            orgPath = [RNFetchBlobFS getPathOfAsset:orgPath];
-                            blobData = [[NSData alloc] initWithContentsOfFile:orgPath];
-                        }
-                        else
-                            blobData = [[NSData alloc] initWithBase64EncodedString:content options:0];
-                    }
-                    NSString * filename = [field valueForKey:@"filename"];
-                    [postData appendData:[[NSString stringWithFormat:@"--%@\r\n", boundary] dataUsingEncoding:NSUTF8StringEncoding]];
-                    [postData appendData:[[NSString stringWithFormat:@"Content-Disposition: form-data; name=\"%@\"; filename=\"%@\"\r\n", name, filename] dataUsingEncoding:NSUTF8StringEncoding]];
-                    [postData appendData:[[NSString stringWithFormat:@"Content-Type: application/octet-stream\r\n\r\n"] dataUsingEncoding:NSUTF8StringEncoding]];
-                    [postData appendData:blobData];
-                    [postData appendData:[[NSString stringWithFormat:@"\r\n"] dataUsingEncoding:NSUTF8StringEncoding]];
-                }
-                
-            }
-            
-            // close form data
-            [postData appendData: [[NSString stringWithFormat:@"--%@--\r\n", boundary] dataUsingEncoding:NSUTF8StringEncoding]];
-            [request setHTTPBody:postData];
-            // set content-length
-            [mheaders setValue:[NSString stringWithFormat:@"%d",[postData length]] forKey:@"Content-Length"];
-            [mheaders setValue:[NSString stringWithFormat:@"100-continue",[postData length]] forKey:@"Expect"];
-            // appaned boundary to content-type
-            [mheaders setValue:[NSString stringWithFormat:@"multipart/form-data; charset=utf-8; boundary=%@", boundary] forKey:@"content-type"];
-            
-        }
-        
-        [request setHTTPMethod: method];
-        [request setAllHTTPHeaderFields:mheaders];
-        
-        
+    [RNFetchBlobReqBuilder buildMultipartRequest:options taskId:taskId method:method url:url headers:headers form:form onComplete:^(NSURLRequest *req) {
         // send HTTP request
         RNFetchBlobNetwork * utils = [[RNFetchBlobNetwork alloc] init];
-        [utils sendRequest:options bridge:self.bridge taskId:taskId withRequest:request callback:callback];
+        [utils sendRequest:options bridge:self.bridge taskId:taskId withRequest:req callback:callback];
         utils = nil;
-    });
+    }];
+    
 }
 
 // Fetch blob data request
                   headers:(NSDictionary *)headers
                   body:(NSString *)body callback:(RCTResponseSenderBlock)callback)
 {
-    NSString * encodedUrl = [url stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding];
-    // send request
-    NSMutableURLRequest *request = [[NSMutableURLRequest alloc]
-                                    initWithURL:[NSURL
-                                                 URLWithString: encodedUrl]];
-    
-    NSMutableDictionary *mheaders = [[NSMutableDictionary alloc] initWithDictionary:[RNFetchBlobNetwork normalizeHeaders:headers]];
-    // move heavy task to another thread
-    dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{
-        NSMutableData * blobData;
-        // if method is POST or PUT, convert data string format
-        if([[method lowercaseString] isEqualToString:@"post"] || [[method lowercaseString] isEqualToString:@"put"]) {
-            // generate octet-stream body
-            if(body != nil) {
-                
-                // when body is a string contains file path prefix, try load file from the path
-                if([body hasPrefix:self.filePathPrefix]) {
-                    NSString * orgPath = [body substringFromIndex:[self.filePathPrefix length]];
-                    orgPath = [RNFetchBlobFS getPathOfAsset:orgPath];
-                    [request setHTTPBodyStream: [NSInputStream inputStreamWithFileAtPath:orgPath ]];
-                }
-                // otherwise convert it as BASE64 data string
-                else {
-                    blobData = [[NSData alloc] initWithBase64EncodedString:body options:0];
-                    [request setHTTPBody:blobData];
-                }
-                
-                [mheaders setValue:@"application/octet-stream" forKey:@"content-type"];
-                
-            }
-        }
-        
-        [request setHTTPMethod: method];
-        [request setAllHTTPHeaderFields:mheaders];
-        
+    [RNFetchBlobReqBuilder buildOctetRequest:options taskId:taskId method:method url:url headers:headers body:body onComplete:^(NSURLRequest *req) {
         // send HTTP request
         RNFetchBlobNetwork * utils = [[RNFetchBlobNetwork alloc] init];
-        [utils sendRequest:options bridge:self.bridge taskId:taskId withRequest:request callback:callback];
+        [utils sendRequest:options bridge:self.bridge taskId:taskId withRequest:req callback:callback];
         utils = nil;
-    });
+    }];
+    
 }
 
 RCT_EXPORT_METHOD(createFile:(NSString *)path data:(NSString *)data encoding:(NSString *)encoding callback:(RCTResponseSenderBlock)callback) {
 
 RCT_EXPORT_METHOD(readFile:(NSString *)path encoding:(NSString *)encoding resolver:(RCTPromiseResolveBlock)resolve rejecter:(RCTPromiseRejectBlock)reject {
     
-    [RNFetchBlobFS readFile:path encoding:encoding resolver:resolve rejecter:reject];
+    [RNFetchBlobFS readFile:path encoding:encoding resolver:resolve rejecter:reject onComplete:nil];
 })
 
 RCT_EXPORT_METHOD(readStream:(NSString *)path withEncoding:(NSString *)encoding bufferSize:(int)bufferSize) {
             bufferSize = 4096;
     }
     // read asset stream
-    if([path hasPrefix:@"assets-library://"])
-    {
-        
-    }
-    else
-    {
-        [fileStream readWithPath:path useEncoding:encoding bufferSize:bufferSize];
-    }
+    [fileStream readWithPath:path useEncoding:encoding bufferSize:bufferSize];
 }
 
 RCT_EXPORT_METHOD(getEnvironmentDirs:(RCTResponseSenderBlock) callback) {

src/ios/RNFetchBlobConst.h

 extern NSString *const MSG_EVENT_LOG;
 extern NSString *const MSG_EVENT_WARN;
 extern NSString *const MSG_EVENT_ERROR;
+
 extern NSString *const FILE_PREFIX;
+extern NSString *const ASSET_PREFIX;
+extern NSString *const AL_PREFIX;
 
 // config
 extern NSString *const CONFIG_USE_TEMP;

src/ios/RNFetchBlobConst.m

 #import "RNFetchBlobConst.h"
 
 extern NSString *const FILE_PREFIX = @"RNFetchBlob-file://";
+extern NSString *const ASSET_PREFIX = @"bundle-assets://";
+extern NSString *const AL_PREFIX = @"assets-library://";
+
+
 
 // fetch configs
 extern NSString *const CONFIG_USE_TEMP = @"fileCache";

src/ios/RNFetchBlobFS.h

 
 #import <Foundation/Foundation.h>
 #import "RCTBridgeModule.h"
+@import AssetsLibrary;
 
 @interface RNFetchBlobFS : NSObject <NSStreamDelegate>  {
     NSOutputStream * outStream;
 + (NSString *) getCacheDir;
 + (NSString *) getDocumentDir;
 + (NSString *) getTempPath:(NSString*)taskId withExtension:(NSString *)ext;
++ (NSString *) getPathOfAsset:(NSString *)assetURI;
++ (void) getPathFromUri:(NSString *)uri completionHandler:(void(^)(NSString * path, ALAssetRepresentation *asset)) onComplete;
 
 // fs methods
 + (RNFetchBlobFS *) getFileStreams;
 + (BOOL) exists:(NSString *) path;
 + (void) writeFileArray:(NSString *)path data:(NSArray *)data append:(BOOL)append resolver:(RCTPromiseResolveBlock)resolve rejecter:(RCTPromiseRejectBlock)reject;
 + (void) writeFile:(NSString *)path encoding:(NSString *)encoding data:(NSString *)data append:(BOOL)append resolver:(RCTPromiseResolveBlock)resolve rejecter:(RCTPromiseRejectBlock)reject;
-+ (void) readFile:(NSString *)path encoding:(NSString *)encoding resolver:(RCTPromiseResolveBlock)resolve rejecter:(RCTPromiseRejectBlock)reject;
++ (void) readFile:(NSString *)path encoding:(NSString *)encoding resolver:(RCTPromiseResolveBlock)resolve rejecter:(RCTPromiseRejectBlock)reject onComplete:(void (^)(NSData * content))onComplete;
 + (void) readAssetFile:(NSData *)assetUrl completionBlock:(void(^)(NSData * content))completionBlock failBlock:(void(^)(NSError * err))failBlock;
-+ (NSString *) getPathOfAsset:(NSString *)assetURI;
 
 // constructor
 - (id) init;

src/ios/RNFetchBlobFS.m

 #import "RNFetchBlobFS.h"
 #import "RNFetchBlobConst.h"
 @import AssetsLibrary;
-@import Photos;
+
 
 NSMutableDictionary *fileStreams = nil;
 
 +(NSString *) getPathOfAsset:(NSString *)assetURI
 {
     // get file path of an app asset
-    if([assetURI hasPrefix:@"bundle-assets://"])
+    if([assetURI hasPrefix:ASSET_PREFIX])
     {
-        assetURI = [assetURI stringByReplacingOccurrencesOfString:@"bundle-assets://" withString:@""];
+        assetURI = [assetURI stringByReplacingOccurrencesOfString:ASSET_PREFIX withString:@""];
         assetURI = [[NSBundle mainBundle] pathForResource: [assetURI stringByDeletingPathExtension]
                                                ofType: [assetURI pathExtension]];
     }
     return tempPath;
 }
 
-- (void) startAssetReadStream:(NSData *)assetUrl
+- (void) startAssetReadStream:(NSString *)assetUrl
 {
     ALAssetsLibraryAssetForURLResultBlock resultblock = ^(ALAsset *myasset)
     {
     }
 }
 
-// read system asset file
-+ (void) readAssetFile:(NSData *)assetUrl completionBlock:(void(^)(NSData * content))completionBlock failBlock:(void(^)(NSError * err))failBlock
-{
-    
-    ALAssetsLibraryAssetForURLResultBlock resultblock = ^(ALAsset *myasset)
-    {
-        ALAssetRepresentation *rep = [myasset defaultRepresentation];
-        Byte *buffer = (Byte*)malloc(rep.size);
-        NSUInteger buffered = [rep getBytes:buffer fromOffset:0.0 length:rep.size error:nil];
-        NSData *data = [NSData dataWithBytesNoCopy:buffer length:buffered freeWhenDone:YES];
-        completionBlock(data);
-    };
-    
-    ALAssetsLibraryAccessFailureBlock failureblock  = ^(NSError *error)
-    {
-        failBlock(error);
-    };
-    
-    if(assetUrl && [assetUrl length])
-    {
-        NSURL *asseturl = [NSURL URLWithString:assetUrl];
-        ALAssetsLibrary* assetslibrary = [[ALAssetsLibrary alloc] init];
-        [assetslibrary assetForURL:asseturl
-                       resultBlock:resultblock
-                      failureBlock:failureblock];
-    }
-}
-
 + (void) writeFile:(NSString *)path encoding:(NSString *)encoding data:(NSString *)data append:(BOOL)append resolver:(RCTPromiseResolveBlock)resolve rejecter:(RCTPromiseRejectBlock)reject {
     @try {
         NSFileManager * fm = [NSFileManager defaultManager];
     }
 }
 
-+ (void) readFile:(NSString *)path encoding:(NSString *)encoding resolver:(RCTPromiseResolveBlock)resolve rejecter:(RCTPromiseRejectBlock)reject {
++ (void) readFile:(NSString *)path encoding:(NSString *)encoding
+         resolver:(RCTPromiseResolveBlock)resolve
+         rejecter:(RCTPromiseRejectBlock)reject
+       onComplete:(void (^)(NSData * content))onComplete
+{
     @try
     {
-        // before start reading file, we have to check if the `path` contains any special prefix
-        // if the `path` begins with the following prefix then it will need special handling.
-        //      "assets-library://" this kind of path usually comes from camera roll, should use it's own readFile implementation
-        //      "bundle-assets://" this means an asset inside app bundle, usually we only have to convert it into normal file path
-        if([path hasPrefix:@"assets-library://"])
-        {
-            [[self class] readAssetFile:path completionBlock:^(NSData * content)
+        [[self class] getPathFromUri:path completionHandler:^(NSString *path, ALAssetRepresentation *asset) {
+            NSData * fileContent;
+            NSError * err;
+            if(asset != nil)
+            {
+                Byte * buffer = malloc(asset.size);
+                [asset getBytes:buffer fromOffset:0 length:asset.size error:&err];
+                if(err != nil)
+                {
+                    reject(@"RNFetchBlobFS readFile error", @"failed to read asset", [err localizedDescription]);
+                    return;
+                }
+                fileContent = [NSData dataWithBytes:buffer length:asset.size];
+                if(onComplete != nil)
+                    onComplete(fileContent);
+                free(buffer);
+            }
+            else
             {
-                if([[encoding lowercaseString] isEqualToString:@"utf8"]) {
-                    resolve([[NSString alloc] initWithData:content encoding:NSUTF8StringEncoding]);
+                BOOL exists = [[NSFileManager defaultManager] fileExistsAtPath:path];
+                if(!exists) {
+                    reject(@"RNFetchBlobFS readFile error", @"file not exists", path);
+                    return;
                 }
-                else if ([[encoding lowercaseString] isEqualToString:@"base64"]) {
-                    resolve([content base64EncodedStringWithOptions:0]);
+                fileContent = [NSData dataWithContentsOfFile:path];
+            }
+            
+            if([[encoding lowercaseString] isEqualToString:@"utf8"]) {
+                if(resolve != nil)
+                    resolve([[NSString alloc] initWithData:fileContent encoding:NSUTF8StringEncoding]);
+            }
+            else if ([[encoding lowercaseString] isEqualToString:@"base64"]) {
+                if(resolve != nil)
+                    resolve([fileContent base64EncodedStringWithOptions:0]);
+            }
+            else if ([[encoding lowercaseString] isEqualToString:@"ascii"]) {
+                NSMutableArray * resultArray = [NSMutableArray array];
+                char * bytes = [fileContent bytes];
+                for(int i=0;i<[fileContent length];i++) {
+                    [resultArray addObject:[NSNumber numberWithChar:bytes[i]]];
                 }
-                else if ([[encoding lowercaseString] isEqualToString:@"ascii"]) {
-                    NSMutableArray * resultArray = [NSMutableArray array];
-                    char * bytes = [content bytes];
-                    for(int i=0;i<[content length];i++) {
-                        [resultArray addObject:[NSNumber numberWithChar:bytes[i]]];
-                    }
+                if(resolve != nil)
                     resolve(resultArray);
-                }
-            } failBlock:^(NSError *err) {
-                @throw @"RNFetchBlobFS readFile error", @"failed to read asset", path;
-            }];
-            return ;
-        }
-        
-        // normalize the file path
-        path = [[self class]getPathOfAsset:path];
-        
-        NSFileManager * fm = [NSFileManager defaultManager];
-        NSError *err = nil;
-        BOOL exists = [fm fileExistsAtPath:path];
-        if(!exists) {
-            @throw @"RNFetchBlobFS readFile error", @"file not exists", path;
-            return;
-        }
-        if([[encoding lowercaseString] isEqualToString:@"utf8"]) {
-            NSString * utf8Result = [NSString stringWithContentsOfFile:path encoding:NSUTF8StringEncoding error:&err];
-            resolve(utf8Result);
-        }
-        else if ([[encoding lowercaseString] isEqualToString:@"base64"]) {
-            NSData * fileData = [NSData dataWithContentsOfFile:path];
-            resolve([fileData base64EncodedStringWithOptions:0]);
-        }
-        else if ([[encoding lowercaseString] isEqualToString:@"ascii"]) {
-            NSData * resultData = [NSData dataWithContentsOfFile:path];
-            NSMutableArray * resultArray = [NSMutableArray array];
-            char * bytes = [resultData bytes];
-            for(int i=0;i<[resultData length];i++) {
-                [resultArray addObject:[NSNumber numberWithChar:bytes[i]]];
             }
-            resolve(resultArray);
-        }
-
+        }];
     }
     @catch(NSException * e)
     {
+        if(reject != nil)
         reject(@"RNFetchBlobFS readFile error", @"error", [e description]);
     }
 }
     self.path = path;
     self.bufferSize = bufferSize;
     
-    if([path hasPrefix:@"assets-library://"])
+    if([path hasPrefix:AL_PREFIX])
     {
-     
+        [self startAssetReadStream:path];
         return;
     }
     
 
 }
 
++ (void) getPathFromUri:(NSString *)uri completionHandler:(void(^)(NSString * path, ALAssetRepresentation *asset)) onComplete
+{
+    if([uri hasPrefix:AL_PREFIX])
+    {
+        NSURL *asseturl = [NSURL URLWithString:uri];
+        ALAssetsLibrary* assetslibrary = [[ALAssetsLibrary alloc] init];
+        [assetslibrary assetForURL:asseturl
+                       resultBlock:^(ALAsset *asset) {
+                           onComplete(nil, [asset defaultRepresentation]);
+                       }
+                      failureBlock:^(NSError *error) {
+                          onComplete(nil, nil);
+                      }];
+    }
+    else
+    {
+        onComplete([[self class] getPathOfAsset:uri], nil);
+    }
+}
+
 @end

src/ios/RNFetchBlobNetwork.h

 
 #import <Foundation/Foundation.h>
 #import "RCTBridgeModule.h"
+#import "RNFetchBlobFS.h"
 
 typedef void(^CompletionHander)(NSURL * _Nullable location, NSURLResponse * _Nullable response, NSError * _Nullable error);
 typedef void(^DataTaskCompletionHander) (NSData * _Nullable resp, NSURLResponse * _Nullable response, NSError * _Nullable error);

src/ios/RNFetchBlobReqBuilder.h

+//
+//  RNFetchBlobReqBuilder.h
+//  RNFetchBlob
+//
+//  Created by Ben Hsieh on 2016/7/9.
+//  Copyright © 2016年 wkh237. All rights reserved.
+//
+
+#ifndef RNFetchBlobReqBuilder_h
+#define RNFetchBlobReqBuilder_h
+
+#import <Foundation/Foundation.h>
+
+@interface RNFetchBlobReqBuilder : NSObject;
+
++(void) buildMultipartRequest:(NSDictionary *)options
+                       taskId:(NSString *)taskId
+                       method:(NSString *)method
+                          url:(NSString *)url
+                      headers:(NSDictionary *)headers
+                         form:(NSArray *)form
+                   onComplete:(void(^)(NSURLRequest * req))onComplete;
+
++(void) buildOctetRequest:(NSDictionary *)options
+                   taskId:(NSString *)taskId
+                   method:(NSString *)method
+                      url:(NSString *)url
+                  headers:(NSDictionary *)headers
+                     body:(NSString *)body
+               onComplete:(void(^)(NSURLRequest * req))onComplete;
+
+@end
+
+#endif /* RNFetchBlobReqBuilder_h */

src/ios/RNFetchBlobReqBuilder.m

+//
+//  RNFetchBlobReqBuilder.m
+//  RNFetchBlob
+//
+//  Created by Ben Hsieh on 2016/7/9.
+//  Copyright © 2016年 wkh237. All rights reserved.
+//
+
+#import <Foundation/Foundation.h>
+#import "RNFetchBlobReqBuilder.h"
+#import "RNFetchBlobNetwork.h"
+#import "RNFetchBlobConst.h"
+#import "RNFetchBlobFS.h"
+
+@interface RNFetchBlobReqBuilder()
+{
+    
+}
+@end
+
+@implementation RNFetchBlobReqBuilder
+
+
+// Fetch blob data request
++(void) buildMultipartRequest:(NSDictionary *)options
+                       taskId:(NSString *)taskId
+                       method:(NSString *)method
+                          url:(NSString *)url
+                      headers:(NSDictionary *)headers
+                         form:(NSArray *)form
+                   onComplete:(void(^)(NSURLRequest * req))onComplete
+{
+    NSString * encodedUrl = [url stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding];
+    // send request
+    NSMutableURLRequest *request = [[NSMutableURLRequest alloc] initWithURL:[NSURL URLWithString: encodedUrl]];
+    NSMutableDictionary *mheaders = [[NSMutableDictionary alloc] initWithDictionary:[RNFetchBlobNetwork normalizeHeaders:headers]];
+    NSTimeInterval timeStamp = [[NSDate date] timeIntervalSince1970];
+    NSNumber * timeStampObj = [NSNumber numberWithDouble: timeStamp];
+    
+    // generate boundary
+    NSString * boundary = [NSString stringWithFormat:@"RNFetchBlob%d", timeStampObj];
+    dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{
+        NSMutableData * postData = [[NSMutableData alloc] init];
+        // combine multipart/form-data body
+        [[self class] buildFormBody:form boundary:boundary onComplete:^(NSData *formData) {
+            if(formData != nil) {
+                [postData appendData:formData];
+                // close form data
+                [postData appendData: [[NSString stringWithFormat:@"--%@--\r\n", boundary] dataUsingEncoding:NSUTF8StringEncoding]];
+                [request setHTTPBody:postData];
+            }
+            // set content-length
+            [mheaders setValue:[NSString stringWithFormat:@"%d",[postData length]] forKey:@"Content-Length"];
+            [mheaders setValue:[NSString stringWithFormat:@"100-continue",[postData length]] forKey:@"Expect"];
+            // appaned boundary to content-type
+            [mheaders setValue:[NSString stringWithFormat:@"multipart/form-data; charset=utf-8; boundary=%@", boundary] forKey:@"content-type"];
+            [request setHTTPMethod: method];
+            [request setAllHTTPHeaderFields:mheaders];
+            onComplete(request);
+        }];
+        
+    });
+}
+
+// Fetch blob data request
++(void) buildOctetRequest:(NSDictionary *)options
+                   taskId:(NSString *)taskId
+                   method:(NSString *)method
+                      url:(NSString *)url
+                  headers:(NSDictionary *)headers
+                     body:(NSString *)body
+               onComplete:(void(^)(NSURLRequest * req))onComplete
+{
+    NSString * encodedUrl = [url stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding];
+    // send request
+    NSMutableURLRequest *request = [[NSMutableURLRequest alloc]
+                                    initWithURL:[NSURL
+                                                 URLWithString: encodedUrl]];
+    
+    NSMutableDictionary *mheaders = [[NSMutableDictionary alloc] initWithDictionary:[RNFetchBlobNetwork normalizeHeaders:headers]];
+    // move heavy task to another thread
+    dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{
+        NSMutableData * blobData;
+        // if method is POST or PUT, convert data string format
+        if([[method lowercaseString] isEqualToString:@"post"] || [[method lowercaseString] isEqualToString:@"put"]) {
+            // generate octet-stream body
+            if(body != nil) {
+                
+                // when body is a string contains file path prefix, try load file from the path
+                if([body hasPrefix:FILE_PREFIX]) {
+                    NSString * orgPath = [body substringFromIndex:[FILE_PREFIX length]];
+                    orgPath = [RNFetchBlobFS getPathOfAsset:orgPath];
+                    if([orgPath hasPrefix:AL_PREFIX])
+                    {
+                        [RNFetchBlobFS readFile:orgPath encoding:@"utf8" resolver:nil rejecter:nil onComplete:^(NSData *content) {
+                            [request setHTTPBody:content];
+                            [mheaders setValue:@"application/octet-stream" forKey:@"content-type"];
+                            [request setHTTPMethod: method];
+                            [request setAllHTTPHeaderFields:mheaders];
+                            onComplete(request);
+                        }];
+                        return;
+                    }
+                    [request setHTTPBodyStream: [NSInputStream inputStreamWithFileAtPath:orgPath ]];
+                }
+                // otherwise convert it as BASE64 data string
+                else {
+                    blobData = [[NSData alloc] initWithBase64EncodedString:body options:0];
+                    [request setHTTPBody:blobData];
+                }
+                
+                [mheaders setValue:@"application/octet-stream" forKey:@"content-type"];
+                
+            }
+        }
+        
+        [request setHTTPMethod: method];
+        [request setAllHTTPHeaderFields:mheaders];
+        
+        onComplete(request);
+    });
+}
+
++(void) buildFormBody:(NSArray *)form boundary:(NSString *)boundary onComplete:(void(^)(NSData * formData))onComplete
+{
+    NSMutableData * formData = [[NSMutableData alloc] init];
+    if(form == nil)
+        onComplete(nil);
+    else
+    {
+        __block int i = 0;
+        __block int count = [form count];
+        void __block (^getFieldData)(id field) = ^(id field)
+        {
+            NSString * name = [field valueForKey:@"name"];
+            NSString * content = [field valueForKey:@"data"];
+            // field is a text field
+            if([field valueForKey:@"filename"] == nil || content == [NSNull null]) {
+                [formData appendData:[[NSString stringWithFormat:@"--%@\r\n", boundary] dataUsingEncoding:NSUTF8StringEncoding]];
+                [formData appendData:[[NSString stringWithFormat:@"Content-Disposition: form-data; name=\"%@\"\r\n", name] dataUsingEncoding:NSUTF8StringEncoding]];
+                [formData appendData:[[NSString stringWithFormat:@"Content-Type: text/plain\r\n\r\n"] dataUsingEncoding:NSUTF8StringEncoding]];
+                [formData appendData:[[NSString stringWithFormat:@"%@\r\n", content] dataUsingEncoding:NSUTF8StringEncoding]];
+            }
+            // field contains a file
+            else {
+                NSMutableData * blobData;
+                if(content != nil)
+                {
+                    // append data from file asynchronously
+                    if([content hasPrefix:FILE_PREFIX])
+                    {
+                        NSString * orgPath = [content substringFromIndex:[FILE_PREFIX length]];
+                        orgPath = [RNFetchBlobFS getPathOfAsset:orgPath];
+                        [RNFetchBlobFS readFile:orgPath encoding:@"utf8" resolver:nil rejecter:nil onComplete:^(NSData *content) {
+                            NSString * filename = [field valueForKey:@"filename"];
+                            [formData appendData:[[NSString stringWithFormat:@"--%@\r\n", boundary] dataUsingEncoding:NSUTF8StringEncoding]];
+                            [formData appendData:[[NSString stringWithFormat:@"Content-Disposition: form-data; name=\"%@\"; filename=\"%@\"\r\n", name, filename] dataUsingEncoding:NSUTF8StringEncoding]];
+                            [formData appendData:[[NSString stringWithFormat:@"Content-Type: application/octet-stream\r\n\r\n"] dataUsingEncoding:NSUTF8StringEncoding]];
+                            [formData appendData:content];
+                            [formData appendData:[[NSString stringWithFormat:@"\r\n"] dataUsingEncoding:NSUTF8StringEncoding]];
+                            i++;
+                            if(i < count)
+                            {
+                                getFieldData([form objectAtIndex:i]);
+                            }
+                            else
+                                onComplete(formData);
+                        }];
+                        return ;
+                    }
+                    else
+                        blobData = [[NSData alloc] initWithBase64EncodedString:content options:0];
+                }
+                NSString * filename = [field valueForKey:@"filename"];
+                [formData appendData:[[NSString stringWithFormat:@"--%@\r\n", boundary] dataUsingEncoding:NSUTF8StringEncoding]];
+                [formData appendData:[[NSString stringWithFormat:@"Content-Disposition: form-data; name=\"%@\"; filename=\"%@\"\r\n", name, filename] dataUsingEncoding:NSUTF8StringEncoding]];
+                [formData appendData:[[NSString stringWithFormat:@"Content-Type: application/octet-stream\r\n\r\n"] dataUsingEncoding:NSUTF8StringEncoding]];
+                [formData appendData:blobData];
+                [formData appendData:[[NSString stringWithFormat:@"\r\n"] dataUsingEncoding:NSUTF8StringEncoding]];
+            }
+            i++;
+            if(i < count)
+            {
+                getFieldData([form objectAtIndex:i]);
+            }
+            else
+                onComplete(formData);
+            
+        };
+        getFieldData([form objectAtIndex:i]);
+    }
+}
+
+
+@end