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IOS File Download Analysis by URL

I use parsing for my chat. When I upload files, I save the URL and send the URL to other users, who can then upload the files through this URL.

Here is my code for downloading files:

+ (void)uploadBlob:(NSData *)blob fileName:(NSString *)fileName type:(NSString *)type {
    if ([self private_checkCloudForbidden]) {
        return;
    }

    if (CHOSEN_SERVER_DATABASE == ServersQuickBlox) {
        if ([Format isThumbnailWithBlobFileName:fileName]) {
            type = @"image";
        }

        NSString *qbContentType = @"";
        if ([type isEqualToString:@"image"]) {
            qbContentType = @"image/jpg";
        }

        [QBContent TUploadFile:blob fileName:fileName contentType:qbContentType isPublic:YES delegate:[CloudDelegate sharedInstance]];


    }

    else if (CHOSEN_SERVER_DATABASE == ServersParse) {

        PFFile *file = [PFFile fileWithName:fileName data:blob];

        [file saveInBackgroundWithBlock:^(BOOL succeeded, NSError *error) {
            if (error){
                NSLog(@"Error: %@", [[error userInfo] objectForKey:@"error"]);
            } else {

                [CloudHandler didUploadBlobWithFileName:file.name blobID:file.url];

            }
        }];

    }
}

and in the CloudHandler didUploadBlobWithFileName method, I will save the file url as blobID. And this is how I upload files via blobID / url when using QuickBlox:

+ (void)downloadWithBlobId: (NSString *)blobID {
    if ([self private_checkCloudForbidden]) {
        return;
    }


    if (CHOSEN_SERVER_DATABASE == ServersQuickBlox) {


        [QBContent TDownloadFileWithBlobID:blobID.integerValue delegate:[CloudDelegate sharedInstance]];

    }

    else if (CHOSEN_SERVER_DATABASE == ServersParse) {

        //TODO: HOW TO DOWNLOAD FILES?

    }

}

I did not find an API to download the file at the url. (this is a little strange if parsing makes url or blobID useless

EDIT:

The reason I don't use attributes like 'file':

1. I can't store 'file' on local database. It has to be the blobID or URL. 

2. when I send a rich message, I can send along the blobID, so that the receiver does not have to fetch the object first before downloading the binary.
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3 answers

You must migrate PFObject instead of url. Like this:

PFObject *object; //the object you have
PFFile *soundFile = object[@"file"];
[soundFile getDataInBackgroundWithBlock:^(NSData *soundData, NSError *error) {
        if (!error) {
            [self saveSoundFileToDocuments:soundData fileName:object[@"fileName"]];
        }
    }
    progressBlock:^(int percentDone) {

    }];

- (void)saveSoundFileToDocuments:(NSData *)soundData fileName:(NSString *)fileName {
    NSString *docsDir;
    NSArray *dirPaths;

    dirPaths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
    docsDir = [dirPaths objectAtIndex:0];
    NSString *databasePath = [[NSString alloc] initWithString: [docsDir stringByAppendingPathComponent:[DataAcesss encryptText:fileName]]];
    [soundData writeToFile:databasePath atomically:YES];
}

.

+5

API, UIKit URL-, , . NSURLConnectionDelegate. , . URL- :

NSURLRequest *theRequest=[NSURLRequest requestWithURL:anUrl
                                          cachePolicy:NSURLRequestUseProtocolCachePolicy
                                      timeoutInterval:CONNECTION_TIMEOUT];
// create the connection with the request
// and start loading the data
urlConnection=[[NSURLConnection alloc] initWithRequest:theRequest delegate:self];
if (urlConnection) {
    // Create the NSMutableData to hold the received data.
    // receivedData is an instance variable declared elsewhere.
    self.receivedData = [NSMutableData data];
} else {
    // Inform the user that the connection failed.
    NSLog(@"Failed to create connection to URL: %@.", anUrl);
}

, , , :

@interface MyClass : NSObject <NSURLConnectionDelegate> {
}
// URLConnection Delegate
- (void)connection:(NSURLConnection *)connection didReceiveResponse:(NSURLResponse *)response;
- (void)connection:(NSURLConnection *)connection didReceiveData:(NSData *)data;
- (void)connection:(NSURLConnection *)connection didFailWithError:(NSError *)error;
- (void)connectionDidFinishLoading:(NSURLConnection *)connection;
- (NSCachedURLResponse *)connection:(NSURLConnection *)connection willCacheResponse:(NSCachedURLResponse *)cachedResponse;

:

- (void)connection:(NSURLConnection *)connection didReceiveResponse:(NSURLResponse *)response
{
    // This method is called when the server has determined that it
    // has enough information to create the NSURLResponse.

    // It can be called multiple times, for example in the case of a
    // redirect, so each time we reset the data.

    // receivedData is an instance variable declared elsewhere.
    [receivedData setLength:0];
}

- (void)connection:(NSURLConnection *)connection didReceiveData:(NSData *)data
{
    // Append the new data to receivedData.
    // receivedData is an instance variable declared elsewhere.
    [receivedData appendData:data];
}

- (void)connection:(NSURLConnection *)connection didFailWithError:(NSError *)error
{
    // Do error handling here
    NSLog(@"Connection failed! Error - %@ %@",
          [error localizedDescription],
          [[error userInfo] objectForKey:NSURLErrorFailingURLStringErrorKey]);
}

- (void)connectionDidFinishLoading:(NSURLConnection *)connection
{
    NSLog(@"Succeeded! Received %d bytes of data",[receivedData length]);
    // Now process the received data accumulated in receivedData.
}

-(NSCachedURLResponse *)connection:(NSURLConnection *)connection willCacheResponse:(NSCachedURLResponse *)cachedResponse
{
    return cachedResponse;
}

.

0

PFFile , SDK iOS. AFNetworking . , - NSData GCD:

dispatch_async(dispatch_get_global_queue(0), ^(){

   NSData* data = [NSData dataWithContentsOfURL:[NSURL URLWithString:file.url]];

   dispath_async(dispatch_get_main_queue(), ^(){

      // do you main UI thread stuff here
   });
});
0

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