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Rewriting Response Headers

When downloading an object, you can rewrite some HTTP/HTTPS response headers. The following table lists rewritable response headers.

Parameter

Description

Method in OBS iOS SDK

responseContentType

Rewrites Content-Type in HTTP/HTTPS responses.

request.responseContentType

responseContentLanguage

Rewrites Content-Language in HTTP/HTTPS responses.

request.responseContentLanguage

responseExpires

Rewrites Expires in HTTP/HTTPS responses.

request.responseExpires

responseCacheControl

Rewrites Cache-Control in HTTP/HTTPS responses.

request.responseCacheControl

responseContentDisposition

Rewrites Content-Disposition in HTTP/HTTPS responses.

request.responseContentDisposition

responseContentEncoding

Rewrites Content-Encoding in HTTP/HTTPS responses.

request.responseContentEncoding

Sample code:

static OBSClient *client;
NSString *endPoint = @"your-endpoint";
NSString *SK = @"*** Provide your Secret Key ***";
NSString *AK = @"*** Provide your Access Key ***";
    
// Initialize identity authentication.
OBSStaticCredentialProvider *credentialProvider = [[OBSStaticCredentialProvider alloc] initWithAccessKey:AK secretKey:SK];
    
//Initialize service configuration.
OBSServiceConfiguration *conf = [[OBSServiceConfiguration alloc] initWithURLString:endPoint credentialProvider:credentialProvider];
    
// Initialize an instance of OBSClient.
client = [[OBSClient alloc] initWithConfiguration:conf];
    
// Streaming download
OBSGetObjectToDataRequest *request = [[OBSGetObjectToDataRequest alloc]initWithBucketName:@"bucketname" objectKey:@"objectname"];
    
//Rewrite ContentType.
request.responseContentType = @"image/jpeg";
    
    
//Query the download progress.
request.downloadProgressBlock = ^(int64_t bytesWritten, int64_t totalBytesWritten, int64_t totalBytesExpectedToWrite) {
    NSLog(@"%0.1f%%",(float)(totalBytesWritten)*100/(float)totalBytesExpectedToWrite);
};
    
// Receive downloaded data.
__block NSMutableData *objectData = [NSMutableData new];
request.onReceiveDataBlock = ^(NSData *data) {
    [objectData appendData:data];
};
    
// Download result
[client getObject:request completionHandler:^(OBSGetObjectResponse *response, NSError *error){
    NSLog(@"%@",response);
}] ;
Parent topic: Object Download