(Objective-C) Azure Storage: Download Binary Blob to Memory

See more Azure Cloud Storage Examples

Sample code to download an Azure blob to a Chilkat BinData object, from which the contents can be accessed by your application.

For more information, see https://docs.microsoft.com/en-us/rest/api/storageservices/get-blob

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#import <CkoRest.h>
#import <CkoAuthAzureStorage.h>
#import <CkoBinData.h>

// This example requires the Chilkat API to have been previously unlocked.
// See Global Unlock Sample for sample code.

CkoRest *rest = [[CkoRest alloc] init];

// Connect to the Azure Storage Blob Service
BOOL bTls = YES;
int port = 443;
BOOL bAutoReconnect = YES;
// In this example, the storage account name is "chilkat".
BOOL success = [rest Connect: @"chilkat.blob.core.windows.net" port: [NSNumber numberWithInt: port] tls: bTls autoReconnect: bAutoReconnect];
if (success != YES) {
    NSLog(@"%@",rest.LastErrorText);
    return;
}

// Provide Azure Cloud credentials for the REST call.
CkoAuthAzureStorage *azAuth = [[CkoAuthAzureStorage alloc] init];
azAuth.AccessKey = @"AZURE_ACCESS_KEY";
// The account name used here should match the 1st part of the domain passed in the call to Connect (above).
azAuth.Account = @"chilkat";
azAuth.Scheme = @"SharedKey";
azAuth.Service = @"Blob";
// This causes the "x-ms-version: 2021-08-06" header to be automatically added.
azAuth.XMsVersion = @"2021-08-06";
success = [rest SetAuthAzureStorage: azAuth];

// Note: The application does not need to explicitly set the following
// headers: Content-Length, x-ms-date, Authorization.  These headers
// are automatically set by Chilkat.

// The Azure blob container is "test", the file is "starfish.jpg"
CkoBinData *bd = [[CkoBinData alloc] init];
success = [rest FullRequestNoBodyBd: @"GET" uriPath: @"/test/starfish.jpg" binData: bd];
if (success == NO) {
    // Examine the request/response to see what happened.
    NSLog(@"%@%d",@"response status code = ",[rest.ResponseStatusCode intValue]);
    NSLog(@"%@%@",@"response status text = ",rest.ResponseStatusText);
    NSLog(@"%@%@",@"response header: ",rest.ResponseHeader);
    NSLog(@"%@",@"---");
    NSLog(@"%@%@",@"LastRequestStartLine: ",rest.LastRequestStartLine);
    NSLog(@"%@%@",@"LastRequestHeader: ",rest.LastRequestHeader);
    return;
}

success = [bd WriteFile: @"qa_output/starfish.jpg"];

NSLog(@"%@",@"Success.");