Objective-C

How to Generate an Azure Storage Account Shared Access Signature (SAS)

See more Azure Cloud Storage Examples

Shows how to generate a Shared Access Signature (SAS) for an Azure Storage Account.

Note: This example requires Chilkat v9.5.0.65 or greater.

Objective-C

#import <CkoAuthAzureSAS.h>
#import <CkoDateTime.h>
#import <NSString.h>
#import <CkoFileAccess.h>

// Note: Requires Chilkat v9.5.0.65 or greater.

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

// --------------------------------------------------------------------------
// Create a Shared Access Signature (SAS) token for an Azure Storage Account.
// --------------------------------------------------------------------------

// See https://docs.microsoft.com/en-us/rest/api/storageservices/fileservices/constructing-an-account-sas 
// for details regarding the Azure Storage Account SAS fields.

CkoAuthAzureSAS *authSas = [[CkoAuthAzureSAS alloc] init];
authSas.AccessKey = @"AZURE_ACCESS_KEY";

// Specify the format of the string to sign.
// Each comma character in the following string represents a LF ("\n") character.
// The names specified in the StringToSign are replaced with the values specified
// in the subsequent calls to SetTokenParam and SetNonTokenParam,.

// Note: The trailing comma in the StringToSign is intentional and important. This indicates that the 
// string to sign will end with a "\n".

// Also note: The names in the StringToSign are case sensitive.  The names
// specified in the 1st argument in the calls to SetNonTokenParam and SetTokenParam should
// match a name listed in StringToSign. 
authSas.StringToSign = @"accountname,signedpermissions,signedservice,signedresourcetype,signedstart,signedexpiry,signedIP,signedProtocol,signedversion,";

//  The account name is "chilkat".  Use your own account name instead of "chilkat".
//  Also use your own container name instead of "mycontainer".
[authSas SetNonTokenParam: @"accountname" value: @"chilkat"];

[authSas SetTokenParam: @"signedpermissions" authParamName: @"sp" value: @"rwdlacup"];
[authSas SetTokenParam: @"signedservice" authParamName: @"ss" value: @"bfqt"];
[authSas SetTokenParam: @"signedresourcetype" authParamName: @"srt" value: @"sco"];

CkoDateTime *dt = [[CkoDateTime alloc] init];
[dt SetFromCurrentSystemTime];
[authSas SetTokenParam: @"signedstart" authParamName: @"st" value: [dt GetAsIso8601: @"YYYY-MM-DDThh:mmTZD" bLocal: NO]];

// This SAS token will be valid for 30 days.
[dt AddDays: [NSNumber numberWithInt: 30]];
[authSas SetTokenParam: @"signedexpiry" authParamName: @"se" value: [dt GetAsIso8601: @"YYYY-MM-DDThh:mmTZD" bLocal: NO]];

[authSas SetTokenParam: @"signedProtocol" authParamName: @"spr" value: @"https"];

//  Specifiy values and query param names for each field.
//  If a field is not specified, then an empty string will be used for its value.
[authSas SetTokenParam: @"signedversion" authParamName: @"sv" value: @"2015-04-05"];

// Note that we did not call SetTokenParam for "signedIP".  For any omitted fields
// the value will default to the empty string.

// Generate the SAS token.
NSString *sasToken = [authSas GenerateToken];
if (authSas.LastMethodSuccess != YES) {
    NSLog(@"%@",authSas.LastErrorText);
    return;
}

NSLog(@"%@%@",@"SAS token: ",sasToken);

// Save the SAS token to a file.
// We can then use this pre-generated token for future Azure Storage Account operations.
CkoFileAccess *fac = [[CkoFileAccess alloc] init];
[fac WriteEntireTextFile: @"qa_data/tokens/azureStorageAccountSas.txt" fileData: sasToken charset: @"utf-8" includePreamble: NO];