Delphi DLL

Azure Storage: Lease Container

See more Azure Cloud Storage Examples

Azure Storage Blob Service REST API: Sample code to establishes a lock on a container for delete operations. The lock duration can be 15 to 60 seconds, or can be infinite. Delphi DLL

uses
    Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,
    Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.StdCtrls, Rest, AuthAzureStorage, Crypt2;

...

procedure TForm1.Button1Click(Sender: TObject);
var
success: Boolean;
rest: HCkRest;
bTls: Boolean;
port: Integer;
bAutoReconnect: Boolean;
azAuth: HCkAuthAzureStorage;
crypt: HCkCrypt2;
guid: PWideChar;
responseStr: PWideChar;

begin
success := False;

// Azure Blob Service Example: Lease Container
// See also: https://msdn.microsoft.com/en-us/library/azure/jj159103.aspx

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

rest := CkRest_Create();

// Connect to the Azure Storage Blob Service
bTls := True;
port := 443;
bAutoReconnect := True;
// In this example, the storage account name is "chilkat".
success := CkRest_Connect(rest,'chilkat.blob.core.windows.net',port,bTls,bAutoReconnect);
if (success <> True) then
  begin
    Memo1.Lines.Add(CkRest__lastErrorText(rest));
    Exit;
  end;

// Provide Azure Cloud credentials for the REST call.
azAuth := CkAuthAzureStorage_Create();
CkAuthAzureStorage_putAccessKey(azAuth,'AZURE_ACCESS_KEY');
// The account name used here should match the 1st part of the domain passed in the call to Connect (above).
CkAuthAzureStorage_putAccount(azAuth,'chilkat');
CkAuthAzureStorage_putScheme(azAuth,'SharedKey');
CkAuthAzureStorage_putService(azAuth,'Blob');
// This causes the "x-ms-version: 2021-08-06" header to be automatically added.
CkAuthAzureStorage_putXMsVersion(azAuth,'2021-08-06');
success := CkRest_SetAuthAzureStorage(rest,azAuth);

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

// The lease ID needs to be a GUID.  (UUID and GUID are synonymous)
crypt := CkCrypt2_Create();
guid := CkCrypt2__generateUuid(crypt);
Memo1.Lines.Add('Lease ID: ' + guid);
success := CkRest_AddHeader(rest,'x-ms-lease-id',guid);

// The action can be "acquire", "renew", "change", "release", or "break".
// See https://msdn.microsoft.com/en-us/library/azure/jj159103.aspx
success := CkRest_AddHeader(rest,'x-ms-lease-action','acquire');

// The lease duration..
success := CkRest_AddHeader(rest,'x-ms-lease-duration','15');

// In this example, we are acquiring a lease for the container named "mycontainer".
responseStr := CkRest__fullRequestNoBody(rest,'PUT','/mycontainer?restype=container&comp=lease');
if (CkRest_getLastMethodSuccess(rest) <> True) then
  begin
    Memo1.Lines.Add(CkRest__lastErrorText(rest));
    Exit;
  end;

// When successful, the Azure Storage service will respond with a 200, 201, or 202 response status code,
// with no response body.

// The status code depends on the operation:
//    Acquire: A successful operation returns status code 201 (Created).
//    Renew: A successful operation returns status code 200 (OK).
//    Change: A successful operation returns status code 200 (OK).
//    Release: A successful operation returns status code 200 (OK).
//    Break: A successful operation returns status code 202 (Accepted).

if ((CkRest_getResponseStatusCode(rest) < 200) or (CkRest_getResponseStatusCode(rest) > 202)) then
  begin
    // Examine the request/response to see what happened.
    Memo1.Lines.Add('response status code = ' + IntToStr(CkRest_getResponseStatusCode(rest)));
    Memo1.Lines.Add('response status text = ' + CkRest__responseStatusText(rest));
    Memo1.Lines.Add('response header: ' + CkRest__responseHeader(rest));
    Memo1.Lines.Add('response body (if any): ' + responseStr);
    Memo1.Lines.Add('---');
    Memo1.Lines.Add('LastRequestStartLine: ' + CkRest__lastRequestStartLine(rest));
    Memo1.Lines.Add('LastRequestHeader: ' + CkRest__lastRequestHeader(rest));
    Exit;
  end;

Memo1.Lines.Add('Success: Lease acquired.');

CkRest_Dispose(rest);
CkAuthAzureStorage_Dispose(azAuth);
CkCrypt2_Dispose(crypt);

end;