Pascal (Lazarus/Delphi)

DynamoDB - DeleteTable

See more Amazon DynamoDB Examples

The DeleteTable operation deletes a table and all of its items. After a DeleteTable request, the specified table is in the DELETING state until DynamoDB completes the deletion. Pascal (Lazarus/Delphi)

program ChilkatDemo;

// Demonstrates using the Chilkat Pascal wrapper via the C bridge DLL.
// Builds as a console application under Lazarus (FPC) or Delphi.

{$IFDEF FPC}
  {$MODE DELPHI}
{$ENDIF}
{$APPTYPE CONSOLE}

uses
  {$IFDEF UNIX}
  cthreads,
  {$ENDIF}
  SysUtils,
  CkDllLoader,
  Chilkat.AuthAws,
  Chilkat.Rest,
  Chilkat.JsonObject,
  Chilkat.StringBuilder;

// ---------------------------------------------------------------------------

procedure RunDemo;
var
  success: Boolean;
  rest: TRest;
  authAws: TAuthAws;
  bTls: Boolean;
  port: Integer;
  bAutoReconnect: Boolean;
  json: TJsonObject;
  sbRequestBody: TStringBuilder;
  sbResponseBody: TStringBuilder;
  respStatusCode: Integer;
  jsonResponse: TJsonObject;
  TableDescriptionTableArn: string;
  TableDescriptionItemCount: Integer;
  TableDescriptionProvisionedThroughputNumberOfDecreasesToday: Integer;
  TableDescriptionProvisionedThroughputReadCapacityUnits: Integer;
  TableDescriptionProvisionedThroughputWriteCapacityUnits: Integer;
  TableDescriptionTableName: string;
  TableDescriptionTableSizeBytes: Integer;
  TableDescriptionTableStatus: string;

begin
  success := False;

  rest := TRest.Create;

  //  Implements the following CURL command:

  //  curl -X POST https://dynamodb.us-west-2.amazonaws.com/ \
  //    -H "Accept-Encoding: identity" \
  //    -H "Content-Type: application/x-amz-json-1.0" \
  //    -H "Authorization: AWS4-HMAC-SHA256 Credential=<Credential>, SignedHeaders=<Headers>, Signature=<Signature>" \
  //    -H "X-Amz-Date: <Date>" \
  //    -H "X-Amz-Target: DynamoDB_20120810.DeleteTable" \
  //    -d '{
  //      "TableName": "Thread"
  //  }'

  //  Use the following online tool to generate REST code from a CURL command
  //  Convert a cURL Command to REST Source Code

  authAws := TAuthAws.Create;
  authAws.AccessKey := 'AWS_ACCESS_KEY';
  authAws.SecretKey := 'AWS_SECRET_KEY';
  //  Don't forget to change the region to your particular region. (Also make the same change in the call to Connect below.)
  authAws.Region := 'us-west-2';
  authAws.ServiceName := 'dynamodb';
  //  SetAuthAws causes Chilkat to automatically add the following headers: Authorization, X-Amz-Date
  rest.SetAuthAws(authAws);

  //  URL: https://dynamodb.us-west-2.amazonaws.com/
  bTls := True;
  port := 443;
  bAutoReconnect := True;
  //  Don't forget to change the region domain (us-west-2.amazonaws.com) to your particular region.
  success := rest.Connect('dynamodb.us-west-2.amazonaws.com',port,bTls,bAutoReconnect);
  if (success <> True) then
    begin
      WriteLn('ConnectFailReason: ' + rest.ConnectFailReason);
      WriteLn(rest.LastErrorText);
      Exit;
    end;

  //  Note: The above code does not need to be repeatedly called for each REST request.
  //  The rest object can be setup once, and then many requests can be sent.  Chilkat will automatically
  //  reconnect within a FullRequest* method as needed.  It is only the very first connection that is explicitly
  //  made via the Connect method.

  //  Use this online tool to generate code from sample JSON:
  //  Generate Code to Create JSON

  //  The following JSON is sent in the request body.

  //  {
  //    "TableName": "Thread"
  //  }

  json := TJsonObject.Create;
  json.UpdateString('TableName','Thread');

  rest.AddHeader('Content-Type','application/x-amz-json-1.0');
  rest.AddHeader('X-Amz-Target','DynamoDB_20120810.DeleteTable');
  rest.AddHeader('Accept-Encoding','identity');

  sbRequestBody := TStringBuilder.Create;
  json.EmitSb(sbRequestBody);
  sbResponseBody := TStringBuilder.Create;
  success := rest.FullRequestSb('POST','/',sbRequestBody,sbResponseBody);
  if (success <> True) then
    begin
      WriteLn(rest.LastErrorText);
      Exit;
    end;
  respStatusCode := rest.ResponseStatusCode;
  WriteLn('response status code = ' + respStatusCode);
  if (respStatusCode >= 400) then
    begin
      WriteLn('Response Status Code = ' + respStatusCode);
      WriteLn('Response Header:');
      WriteLn(rest.ResponseHeader);
      WriteLn('Response Body:');
      WriteLn(sbResponseBody.GetAsString());
      Exit;
    end;

  jsonResponse := TJsonObject.Create;
  jsonResponse.LoadSb(sbResponseBody);

  jsonResponse.EmitCompact := False;
  WriteLn(jsonResponse.Emit());

  //  Sample JSON response:
  //  (Sample code for parsing the JSON response is shown below)

  //  {
  //    "TableDescription": {
  //      "TableArn": "arn:aws:dynamodb:us-west-2:123456789012:table/Thread",
  //      "ItemCount": 0,
  //      "ProvisionedThroughput": {
  //        "NumberOfDecreasesToday": 0,
  //        "ReadCapacityUnits": 5,
  //        "WriteCapacityUnits": 5
  //      },
  //      "TableName": "Thread",
  //      "TableSizeBytes": 0,
  //      "TableStatus": "DELETING"
  //    }
  //  }

  //  Sample code for parsing the JSON response...
  //  Use the following online tool to generate parsing code from sample JSON:
  //  Generate Parsing Code from JSON

  TableDescriptionTableArn := jsonResponse.StringOf('TableDescription.TableArn');
  TableDescriptionItemCount := jsonResponse.IntOf('TableDescription.ItemCount');
  TableDescriptionProvisionedThroughputNumberOfDecreasesToday := jsonResponse.IntOf('TableDescription.ProvisionedThroughput.NumberOfDecreasesToday');
  TableDescriptionProvisionedThroughputReadCapacityUnits := jsonResponse.IntOf('TableDescription.ProvisionedThroughput.ReadCapacityUnits');
  TableDescriptionProvisionedThroughputWriteCapacityUnits := jsonResponse.IntOf('TableDescription.ProvisionedThroughput.WriteCapacityUnits');
  TableDescriptionTableName := jsonResponse.StringOf('TableDescription.TableName');
  TableDescriptionTableSizeBytes := jsonResponse.IntOf('TableDescription.TableSizeBytes');
  TableDescriptionTableStatus := jsonResponse.StringOf('TableDescription.TableStatus');


  rest.Free;
  authAws.Free;
  json.Free;
  sbRequestBody.Free;
  sbResponseBody.Free;
  jsonResponse.Free;

end;

// ---------------------------------------------------------------------------

begin

  try
    RunDemo;
  except
    on E: Exception do
      WriteLn('Unhandled exception: ', E.ClassName, ': ', E.Message);
  end;

  WriteLn;
  {$IFDEF MSWINDOWS}
  WriteLn('Press Enter to exit...');
  ReadLn;
  {$ENDIF}
end.