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Pascal (Lazarus/Delphi)

DynamoDB - DescribeTable

See more Amazon DynamoDB Examples

Returns information about the table, including the current status of the table, when it was created, the primary key schema, and any indexes on the table.

Chilkat Pascal (Lazarus/Delphi) Downloads

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;
  AttributeName: string;
  AttributeType: string;
  KeyType: string;
  IndexArn: string;
  IndexName: string;
  IndexSizeBytes: Integer;
  ItemCount: Integer;
  ProjectionProjectionType: string;
  j: Integer;
  count_j: Integer;
  TableTableArn: string;
  TableCreationDateTime: string;
  TableItemCount: Integer;
  TableProvisionedThroughputNumberOfDecreasesToday: Integer;
  TableProvisionedThroughputReadCapacityUnits: Integer;
  TableProvisionedThroughputWriteCapacityUnits: Integer;
  TableTableName: string;
  TableTableSizeBytes: Integer;
  TableTableStatus: string;
  i: Integer;
  count_i: Integer;

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.DescribeTable" \
  //    -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.DescribeTable');
  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)

  //  {
  //    "Table": {
  //      "TableArn": "arn:aws:dynamodb:us-west-2:123456789012:table/Thread",
  //      "AttributeDefinitions": [
  //        {
  //          "AttributeName": "ForumName",
  //          "AttributeType": "S"
  //        },
  //        {
  //          "AttributeName": "LastPostDateTime",
  //          "AttributeType": "S"
  //        },
  //        {
  //          "AttributeName": "Subject",
  //          "AttributeType": "S"
  //        }
  //      ],
  //      "CreationDateTime": 1.363729002358E9,
  //      "ItemCount": 0,
  //      "KeySchema": [
  //        {
  //          "AttributeName": "ForumName",
  //          "KeyType": "HASH"
  //        },
  //        {
  //          "AttributeName": "Subject",
  //          "KeyType": "RANGE"
  //        }
  //      ],
  //      "LocalSecondaryIndexes": [
  //        {
  //          "IndexArn": "arn:aws:dynamodb:us-west-2:123456789012:table/Thread/index/LastPostIndex",
  //          "IndexName": "LastPostIndex",
  //          "IndexSizeBytes": 0,
  //          "ItemCount": 0,
  //          "KeySchema": [
  //            {
  //              "AttributeName": "ForumName",
  //              "KeyType": "HASH"
  //            },
  //            {
  //              "AttributeName": "LastPostDateTime",
  //              "KeyType": "RANGE"
  //            }
  //          ],
  //          "Projection": {
  //            "ProjectionType": "KEYS_ONLY"
  //          }
  //        }
  //      ],
  //      "ProvisionedThroughput": {
  //        "NumberOfDecreasesToday": 0,
  //        "ReadCapacityUnits": 5,
  //        "WriteCapacityUnits": 5
  //      },
  //      "TableName": "Thread",
  //      "TableSizeBytes": 0,
  //      "TableStatus": "ACTIVE"
  //    }
  //  }

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

  TableTableArn := jsonResponse.StringOf('Table.TableArn');
  TableCreationDateTime := jsonResponse.StringOf('Table.CreationDateTime');
  TableItemCount := jsonResponse.IntOf('Table.ItemCount');
  TableProvisionedThroughputNumberOfDecreasesToday := jsonResponse.IntOf('Table.ProvisionedThroughput.NumberOfDecreasesToday');
  TableProvisionedThroughputReadCapacityUnits := jsonResponse.IntOf('Table.ProvisionedThroughput.ReadCapacityUnits');
  TableProvisionedThroughputWriteCapacityUnits := jsonResponse.IntOf('Table.ProvisionedThroughput.WriteCapacityUnits');
  TableTableName := jsonResponse.StringOf('Table.TableName');
  TableTableSizeBytes := jsonResponse.IntOf('Table.TableSizeBytes');
  TableTableStatus := jsonResponse.StringOf('Table.TableStatus');
  i := 0;
  count_i := jsonResponse.SizeOfArray('Table.AttributeDefinitions');
  while i < count_i do
    begin
      jsonResponse.I := i;
      AttributeName := jsonResponse.StringOf('Table.AttributeDefinitions[i].AttributeName');
      AttributeType := jsonResponse.StringOf('Table.AttributeDefinitions[i].AttributeType');
      i := i + 1;
    end;

  i := 0;
  count_i := jsonResponse.SizeOfArray('Table.KeySchema');
  while i < count_i do
    begin
      jsonResponse.I := i;
      AttributeName := jsonResponse.StringOf('Table.KeySchema[i].AttributeName');
      KeyType := jsonResponse.StringOf('Table.KeySchema[i].KeyType');
      i := i + 1;
    end;

  i := 0;
  count_i := jsonResponse.SizeOfArray('Table.LocalSecondaryIndexes');
  while i < count_i do
    begin
      jsonResponse.I := i;
      IndexArn := jsonResponse.StringOf('Table.LocalSecondaryIndexes[i].IndexArn');
      IndexName := jsonResponse.StringOf('Table.LocalSecondaryIndexes[i].IndexName');
      IndexSizeBytes := jsonResponse.IntOf('Table.LocalSecondaryIndexes[i].IndexSizeBytes');
      ItemCount := jsonResponse.IntOf('Table.LocalSecondaryIndexes[i].ItemCount');
      ProjectionProjectionType := jsonResponse.StringOf('Table.LocalSecondaryIndexes[i].Projection.ProjectionType');
      j := 0;
      count_j := jsonResponse.SizeOfArray('Table.LocalSecondaryIndexes[i].KeySchema');
      while j < count_j do
        begin
          jsonResponse.J := j;
          AttributeName := jsonResponse.StringOf('Table.LocalSecondaryIndexes[i].KeySchema[j].AttributeName');
          KeyType := jsonResponse.StringOf('Table.LocalSecondaryIndexes[i].KeySchema[j].KeyType');
          j := j + 1;
        end;

      i := i + 1;
    end;



  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.