Pascal (Lazarus/Delphi)
Pascal (Lazarus/Delphi)
Create a JWS into a StringBuilder
See more JSON Web Signatures (JWS) Examples
Demonstrates Jws.CreateJwsSb, which creates a JWS and writes it into a StringBuilder.
Background. JWS (JSON Web Signature) integrity-protects a payload with a signature or MAC. The header
alg names the algorithm; this example uses HMAC-SHA256 (HS256) with a symmetric MAC key.Chilkat Pascal (Lazarus/Delphi) Downloads
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.StringBuilder,
Chilkat.Jws,
Chilkat.JsonObject;
// ---------------------------------------------------------------------------
procedure RunDemo;
var
success: Boolean;
jws: TJws;
header: TJsonObject;
bIncludeBom: Boolean;
base64Key: string;
sbJws: TStringBuilder;
begin
success := False;
jws := TJws.Create;
// Set the protected header for signer 0, specifying the signature algorithm (alg).
header := TJsonObject.Create;
header.UpdateString('alg','HS256');
success := jws.SetProtectedHeader(0,header);
if (success = False) then
begin
WriteLn(jws.LastErrorText);
Exit;
end;
// Set the payload to be signed.
bIncludeBom := False;
success := jws.SetPayload('This is the content to sign.','utf-8',bIncludeBom);
if (success = False) then
begin
WriteLn(jws.LastErrorText);
Exit;
end;
// Provide the HMAC key (base64) for signer 0. In production, obtain the key from a secure source
// rather than hard-coding it.
base64Key := 'YWJjZGVmZ2hpamtsbW5vcHFyc3R1dnd4eXowMTIzNDU=';
success := jws.SetMacKey(0,base64Key,'base64');
if (success = False) then
begin
WriteLn(jws.LastErrorText);
Exit;
end;
// Create the JWS and write it into a StringBuilder.
sbJws := TStringBuilder.Create;
success := jws.CreateJwsSb(sbJws);
if (success = False) then
begin
WriteLn(jws.LastErrorText);
Exit;
end;
WriteLn(sbJws.GetAsString());
jws.Free;
header.Free;
sbJws.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.