(MFC) Create JWT Using HS256, HS384, or HS512

Demonstrates how to create a JWT using HS256, HS384, or HS512. (HS256 is JWT's acronym for HMAC-SHA256.) When HMAC is used, the secret is a shared secret (i.e. password) that both client and server know beforehand.

This example also demonstrates how to include time constraints:

• nbf: Not Before Time
• exp: Expiration Time
• iat: Issue At Time

Chilkat C/C++ Library Downloads MS Visual C/C++ Libs

See Also: Using MFC CString in Chilkat

#include <CkJwt.h>
#include <CkJsonObject.h>

void ChilkatSample(void)
    {
    CkString strOut;

    // Demonstrates how to create an HMAC JWT using a shared secret (password).

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

    CkJwt jwt;

    // Build the JOSE header
    CkJsonObject jose;
    // Use HS256.  Pass the string "HS384" or "HS512" to use a different algorithm.
    bool success = jose.AppendString("alg","HS256");
    success = jose.AppendString("typ","JWT");

    // Now build the JWT claims (also known as the payload)
    CkJsonObject claims;
    success = claims.AppendString("iss","http://example.org");
    success = claims.AppendString("sub","John");
    success = claims.AppendString("aud","http://example.com");

    // Set the timestamp of when the JWT was created to now.
    int curDateTime = jwt.GenNumericDate(0);
    success = claims.AddIntAt(-1,"iat",curDateTime);

    // Set the "not process before" timestamp to now.
    success = claims.AddIntAt(-1,"nbf",curDateTime);

    // Set the timestamp defining an expiration time (end time) for the token
    // to be now + 1 hour (3600 seconds)
    success = claims.AddIntAt(-1,"exp",curDateTime + 3600);

    // Produce the smallest possible JWT:
    jwt.put_AutoCompact(true);

    const char *strJwt = jwt.createJwt(jose.emit(),claims.emit(),"secret");

    strOut.append(strJwt);
    strOut.append("\r\n");


    SetDlgItemText(IDC_EDIT1,strOut.getUnicode());

    }