Zig

Create JWT using a Brainpool EC Key

See more JSON Web Token (JWT) Examples

Demonstrates how to create a JWT using an EC private key. This is for JOSE headers having an "alg" member with any of the following values:

• BP160R1
• BP192R1
• BP224R1
• BP256R1
• BP320R1
• BP384R1
• BP512R1

This example also demonstrates how to include time constraints:

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

Zig

const std = @import("std");
const chilkat = @import("chilkat");

pub fn main(init: std.process.Init) !void {
    const alloc = init.arena.allocator();

    // Demonstrates how to create a JWT using a brainpool EC private key.

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

    const priv_key = try chilkat.PrivateKey.init();
    defer priv_key.deinit();

    // Load a brainpool EC key.
    priv_key.loadPemFile("c:/qa_data/pem/ec_brainpool_privKey.pem") catch {
        std.debug.print("{s}\n", .{try priv_key.getLastErrorText(alloc)});
        return;
    };

    // You can examine the curve name of the key you just loaded by getting the private in XML format:
    // <ECCKeyValue curve="CURVE_NAME">...</ECCKeyValue>
    std.debug.print("{s}\n", .{try priv_key.getXml(alloc)});

    const jwt = try chilkat.Jwt.init();
    defer jwt.deinit();

    // Build the JOSE header
    const jose = try chilkat.JsonObject.init();
    defer jose.deinit();
    // Use the brainpool curve name matching the private key you just loaded.
    // Use "BP256R1", or "BP384R1", etc.
    try jose.appendString("alg", "BP256R1");
    try jose.appendString("typ", "JWT");

    // Now build the JWT claims (also known as the payload)
    const claims = try chilkat.JsonObject.init();
    defer claims.deinit();
    try claims.appendString("iss", "http://example.org");
    try claims.appendString("sub", "John");
    try claims.appendString("aud", "http://example.com");

    // Set the timestamp of when the JWT was created to now.
    const cur_date_time = jwt.genNumericDate(0);
    try claims.addIntAt(-1, "iat", cur_date_time);

    // Set the "not process before" timestamp to now.
    try claims.addIntAt(-1, "nbf", cur_date_time);

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

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

    // Create the JWT token.  This is where the ECC signature is created.
    const token = try jwt.createJwtPk(alloc, try jose.emit(alloc), try claims.emit(alloc), priv_key);

    std.debug.print("{s}\n", .{token});
}