Sign a JWS with a Private Key

See more JSON Web Signatures (JWS) Examples

Demonstrates Jws.SetPrivateKey, which sets the private key used to create a signature. The example uses RS256 (RSASSA-PKCS1-v1_5 with SHA-256).

The file path is relative to the application's current working directory. An absolute path may also be used. Supply the path appropriate to your own environment.

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

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

    const jws = try chilkat.Jws.init();
    defer jws.deinit();

    // Protected header specifying RSASSA-PKCS1-v1_5 with SHA-256 (RS256).
    const header = try chilkat.JsonObject.init();
    defer header.deinit();
    header.updateString("alg", "RS256") catch {};
    jws.setProtectedHeader(0, header) catch {
        std.debug.print("{s}\n", .{try jws.getLastErrorText(alloc)});
        return;
    };

    const b_include_bom = false;
    jws.setPayload("This is the content to sign.", "utf-8", b_include_bom) catch {
        std.debug.print("{s}\n", .{try jws.getLastErrorText(alloc)});
        return;
    };

    // The file path is relative to the application's current working directory.  An absolute path
    // may also be used.  Supply the path appropriate to your own environment.
    // Load the signer's private key and set it for signature 0.
    const priv_key = try chilkat.PrivateKey.init();
    defer priv_key.deinit();
    priv_key.loadPemFile("qa_data/signer_privkey.pem") catch {
        std.debug.print("{s}\n", .{try priv_key.getLastErrorText(alloc)});
        return;
    };

    jws.setPrivateKey(0, priv_key) catch {
        std.debug.print("{s}\n", .{try jws.getLastErrorText(alloc)});
        return;
    };

    const jws_compact = jws.createJws(alloc) catch {
        std.debug.print("{s}\n", .{try jws.getLastErrorText(alloc)});
        return;
    };

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