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Zig

Send Signed Email using PFX File

Demonstrates how to send a signed email using a digital certificate w/ private key stored in a PFX file.

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

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

    var success: bool = false;

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

    // The mailman object is used for sending and receiving email.
    const mailman = try chilkat.MailMan.init();
    defer mailman.deinit();

    // Set the SMTP server.
    mailman.setSmtpHost("smtp.mymailserver.com");

    // Create a new email object
    const email = try chilkat.Email.init();
    defer email.deinit();

    email.setSubject("This email is signed");
    email.setBody("This is a digitally signed mail");
    email.setFrom("Chilkat Admin <admin@chilkatsoft.com>");
    success = if (email.addTo("Chilkat Support", "support@chilkatsoft.com")) true else |_| false;

    // Indicate that the email should be sent signed.
    email.setSendSigned(true);

    // Tell the mailman to use a PFX file as a source for locating
    // the certificate and private key required for signing.
    // The certificate chosen for signing will be the one that
    // matches the sender's email address, which also has
    // a private key.  All intermediate certs in the chain of
    // authentication, up to and including the root, will
    // be included in the signature.
    success = if (mailman.addPfxSourceFile("/pfx_files/chilkatsoft_secret.pfx", "secret")) true else |_| false;
    if (!success) {
        std.debug.print("{s}\n", .{try mailman.getLastErrorText(alloc)});
        return;
    }

    // Signed email can be sent in two different ways.
    // In a multipart/signed email, the signature is attached as a separate MIME part.
    // In an opaque email (signedData) the content of the email is encapsulated within the signature
    // and the email is sent as "application/pkcs7-mime".
    // Either should be fine, but some receiving systems might require one or the other..
    mailman.setOpaqueSigning(false);

    // Send a signed email.
    success = if (mailman.sendEmail(email)) true else |_| false;
    if (!success) {
        std.debug.print("{s}\n", .{try mailman.getLastErrorText(alloc)});
    } else {
        // The LastErrorText property provides information
        // even when successful.
        std.debug.print("{s}\n", .{try mailman.getLastErrorText(alloc)});
        std.debug.print("Mail Sent!\n", .{});
    }
}