Zig
Mailgun Send Send HTML Email with Attachments and HTML Images

Sends an HTML email with images and attachments.
Chilkat Zig Downloads

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

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

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

    const http = try chilkat.Http.init();
    defer http.deinit();

    http.setLogin("api");
    http.setPassword("sending_api_key"); // Replace with your actual sending API key.

    const req = try chilkat.HttpRequest.init();
    defer req.deinit();
    req.setHttpVerb("POST");
    req.setPath("/v3/YOUR_DOMAIN_NAME/messages");
    req.setContentType("multipart/form-data");

    // Change YOUR_DOMAIN_NAME to something like "mg.your-domain.com".
    req.addParam("from", "Your Name <mailgun@YOUR_DOMAIN_NAME>");
    req.addParam("to", "Joe Example <joe@example.com>");
    req.addParam("subject", "Hello Joe Example");
    req.addParam("html", "<html><body><b>This is the HTML body</b><br><img src=\"cid:cidStarfish.jpg\"></body></html>");

    // An a attachd file
    const bd = try chilkat.BinData.init();
    defer bd.deinit();
    bd.loadFile("qa_data/hamlet.zip") catch {
        std.debug.print("Failed to load file attachment.\n", .{});
        return;
    };

    req.addBdForUpload("attachment", "hamlet.zip", bd, "application/zip") catch {};

    // add an image as CID
    bd.loadFile("qa_data/jpg/starfish.jpg") catch {
        std.debug.print("Failed to load HTML image.\n", .{});
        return;
    };

    req.addBdForUpload("inline", "cidStarfish.jpg", bd, "image/jpeg") catch {};

    const resp = try chilkat.HttpResponse.init();
    defer resp.deinit();
    http.httpSReq("api.mailgun.net", 443, true, req, resp) catch {
        std.debug.print("{s}\n", .{try http.getLastErrorText(alloc)});
        return;
    };

    const sb_response_body = try chilkat.StringBuilder.init();
    defer sb_response_body.deinit();
    resp.getBodySb(sb_response_body) catch {};
    const j_resp = try chilkat.JsonObject.init();
    defer j_resp.deinit();
    j_resp.loadSb(sb_response_body) catch {};
    j_resp.setEmitCompact(false);

    std.debug.print("Response Body:\n", .{});
    std.debug.print("{s}\n", .{try j_resp.emit(alloc)});

    const resp_status_code = resp.getStatusCode();
    std.debug.print("Response Status Code = {d}\n", .{resp_status_code});
    if (resp_status_code >= 400) {
        std.debug.print("Response Header:\n", .{});
        std.debug.print("{s}\n", .{try resp.getHeader(alloc)});
        std.debug.print("Failed.\n", .{});
        return;
    }

    // Sample JSON response:
    // (Sample code for parsing the JSON response is shown below)

    // {
    //   "id": "<20210429234809.1.2D550E1C94D3D98F@sandbox0e542e4c577f4bbb98c8bf6b6bca727b.mailgun.org>",
    //   "message": "Queued. Thank you."
    // }

    // Sample code for parsing the JSON response...
    // Use the following online tool to generate parsing code from sample JSON:
    // Generate Parsing Code from JSON

    _ = try j_resp.stringOf(alloc, "id");
    _ = try j_resp.stringOf(alloc, "message");
}