Zig

PayPal - Cancel Sent Invoice

See more PayPal Examples

Cancels a sent invoice, by ID, and, optionally, sends a notification about the cancellation to the payer, merchant, and Cc: emails.

Note: This example requires Chilkat v9.5.0.65 or greater.

Zig

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

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

    // Note: Requires Chilkat v9.5.0.65 or greater.

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

    // Load our previously obtained access token. (see PayPal OAuth2 Access Token)
    const json_token = try chilkat.JsonObject.init();
    defer json_token.deinit();
    json_token.loadFile("qa_data/tokens/paypal.json") catch {};

    // Build the Authorization request header field value.
    const sb_auth = try chilkat.StringBuilder.init();
    defer sb_auth.deinit();
    // token_type should be "Bearer"
    sb_auth.append(try json_token.stringOf(alloc, "token_type")) catch {};
    sb_auth.append(" ") catch {};
    sb_auth.append(try json_token.stringOf(alloc, "access_token")) catch {};

    // Make the initial connection.
    // A single REST object, once connected, can be used for many PayPal REST API calls.
    // The auto-reconnect indicates that if the already-established HTTPS connection is closed,
    // then it will be automatically re-established as needed.
    const rest = try chilkat.Rest.init();
    defer rest.deinit();
    const b_auto_reconnect = true;
    rest.connect("api.sandbox.paypal.com", 443, true, b_auto_reconnect) catch {
        std.debug.print("{s}\n", .{try rest.getLastErrorText(alloc)});
        return;
    };

    // ----------------------------------------------------------------------------------------------
    // The code above this comment could be placed inside a function/subroutine within the application
    // because the connection does not need to be made for every request.  Once the connection is made
    // the app may send many requests..
    // ----------------------------------------------------------------------------------------------

    // Build the JSON request body containing the reminder information:
    const json = try chilkat.JsonObject.init();
    defer json.deinit();
    json.setEmitCompact(false);
    json.updateString("subject", "Past due") catch {};
    json.updateString("note", "Canceling invoice") catch {};
    json.updateBool("send_to_merchant", true) catch {};
    json.updateBool("send_to_payer", true) catch {};
    std.debug.print("{s}\n", .{try json.emit(alloc)});

    // The JSON created by the above code:

    //     {
    //       "subject": "Past due",
    //       "note": "Canceling invoice",
    //       "send_to_merchant": true,
    //       "send_to_payer": true
    //     }

    // Build a path using a previously-sent invoice ID.
    const sb_path = try chilkat.StringBuilder.init();
    defer sb_path.deinit();
    sb_path.append("/v1/invoicing/invoices/invoice_id/cancel") catch {};
    _ = sb_path.replace("invoice_id", "INV2-XPWZ-NUTQ-LNWB-P8NC");

    json.setEmitCompact(true);
    const sb_request_body = try chilkat.StringBuilder.init();
    defer sb_request_body.deinit();
    const sb_response_body = try chilkat.StringBuilder.init();
    defer sb_response_body.deinit();

    rest.addHeader("Content-Type", "application/json") catch {};
    rest.addHeader("Authorization", try sb_auth.getAsString(alloc)) catch {};
    json.emitSb(sb_request_body) catch {};

    rest.fullRequestSb("POST", try sb_path.getAsString(alloc), sb_request_body, sb_response_body) catch {
        std.debug.print("{s}\n", .{try rest.getLastErrorText(alloc)});
        return;
    };

    std.debug.print("Response Status Code = {d}\n", .{rest.getResponseStatusCode()});

    // In our testing, we received a 204 response, which is a success HTTP response code, but
    // differs from the PayPal REST API reference documentation, which states that a 202 response
    // is expected.  I suspect an error in the PayPal documentation, or in the PayPal responder.
    // Check for either 202 or 204..
    // Did we get a 202 accepted response?
    if ((rest.getResponseStatusCode() != 202) and (rest.getResponseStatusCode() != 204)) {
        std.debug.print("{s}\n", .{try sb_response_body.getAsString(alloc)});
        std.debug.print("Failed.\n", .{});
        return;
    }

    // The 202/204 response should be empty.  (Again, our experience differs from the online PayPal documentation..)
    std.debug.print("Success.\n", .{});
}