Generator of ZUGFeRD XML

Summary

This crate generates an XML with the ZUGFeRD specification that can be embedded in PDF to generate E-invoice compliant with the EU regulations.

[!WARNING] This crate is pretty much work in progress.

Although you can generate a minimum and basic levels XML, this crate is more of a starting point and an invitation for feedback and collaboration. Breaking changes are not intended, but are not impossible either.

Installation

Add the crate:

cargo add zugferd

Import the crate:

use zugferd::{InvoiceBuilder,InvoiceTypeCode,CountryCode,CurrencyCode,SpecificationLevel};

[!WARNING] Although you can populate data into structs without the invoice builder, at this point I strongly suggest you use it. Breaking changes may occure. Besides, it takes care of conversion from Strings.

Initialize and pass first data:

let mut invoice_builder = InvoiceBuilder::new();

invoice_builder.set_business_process("process1")
    .set_invoice_type_code(InvoiceTypeCode::CommercialInvoice)
    .set_invoice_nr("INV-123456")
    .set_date_of_issue(chrono::NaiveDate::from_ymd_opt(2024,08,10).unwrap())
    .set_buyer_reference("BR-7890")
    .set_sellers_name("Seller Corp.")
    .set_sellers_specified_legal_organization("LegalOrg-001")
    .set_sellers_postal_trade_address_country_code(CountryCode::Germany)
    .set_sellers_specified_tax_registration("DE123456789")
    .set_buyers_name("Buyer Inc.")
    .set_buyers_specified_legal_organization("LegalOrg-002")
    .set_buyers_order_specified_document("OD-2024-001")
    .set_invoice_currency_code(CurrencyCode::Euro);

You can always check if the provided data enough for the specified level. (At this stage only "minimum", "basic wl" and "basic" are supported.)

match invoice_builder.all_fields_are_set(SpecificationLevel::Minimum) {
    Ok(_) => {
        //Carry on
        println!("All fields are set.");
    },
    Err(e) => {
        //Check what is missing
        println!("I want this: {}",e);
    }
}

Or simply

invoice_builder.all_fields_are_set(SpecificationLevel::Minimum)?;

Calculate your data further, for example:

let sum_net: f64 = 100.0;
let tax: f64 = sum_net * 19.0 /100.0;
let sum_gross: f64 = sum_net + tax;
let customer_paid_already: f64 = 50.0;

Pass missing data to the instance:

invoice_builder
    .set_monetary_summation_tax_basis_total_amount(sum_net)
    .set_monetary_summation_tax_total_amount(tax)
    .set_monetary_summation_grand_total_amount(sum_gross)
    .set_monetary_summation_due_payable_amount(sum_gross - customer_paid_already);

Generate XML:

let mut xml_string: String = String::new();

match invoice_builder.to_xml_string(SpecificationLevel::Minimum) {
    Ok(string_returned_by_function) => {
        xml_string = string_returned_by_function;
    },
    Err(e) => {
        println!("Something happened at the XML generation: {}",e);
    }
}

println!("Generated ZUGFeRD XML: {}",xml_string);

Please check main.rs for further examples.

Roadmap

• generation of minimum level
• generation of basic level without lines
• generation of basic level
• generation of EN 16931 level
• generation of extended level
• validation of all levels
• parsing of all levels
• embedding the generated XML into PDF/A-3 files

Further reading

ZUGFeRD 2.3 specification