Struct InvoicePosition 

pub struct InvoicePosition {
    pub number: u32,
    pub text: String,
    pub kind: BillingPositionKind,
    pub quantity: Decimal,
    pub unit: QuantityUnit,
    pub unit_price_eur: Decimal,
    pub net_eur: Decimal,
    pub artikel_id: Option<String>,
    pub lastvariable_preisposition_json: Option<Value>,
    pub trace: CalculationTrace,
}

One line item in a grid settlement.

Carries raw numbers for the service layer to map into the required format (BO4E Rechnungsposition, EN16931 UBL, etc.).

Invariant: net_eur == (quantity × unit_price_eur).round_dp(5).

Fields

number: u32

1-based sequence number.

text: String

Human-readable position description.

kind: BillingPositionKind

Semantic position kind — used by the service layer to set Rechnungsposition.artikelnummer (BDEW INVOIC AHB requirement).

quantity: Decimal

Metered or contracted quantity.

unit: QuantityUnit

Unit of measure.

unit_price_eur: Decimal

Unit price in EUR (already converted from ct where applicable).

net_eur: Decimal

Net amount in EUR, rounded to 5 decimal places.

May be negative for credit positions (Mindermengen, Gutschriften).

artikel_id: Option<String>

BDEW Artikel-ID for positions that use the new format (post-BK6-20-160).

Used for:

• NNE Strom (GPKE PIDs 31001/31006): BNetzA Netznutzungspreisblatt article IDs (e.g. "1-02-5-001" for NS Grundpreis-/Arbeitspreissystem Arbeitspreis). The service layer populates this from the PreisblattNetznutzung Artikel-ID.
• AWH Gas Sperrprozesse (PID 31011): "2-01-7-001" (Sperrung) / "2-01-7-002" (Entsperrung) populated automatically by calculate_gas_awh_invoice().
• MSB (PID 31009): "4-02-0-xxx" format from section 3.5 of the codelist, populated by the service layer from the product/Konfigurationsprodukt code.

For Gas NNE, MMM, Konzessionsabgabe and Blindmehrarbeit, the classic artikelnummer (via BillingPositionKind) takes precedence; this field is None.

Source: BDEW Codeliste Artikelnummern und Artikel-ID v5.6 (valid 01.09.2025).

lastvariable_preisposition_json: Option<Value>

§14a Modul 3: serialized LastvariablePreisposition BO4E COM for this position.

Set when kind == NneArbeitModul3. Carries the pricing formula parameters (SPOTPREIS method, preisreferenz, preisBezugseinheit) from the PreisblattNetznutzung.lastvariablePreispositionen used to derive unit_price_eur.

Stored as raw serde_json::Value so that grid-billing remains rubo4e-free. The service layer (netzbilanzd, billingd) can deserialize to rubo4e::current::LastvariablePreisposition for Rechnungsposition.zusatzAttribute embedding, enabling ERP-side validation and portal display of the per-dispatch tariff breakdown.

None for all other position kinds.

trace: CalculationTrace

Full audit trace for this position.

Answers “why is this amount here?” and carries all legal references.

Trait Implementations

impl Clone for InvoicePosition

fn clone(&self) -> InvoicePosition

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for InvoicePosition

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.