iati-transform

Transformations and rollups for IATI Activity data.
Part of the iati-crates ecosystem.

Overview

This crate provides pure, IO-free transformations for iati-types data structures —
designed for use in CLI tools, web services, and data pipelines.

Core functions

• Aggregate transactions by type, year, or currency
• Respect currency fallback (transaction.currency → activity.default_currency)
• Simple, functional design — no I/O, no side effects
• Works seamlessly with iati-xml for parsed IATI data

Example

use iati_transform::{aggregate_by_type, aggregate_by_year_and_type, FxCurrency};
use iati_types::{Activity, TxType, Transaction, Money, CurrencyCode};
use chrono::NaiveDate;
use rust_decimal::Decimal;

// Build a minimal IATI Activity
let mut a = Activity::new("ACT-1");
a.default_currency = Some(CurrencyCode::from("USD"));

a.transactions.push(Transaction::new(
    TxType::Disbursement,
    NaiveDate::from_ymd_opt(2023, 1, 1).unwrap(),
    Money {
        amount: Decimal::new(1000, 2),
        currency: None, // falls back to USD
        value_date: None,
    },
));

a.transactions.push(Transaction::new(
    TxType::Disbursement,
    NaiveDate::from_ymd_opt(2023, 2, 1).unwrap(),
    Money {
        amount: Decimal::new(500, 2),
        currency: Some(CurrencyCode::from("EUR")),
        value_date: None,
    },
));

// Aggregate by type in native currency space (no FX conversions)
let sums = aggregate_by_type(&[a], FxCurrency::Native);
let total_usd = sums.total_for(TxType::Disbursement, &CurrencyCode::from("USD"));
assert!(total_usd.is_some());

// Aggregate by year and transaction type
let year_sums = aggregate_by_year_and_type(&[a], FxCurrency::Native);
assert!(year_sums.total_for(2023, TxType::Disbursement, &CurrencyCode::from("USD")).is_some());