Multi-Currency

Flow ID: CF-33 | Module(s): eshop, Currency domain | Complexity: Medium Last Updated: 2026-04-26

Business Context

Currencies stored with ISO 4217 code, symbol, and exchange rate. Base currency (from registry DEFAULT_CURRENCY) has rate=1.0. Other currencies multiply prices at display time only — all database storage is in base currency.

Key business behaviors:

Default currency cannot be deactivated
Cart stores currency_code at creation (default EUR)
Frontend: Vuex getSelectedCurrency getter triggers reactive price recalculation
Feeds: ?curr= URL parameter for XML currency conversion

API Reference

REST Endpoints

Method	Path	Auth	Description
GET	`/rest/currency/currency`	Guest	List currencies (filter by code, active, symbol)
GET	`/rest/currency/currency/item`	Guest	Get single currency by filter (e.g. `filter[code]=EUR`)
GET	`/rest/currency/currency/{id}`	Guest	Get single currency
POST	`/rest/currency/currency`	Backend	Create currency
POST	`/rest/currency/currency/{id}`	Backend	Update currency
DELETE	`/rest/currency/currency/{id}`	Backend	Delete currency

Available filters: id (exact), code (exact), active (exact), symbol (partial) Available sorts: id, code, rate, active

Routes are defined in application/config/rest_routes.php (lines 292-297, 1296-1302) with both bare and language-prefixed variants ((\w{2})/rest/currency/currency/...). The item route is registered before the (:num) show route to avoid wildcard conflicts.

Legacy Storefront (AJAX)

URL Pattern	Controller	Method
`POST /setCustomerSessionCurrencyId`	`Webrun.php`	`setCustomerSessionCurrencyId()`

Code Flow

Step 1: Storefront Initialization

File: ecommercen/core/Adv_front_controller.php — constructor (line 96-116)

On every storefront page load the front controller:

Loads the default currency from registry: getDefaultCurrency() resolves ESHOP.DEFAULT_CURRENCY to a currency entity.
Fetches all active currencies and indexes them by ID: getResultObjectAsIndexedArray($this->currencies_model->getActiveCurrencies(), 'id').
Checks for a ?curr= query parameter via currencyFromQueryString() — if present and the code matches an active currency, stores its ID in session.
During initializeCustomerSessionData(), if no currencyId exists in session, defaults to getDefaultCurrencyId() (the registry value).
Sets $this->currentCurrency from the active currencies array using the session currency ID.

Step 2: Currency Data Passed to Vue

File: ecommercen/core/Adv_front_controller.php — renderVueJson() (line 756-758)

The current currency object is injected into the Vue initial state as selectedCurrency:

php

if (!isset($this->render['jsonState']['selectedCurrency'])) {
    $this->render['jsonState']['selectedCurrency'] = $this->activeCurrencies[$this->cSData['currencyId']];
}

The activeCurrencies array is also passed to the Blade/PHP render context (line 608) for server-side templates.

Step 3: Vue Reactivity

File: assets/vue/data-components/InitialData.vue — mounts selectedCurrency into Vuex via setSelectedCurrency action.

Store files:

State: assets/vue/store/state.js — selectedCurrency: [] (initialized empty, hydrated from server)
Getter: assets/vue/store/getters.js — getSelectedCurrency: state => state.selectedCurrency
Utility getter: getPriceUsingCurrency: (state) => (price) => (price * state.selectedCurrency.rate).toFixed(2)
Mutation: assets/vue/store/mutations.js — setSelectedCurrency(state, selectedCurrency)
Action: assets/vue/store/actions.js — setSelectedCurrency({ commit }, selectedCurrency)

Components read getSelectedCurrency and apply the rate at display time:

javascript

// AdvProductCard.vue
priceWithSign (priceString, priceSign) {
  return (parseFloat(priceString) * this.getSelectedCurrency.rate).toFixed(2) + priceSign
}
getSign () {
  return this.getSelectedCurrency.symbol
}

Step 4: Currency Switching (AJAX)

File: application/views/main/components/footer/footer_js.php (line 477-488)

When a customer clicks a .setCurrencyButton element, jQuery posts the currencyId to the URL produced by site_url('setCustomerSessionCurrencyId'):

javascript

$(document).on('click', '.setCurrencyButton', function (event) {
    var currencyId = event.target.getAttribute("data-id")
    $.ajax({
        type: "POST",
        url: site_url('setCustomerSessionCurrencyId'),
        dataType: "json",
        data: {'currencyId': currencyId}
    }).done(function (data) {
        if (data.result == 'success') {
            location.reload()
        } else {
            alert('<?= t(\'generic.error\'); ?>')
        }
    }).fail(function () {
        alert('<?= t(\'generic.error\'); ?>')
    })
})

File: application/controllers/Webrun.php — setCustomerSessionCurrencyId() (line 272-293)

The endpoint validates:

Request is AJAX (is_ajax_request())
Posted currencyId is a numeric digit string (ctype_digit)
Currency exists and is active (currencies_model->getRecord(['id' => ..., 'active' => true]))

On success, sets currencyId in CI session via set_userdata() and returns {"result": "success"}. The page reloads and the front controller picks up the new session currency.

Step 5: Currency in Feed Generation

File: ecommercen/feeds/core/AdvXml.php — constructor (line 27-29)

Feed XML controllers accept ?curr=CODE to generate prices in a specific currency:

php

$currencyCode = $this->input->get('curr');
$this->activeCurrencies = getResultObjectAsIndexedArray($this->currencies_model->getActiveCurrencies(), 'code');
$this->currency = $this->activeCurrencies[$currencyCode] ?? getDefaultCurrency();

Product URLs in multi-currency feeds include ?curr=CODE via siteUrlWithCurrency() so customers land on the storefront with that currency pre-selected.

Step 6: Currency at Order Placement

File: src/Domains/Checkout/PlaceOrderService.php (resolveOrderCurrency())

When an order is placed via the modern REST checkout, PlaceOrderService resolves the cart's currency from the database via the private resolveOrderCurrency(?string $cartCurrencyCode) method:

Calls CurrencyRepository::matchOne(new Filter('code', $cartCurrencyCode)) to look up the currency matching the cart's stored currency_code.
If the cart code is absent or unmatched, falls back to matchOne(new Filter('active', 1)) — the first active currency.
Throws RuntimeException if no active currency is found at all (misconfigured shop).

The resolved CurrencyEntity populates all three currency columns on the order row: order_currency (ISO code), currency_id (DB primary key), and currency_rate (exchange rate snapshot). This ensures the order record accurately reflects the rate in effect at placement time, not a hardcoded fallback.

Frontend Components

javascript

displayPrice = basePrice * selectedCurrency.rate
displaySymbol = selectedCurrency.symbol

Components that apply selectedCurrency.rate at render time: AdvCartProductRow.vue, CheckoutPage.vue, AdvProductCard.vue, AdvCartProductList.vue, AdvCartProductBundleDisplay.vue, CheckoutGiftPackaging.vue, AfterAddToCartModal.vue, GiftCardPage.vue, AdvOrderTransportersExternal.vue, AdvOrderTransportersMultiple.vue

The wishlist page (assets/main/js/components/wishlist-actions.js) reads selectedCurrency from window.advAppContext.vueData.initialData.selectedCurrency for GA4 tracking events.

Data Model

`currencies`

Column	Type	Description
`id`	int (PK, AI)	Currency identifier
`code`	varchar	ISO 4217 code (e.g., `EUR`, `USD`, `GBP`)
`num`	varchar	ISO 4217 numeric code (e.g., `978` for EUR)
`symbol`	varchar	Display symbol (e.g., `$`)
`rate`	decimal	Exchange rate relative to base currency (base = 1.0)
`active`	tinyint	Whether currency is available on storefront

`shop_order` (currency columns)

Column	Type	Description
`order_currency`	varchar	ISO 4217 code at time of order (e.g., `EUR`)
`currency_id`	int	FK to `currencies.id` at order time
`currency_rate`	decimal	Exchange rate snapshot at order time

Domain Layer

Component	Path
Service	`src/Domains/Currency/Currency/Service.php`
WriteService	`src/Domains/Currency/Currency/WriteService.php`
Validator	`src/Domains/Currency/Currency/Validator.php`
WriteData	`src/Domains/Currency/Currency/WriteData.php`
ListRequest	`src/Domains/Currency/Currency/ListRequest.php`
Entity	`src/Domains/Currency/Currency/Repository/Entity.php`
Repository	`src/Domains/Currency/Currency/Repository/Repository.php`
RepositoryConfigurator	`src/Domains/Currency/Currency/Repository/RepositoryConfigurator.php`
WriteRepository	`src/Domains/Currency/Currency/Repository/WriteRepository.php`
REST Controller	`src/Rest/Currency/Controllers/Currency.php`
Resource	`src/Rest/Currency/Resources/Currency/Resource.php`
Collection	`src/Rest/Currency/Resources/Currency/Collection.php`
Domain DI	`src/Domains/Currency/container.php`
REST DI	`src/Rest/Currency/container.php`

Legacy Model

Model	Path	Key Methods
`Adv_currencies_model`	`ecommercen/eshop/models/Adv_currencies_model.php`	`getActiveCurrencies()`, `getRecords()`, `getRecord()`, `add()`, `edit()`

Helper Functions

All defined in ecommercen/helpers/shopmodule_helper.php:

Function	Purpose
`getDefaultCurrency()`	Returns the currency object for `ESHOP.DEFAULT_CURRENCY` (cached via PSCache)
`getDefaultCurrencyId()`	Returns the registry value `ESHOP.DEFAULT_CURRENCY`
`getSelectedCurrencyData()`	Returns currency object for the session's `currencyId` (falls back to default)
`getCurrencyData($id)`	Returns currency object by ID (cached)
`getActiveCurrencies()`	Returns all active currencies from the model
`getActiveCurrenciesForDropdown()`	Returns `[id => "CODE (symbol)"]` array for HTML selects
`applyCurrencyRate($amount, $rate)`	`formatNumber($amount * $rate)`
`applyCurrency($amount, $currency)`	`formatNumber($amount * $currency->rate) . $currency->symbol`

Configuration

Registry Keys

Group	Key	Purpose	Set In
`ESHOP`	`DEFAULT_CURRENCY`	ID of the base currency (rate=1.0). Set during initial seed.	`Adv_settings.php` > Other Settings

The default currency is selected from the active currencies dropdown in the admin settings panel (ecommercen/settings/controllers/Adv_settings.php, line 1832/1916).

Currencies admin is registered in application/config/admin_menu.php under the SETTINGS group:

php

[
    'route' => 'currencies_admin',
    'icon' => t('admin.menu.currencies.icon'),
    'label' => t('admin.menu.currencies.label'),
    'roles' => [AUTH_ROLE_ADVISABLE, AUTH_ROLE_ADMIN],
    'group' => 'SETTINGS'
]

REST Policies

Defined in application/config/rest_policies.php:

php

Currency::class => [
    'defaults' => ['auth' => 'backend'],
    'methods'  => [
        'index' => ['auth' => 'guest'],
        'show'  => ['auth' => 'guest'],
        'item'  => ['auth' => 'guest'],
    ],
],

Read endpoints (index, show, item) are public (guest). Write endpoints (store, update, destroy) require backend JWT authentication.

Admin Route

application/config/routes.php:666-669

php

$route['currencies_admin'] = 'eshop/currencies_admin/index';
$route['currencies_admin/(.+)'] = 'eshop/currencies_admin/$1';
$route['(\w{2})/currencies_admin'] = 'eshop/currencies_admin/index';
$route['(\w{2})/currencies_admin/(.+)'] = 'eshop/currencies_admin/$2';

Client Extension Points

Admin Controller Override

The admin CRUD controller uses the standard thin-wrapper pattern:

File: application/modules/eshop/controllers/Currencies_admin.php

php

class Currencies_admin extends Adv_currencies_admin
{
    //
}

Client repos can override this file at application/modules/eshop/controllers/Currencies_admin.php to add custom validation, fields, or behavior (e.g., restricting which currencies can be created).

DI Container Overrides (Client Repos)

Override Domain layer services via custom/Domains/container.php:

php

// Override the RepositoryConfigurator to add custom relations
$services->set(\Custom\Domains\Currency\Currency\Repository\RepositoryConfigurator::class);
$services->alias(
    \Advisable\Domains\Currency\Currency\Repository\RepositoryConfigurator::class,
    \Custom\Domains\Currency\Currency\Repository\RepositoryConfigurator::class
);

// Override WriteService to add custom validation logic
$services->set(\Custom\Domains\Currency\Currency\WriteService::class);
$services->alias(
    \Advisable\Domains\Currency\Currency\WriteService::class,
    \Custom\Domains\Currency\Currency\WriteService::class
);

Model Override

Model	Override In
`Adv_currencies_model`	`application/modules/eshop/models/Adv_currencies_model.php`

Storefront Currency Switcher

The jQuery handler in footer_js.php targets .setCurrencyButton elements. Client themes can customize the switcher UI by placing currency buttons with data-id attributes in their template. The activeCurrencies array is available in the PHP render context.

Business Rules

Default Currency Protection

The default currency (identified by ESHOP.DEFAULT_CURRENCY registry value) cannot be deactivated. In Adv_currencies_admin::edit() (line 81-83), if the edited currency is the default, the active flag is forced to true:

php

if ($this->defaultCurrency->id == $id) {
    $currency['active'] = true;
}

Rate Application Formula

All prices in the database are stored in the base currency. Conversion is display-only:

displayPrice = basePrice * selectedCurrency.rate

PHP helper: applyCurrencyRate(float $amount, float $rate) returns formatNumber($amount * $rate)
PHP helper with symbol: applyCurrency(float $amount, object $currency) returns formatted price + symbol
Vue getter: getPriceUsingCurrency(price) returns (price * state.selectedCurrency.rate).toFixed(2)

The base currency always has rate = 1.0, so multiplication is a no-op for the default.

Active Toggle

Only currencies with active = 1 are:

Available on the storefront currency switcher (getActiveCurrencies())
Selectable via the session switch endpoint (validated in Webrun::setCustomerSessionCurrencyId())
Available in feed generation (AdvXml::__construct())

Deactivating a currency does not affect existing orders that were placed with that currency — the rate is snapshotted at order time.

Session Persistence

Currency selection is stored in CI session as currencyId (the integer primary key from the currencies table).
If a customer's session has no currencyId, the front controller defaults to getDefaultCurrencyId().
The ?curr=CODE query parameter overrides the session currency (used by feed URLs and direct links).

Validation

The Validator class (src/Domains/Currency/Currency/Validator.php) defines validateForCreate() and validateForUpdate() methods, but currently contains no specific rules — validation is open. Required fields for creation are enforced by WriteData: code, num, symbol, rate.

Known Issues & Security Gaps

Order currency snapshot — RESOLVED (fix #169, 2026-04-24). PlaceOrderService::resolveOrderCurrency() now looks up the cart's currency_code against the currencies table at order-placement time and snapshots currency_id, currency_rate, and order_currency on the order row. Falls back to the first active currency when the code can't be matched; throws RuntimeException if no active currency is configured. Citation: src/Domains/Checkout/PlaceOrderService.php (see resolveOrderCurrency() and the order-data block).
Currency WriteService Validator contains no specific validation rules — all writes are unchecked at the domain validation layer. Field presence is enforced only by WriteData constructor typing. Any constraints beyond required-field presence (e.g., valid ISO 4217 code format, positive rate, unique code) are absent. Citation: src/Domains/Currency/Currency/Validator.php.

Tests

File	Type	Coverage
`tests/Unit/Domains/Currency/Currency/ServiceTest.php`	Unit	Service layer
`tests/Integration/Domains/Currency/Currency/ServiceTest.php`	Integration	Service layer (DB)
`tests/Integration/Domains/Currency/Currency/RepositoryTest.php`	Integration	Repository layer (DB)
`tests/Unit/Rest/Currency/Resources/Currency/ResourceTest.php`	Unit	REST Resource transformer
`tests/Unit/Rest/Currency/Resources/Currency/CollectionTest.php`	Unit	REST Collection transformer

No dedicated tests cover the currency-switching AJAX flow (Webrun::setCustomerSessionCurrencyId()), the front-controller initialization path, or feed currency resolution.

CF-01 Product Browsing — prices displayed in selected currency
CF-02 Product Detail — product prices converted at display time
CF-05 Cart — cart stores currency_code at creation
CF-08 Payment Processing — payment gateway receives currency code (e.g., PayPal currency_code)
IN-01 Feed Generation — ?curr= parameter for multi-currency XML feeds
AD-36 Currency Management — admin CRUD for currencies

Multi-Currency ​

Business Context ​

API Reference ​

REST Endpoints ​

Legacy Storefront (AJAX) ​

Code Flow ​

Step 1: Storefront Initialization ​

Step 2: Currency Data Passed to Vue ​

Step 3: Vue Reactivity ​

Step 4: Currency Switching (AJAX) ​

Step 5: Currency in Feed Generation ​

Step 6: Currency at Order Placement ​

Frontend Components ​

Data Model ​

currencies ​

shop_order (currency columns) ​

Domain Layer ​

Legacy Model ​

Helper Functions ​

Configuration ​

Registry Keys ​

Admin Menu ​

REST Policies ​

Admin Route ​

Client Extension Points ​

Admin Controller Override ​

DI Container Overrides (Client Repos) ​

Model Override ​

Storefront Currency Switcher ​

Business Rules ​

Default Currency Protection ​

Rate Application Formula ​

Active Toggle ​

Session Persistence ​

Validation ​

Known Issues & Security Gaps ​

Tests ​

Related Flows ​

Multi-Currency

Business Context

API Reference

REST Endpoints

Legacy Storefront (AJAX)

Code Flow

Step 1: Storefront Initialization

Step 2: Currency Data Passed to Vue

Step 3: Vue Reactivity

Step 4: Currency Switching (AJAX)

Step 5: Currency in Feed Generation

Step 6: Currency at Order Placement

Frontend Components

Data Model

`currencies`

`shop_order` (currency columns)

Domain Layer

Legacy Model

Helper Functions

Configuration

Registry Keys

Admin Menu

REST Policies

Admin Route

Client Extension Points

Admin Controller Override

DI Container Overrides (Client Repos)

Model Override

Storefront Currency Switcher

Business Rules

Default Currency Protection

Rate Application Formula

Active Toggle

Session Persistence

Validation

Known Issues & Security Gaps

Tests

Related Flows