fix: adding ability to track revenue currency

core/src/main/java/com/amplitude/core/events/BaseEvent.kt

@@ -46,6 +46,7 @@ open class BaseEvent : EventOptions() {
         options.quantity?.let { quantity = it }
         options.productId?.let { productId = it }
         options.revenueType?.let { revenueType = it }
+        options.currency?.let { currency = it }
         options.extra?.let { extra = it }
         options.callback?.let { callback = it }
         options.partnerId?.let { partnerId = it }

core/src/main/java/com/amplitude/core/events/EventOptions.kt

@@ -39,6 +39,7 @@ open class EventOptions {
     var quantity: Int? = null
     var productId: String? = null
     var revenueType: String? = null
+    var currency: String? = null
     var extra: Map<String, Any>? = null
     var callback: EventCallBack? = null
     var partnerId: String? = null

core/src/main/java/com/amplitude/core/events/Revenue.kt

@@ -36,6 +36,11 @@ open class Revenue {
      */
     var revenueType: String? = null
 
+    /**
+     * The 3 letter currency code (optional).
+     */
+    var currency: String? = null
+
     /**
      * The Receipt field (required if you want to verify the revenue event).
      */
@@ -66,6 +71,7 @@ open class Revenue {
         internal const val REVENUE_QUANTITY = "\$quantity"
         internal const val REVENUE_PRICE = "\$price"
         internal const val REVENUE_TYPE = "\$revenueType"
+        internal const val REVENUE_CURRENCY = "\$currency"
         internal const val REVENUE_RECEIPT = "\$receipt"
         internal const val REVENUE_RECEIPT_SIG = "\$receiptSig"
         internal const val REVENUE = "\$revenue"
@@ -97,6 +103,7 @@ open class Revenue {
         eventProperties.put(REVENUE_QUANTITY, quantity)
         price?.let { eventProperties.put(REVENUE_PRICE, it) }
         revenueType?.let { eventProperties.put(REVENUE_TYPE, it) }
+        currency?.let { eventProperties.put(REVENUE_CURRENCY, it) }
         receipt?.let { eventProperties.put(REVENUE_RECEIPT, it) }
         receiptSig?.let { eventProperties.put(REVENUE_RECEIPT_SIG, it) }
         revenue?.let { eventProperties.put(REVENUE, it) }

core/src/main/java/com/amplitude/core/utilities/JSONUtil.kt

@@ -37,6 +37,7 @@ object JSONUtil {
         eventJSON.addValue("revenue", event.revenue)
         eventJSON.addValue("productId", event.productId)
         eventJSON.addValue("revenueType", event.revenueType)
+        eventJSON.addValue("currency", event.currency)
         eventJSON.addValue("location_lat", event.locationLat)
         eventJSON.addValue("location_lng", event.locationLng)
         eventJSON.addValue("ip", event.ip)

core/src/test/kotlin/com/amplitude/core/events/RevenueTest.kt

@@ -60,6 +60,23 @@ class RevenueTest {
         assertEquals(revenue.revenueType, revenueType)
     }
 
+    @Test
+    fun testRevenueCurrency() {
+        val revenue = Revenue()
+        assertEquals(revenue.currency, null)
+        val currency = "CAD"
+        revenue.currency = currency
+        assertEquals(revenue.currency, currency)
+
+        // verify that null and empty strings allowed
+        revenue.currency = null
+        assertNull(revenue.currency)
+        revenue.currency = ""
+        assertEquals(revenue.currency, "")
+        revenue.currency = currency
+        assertEquals(revenue.currency, currency)
+    }
+
     @Test
     fun testReceipt() {
         val revenue = Revenue()
@@ -79,11 +96,13 @@ class RevenueTest {
         revenue.revenueType = "testRevenueType"
         revenue.quantity = 20
         revenue.productId = "testProductId"
+        revenue.currency = "CAD"
         val event = revenue.toRevenueEvent()
         assertEquals(19.99, event.eventProperties?.get(Revenue.REVENUE_PRICE))
         assertEquals("testRevenueType", event.eventProperties?.get(Revenue.REVENUE_TYPE))
         assertEquals(20, event.eventProperties?.get(Revenue.REVENUE_QUANTITY))
         assertEquals("testProductId", event.eventProperties?.get(Revenue.REVENUE_PRODUCT_ID))
+        assertEquals("CAD", event.eventProperties?.get(Revenue.REVENUE_CURRENCY))
     }
 
     @Test
@@ -93,13 +112,15 @@ class RevenueTest {
         revenue.revenueType = "testRevenueType"
         revenue.quantity = 20
         revenue.productId = "testProductId"
+        revenue.currency = "CAD"
         val receipt = "testReceipt"
         val receiptSig = "testReceiptSig"
         revenue.setReceipt(receipt, receiptSig)
         revenue.properties = mutableMapOf(Pair("city", "san francisco"))
         val event = revenue.toRevenueEvent()
         assertEquals(receipt, event.eventProperties?.get(Revenue.REVENUE_RECEIPT))
         assertEquals(receiptSig, event.eventProperties?.get(Revenue.REVENUE_RECEIPT_SIG))
+        assertEquals("CAD", event.eventProperties?.get(Revenue.REVENUE_CURRENCY))
         assertEquals("san francisco", event.eventProperties?.get("city"))
     }