fix: adding currency property to events (#110)

Author: izaaz

gradle/wrapper/gradle-wrapper.properties

@@ -1,5 +1,7 @@
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-6.8.3-all.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-8.10-bin.zip
+networkTimeout=10000
+validateDistributionUrl=true
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists

src/main/java/com/amplitude/Event.java

@@ -144,6 +144,11 @@ public class Event {
    */
   public String revenueType;
 
+  /**
+   * The 3 letter revenue currency code for the item purchased.
+   */
+  public String currency;
+
   /**
    * An incrementing counter to distinguish events with the same user_id and timestamp from each
    * other. We recommend you send an event_id, increasing over time, especially if you expect events
@@ -271,6 +276,7 @@ public JSONObject toJsonObject() {
         event.put("revenue", revenue);
         event.put("productId", productId);
         event.put("revenueType", revenueType);
+        event.put("currency", currency);
       }
 
       event.put("event_id", replaceWithJSONNull(eventId));

src/test/java/com/amplitude/EventTest.java

@@ -76,6 +76,7 @@ public void testLogEventWithRevenue() {
     event.price = price;
     event.productId = productId;
     event.revenueType = revenueType;
+    event.currency = "USD";
 
     JSONObject truncatedEvent = event.toJsonObject();
     assertEquals(eventType, truncatedEvent.getString("event_type"));
@@ -85,6 +86,7 @@ public void testLogEventWithRevenue() {
     assertEquals(quantity, truncatedEvent.getInt("quantity"));
     assertEquals(productId, truncatedEvent.getString("productId"));
     assertEquals(revenueType, truncatedEvent.getString("revenueType"));
+    assertEquals("USD", truncatedEvent.getString("currency"));
   }
 
   @Test