Merge pull request #9 from uma-universal-money-address/feat/payrespde…

…cimals

Add the decimals field to payreq paymentinfo for convenience

javatest/src/test/java/me/uma/javatest/UmaTest.java

@@ -111,6 +111,7 @@ public void testGetPayReqResponseSync() throws Exception {
                 new TestUmaInvoiceCreator(),
                 "metadata",
                 "USD",
+                2,
                 12345L,
                 0L,
                 List.of(),
@@ -134,6 +135,7 @@ public void testGetPayReqResponseFuture() throws Exception {
                 new TestUmaInvoiceCreator(),
                 "metadata",
                 "USD",
+                2,
                 12345L,
                 0L,
                 List.of(),

uma-sdk/src/commonMain/kotlin/me/uma/UmaProtocolHelper.kt

@@ -359,6 +359,9 @@ class UmaProtocolHelper @JvmOverloads constructor(
      * @param invoiceCreator The [UmaInvoiceCreator] that will be used to create the invoice.
      * @param metadata The metadata that will be added to the invoice's metadata hash field.
      * @param currencyCode The code of the currency that the receiver will receive for this payment.
+     * @param currencyDecimals The number of digits after the decimal point for the receiving currency. For example,
+     *     USD has 2 decimal places. This should align with the `decimals` field returned for the chosen currency in the
+     *     LNURLP response.
      * @param conversionRate The conversion rate. It is the numer of milli-satoshis per the smallest unit of the
      *     specified currency (for example: cents in USD). This rate is committed to by the receiving VASP until the
      *     invoice expires.
@@ -377,6 +380,7 @@ class UmaProtocolHelper @JvmOverloads constructor(
         invoiceCreator: UmaInvoiceCreator,
         metadata: String,
         currencyCode: String,
+        currencyDecimals: Int,
         conversionRate: Double,
         receiverFeesMillisats: Long,
         receiverChannelUtxos: List<String>,
@@ -388,6 +392,7 @@ class UmaProtocolHelper @JvmOverloads constructor(
             invoiceCreator,
             metadata,
             currencyCode,
+            currencyDecimals,
             conversionRate,
             receiverFeesMillisats,
             receiverChannelUtxos,
@@ -406,6 +411,9 @@ class UmaProtocolHelper @JvmOverloads constructor(
      * @param invoiceCreator The [UmaInvoiceCreator] that will be used to create the invoice.
      * @param metadata The metadata that will be added to the invoice's metadata hash field.
      * @param currencyCode The code of the currency that the receiver will receive for this payment.
+     * @param currencyDecimals The number of digits after the decimal point for the receiving currency. For example,
+     *     USD has 2 decimal places. This should align with the `decimals` field returned for the chosen currency in the
+     *     LNURLP response.
      * @param conversionRate The conversion rate. It is the number of milli-satoshis per the smallest unit of the
      *     specified currency (for example: cents in USD). This rate is committed to by the receiving VASP until the
      *     invoice expires.
@@ -424,6 +432,7 @@ class UmaProtocolHelper @JvmOverloads constructor(
         invoiceCreator: UmaInvoiceCreator,
         metadata: String,
         currencyCode: String,
+        currencyDecimals: Int,
         conversionRate: Double,
         receiverFeesMillisats: Long,
         receiverChannelUtxos: List<String>,
@@ -435,6 +444,7 @@ class UmaProtocolHelper @JvmOverloads constructor(
             invoiceCreator,
             metadata,
             currencyCode,
+            currencyDecimals,
             conversionRate,
             receiverFeesMillisats,
             receiverChannelUtxos,
@@ -450,6 +460,9 @@ class UmaProtocolHelper @JvmOverloads constructor(
      * @param invoiceCreator The [UmaInvoiceCreator] that will be used to create the invoice.
      * @param metadata The metadata that will be added to the invoice's metadata hash field.
      * @param currencyCode The code of the currency that the receiver will receive for this payment.
+     * @param currencyDecimals The number of digits after the decimal point for the receiving currency. For example,
+     *     USD has 2 decimal places. This should align with the `decimals` field returned for the chosen currency in the
+     *     LNURLP response.
      * @param conversionRate The conversion rate. It is the numer of milli-satoshis per the smallest unit of the
      *     specified currency (for example: cents in USD). This rate is committed to by the receiving VASP until the
      *     invoice expires.
@@ -468,6 +481,7 @@ class UmaProtocolHelper @JvmOverloads constructor(
         invoiceCreator: UmaInvoiceCreator,
         metadata: String,
         currencyCode: String,
+        currencyDecimals: Int,
         conversionRate: Double,
         receiverFeesMillisats: Long,
         receiverChannelUtxos: List<String>,
@@ -489,6 +503,7 @@ class UmaProtocolHelper @JvmOverloads constructor(
             ),
             paymentInfo = PayReqResponsePaymentInfo(
                 currencyCode = currencyCode,
+                decimals = currencyDecimals,
                 multiplier = conversionRate,
                 exchangeFeesMillisatoshi = receiverFeesMillisats,
             ),

uma-sdk/src/commonMain/kotlin/me/uma/Version.kt

@@ -6,7 +6,7 @@ import kotlinx.serialization.json.encodeToJsonElement
 import kotlinx.serialization.json.put
 
 const val MAJOR_VERSION = 0
-const val MINOR_VERSION = 2
+const val MINOR_VERSION = 3
 const val UMA_VERSION_STRING = "$MAJOR_VERSION.$MINOR_VERSION"
 
 /**

uma-sdk/src/commonMain/kotlin/me/uma/protocol/PayReqResponse.kt

@@ -59,6 +59,11 @@ data class PayReqResponseCompliance(
  * The payment info from the receiver.
  *
  * @property currencyCode The currency code that the receiver will receive for this payment.
+ * @property decimals Number of digits after the decimal point for the receiving currency. For example, in USD, by
+ *     convention, there are 2 digits for cents - $5.95. In this case, `decimals` would be 2. This should align with
+ *     the currency's `decimals` field in the LNURLP response. It is included here for convenience. See
+ *     [UMAD-04](https://github.com/uma-universal-money-address/protocol/blob/main/umad-04-lnurlp-response.md) for
+ *     details, edge cases, and examples.
  * @property multiplier The conversion rate. It is the number of millisatoshis that the receiver will receive for 1
  *     unit of the specified currency (eg: cents in USD). In this context, this is just for convenience. The conversion
  *     rate is also baked into the invoice amount itself. Specifically:
@@ -69,6 +74,7 @@ data class PayReqResponseCompliance(
 @Serializable
 data class PayReqResponsePaymentInfo(
     val currencyCode: String,
+    val decimals: Int,
     val multiplier: Double,
     val exchangeFeesMillisatoshi: Long,
 )