convert existing xrpl library into a lerna monorepo

packages/xrpl/src/utils/signPaymentChannelClaim.ts

@@ -0,0 +1,27 @@
+import binary from 'ripple-binary-codec'
+import keypairs from 'ripple-keypairs'
+
+import { xrpToDrops } from './xrpConversion'
+
+/**
+ * Sign a payment channel claim.
+ *
+ * @param channel - Channel identifier specified by the paymentChannelClaim.
+ * @param amount - Amount specified by the paymentChannelClaim.
+ * @param privateKey - Private Key to sign paymentChannelClaim with.
+ * @returns True if the channel is valid.
+ * @category Utilities
+ */
+function signPaymentChannelClaim(
+  channel: string,
+  amount: string,
+  privateKey: string,
+): string {
+  const signingData = binary.encodeForSigningClaim({
+    channel,
+    amount: xrpToDrops(amount),
+  })
+  return keypairs.sign(signingData, privateKey)
+}
+
+export default signPaymentChannelClaim