Add counterparty option to getTransactions

src/api/common/schemas/transactions-options.json

@@ -15,6 +15,7 @@
     "excludeFailures": {"type": "boolean"},
     "outgoing": {"type": "boolean"},
     "incoming": {"type": "boolean"},
+    "counterparty": {"$ref": "address"},
     "types": {
       "type": "array",
       "items": {

src/api/ledger/transactions.js

@@ -27,6 +27,10 @@ function transactionFilter(address, filters, tx) {
   if (filters.incoming && tx.address === address) {
     return false;
   }
+  if (filters.counterparty && tx.address !== filters.counterparty
+      && tx.Destination !== filters.counterparty) {
+    return false;
+  }
   return true;
 }