Block on tx-fee-request in core TakeOfferModel init

core/src/main/java/bisq/core/offer/takeoffer/TakeOfferModel.java

@@ -1,3 +1,20 @@
+/*
+ * This file is part of Bisq.
+ *
+ * Bisq is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or (at
+ * your option) any later version.
+ *
+ * Bisq is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU Affero General Public
+ * License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with Bisq. If not, see <http://www.gnu.org/licenses/>.
+ */
+
 package bisq.core.offer.takeoffer;
 
 import bisq.core.account.witness.AccountAgeWitnessService;
@@ -20,6 +37,8 @@
 import javax.inject.Inject;
 
 import java.util.Objects;
+import java.util.concurrent.CompletableFuture;
+import java.util.concurrent.ExecutionException;
 
 import lombok.Getter;
 import lombok.extern.slf4j.Slf4j;
@@ -141,12 +160,19 @@ private void calculateTxFees() {
         // Payout tx: 371 bytes
         // Disputed payout tx: 408 bytes
 
-        // Request actual fees:
-        log.info("Start requestTxFee: txFeeFromFeeService={}", txFeeFromFeeService);
-        feeService.requestFees(() -> {
-            txFeePerByteFromFeeService = feeService.getTxFeePerByte();
-            txFeeFromFeeService = offerUtil.getTxFeeBySize(txFeePerByteFromFeeService, feeTxSize);
-        });
+        txFeePerByteFromFeeService = getTxFeePerByte();
+        txFeeFromFeeService = offerUtil.getTxFeeBySize(txFeePerByteFromFeeService, feeTxSize);
+        log.info("{} txFeePerByte = {}", feeService.getClass().getSimpleName(), txFeePerByteFromFeeService);
+    }
+
+    private Coin getTxFeePerByte() {
+        try {
+            CompletableFuture<Void> feeRequestFuture = CompletableFuture.runAsync(feeService::requestFees);
+            feeRequestFuture.get();  // Block until async fee request is complete.
+            return feeService.getTxFeePerByte();
+        } catch (InterruptedException | ExecutionException e) {
+            throw new IllegalStateException("Could not request fees from fee service.", e);
+        }
     }
 
     private void calculateTotalToPay() {