backend/btc: do not panic when retrieving balance

Similar to 52da637, where the same as
done for the transactions list.

Fixes one panic TODO. All call sites deal with the error now. An error
here is usually a database access for a database that was already
closed (e.g. transactions endpoint called at the same time as a
bitbox02 is unplugged or the account is closed for some other reason).

backend/coins/btc/account.go

@@ -544,12 +544,7 @@ func (account *Account) Balance() (*accounts.Balance, error) {
 	if account.fatalError.Load() {
 		return nil, errp.New("can't call Balance() after a fatal error")
 	}
-	balance, err := account.transactions.Balance()
-	if err != nil {
-		// TODO
-		panic(err)
-	}
-	return balance, nil
+	return account.transactions.Balance()
 }
 
 func (account *Account) incAndEmitSyncCounter() {

backend/coins/btc/handlers/handlers.go

@@ -326,16 +326,24 @@ func (handlers *Handlers) getUTXOs(_ *http.Request) (interface{}, error) {
 }
 
 func (handlers *Handlers) getAccountBalance(_ *http.Request) (interface{}, error) {
+	var result struct {
+		Success      bool            `json:"success"`
+		HasAvailable bool            `json:"hasAvailable"`
+		Available    FormattedAmount `json:"available"`
+		HasIncoming  bool            `json:"hasIncoming"`
+		Incoming     FormattedAmount `json:"incoming"`
+	}
 	balance, err := handlers.account.Balance()
 	if err != nil {
-		return nil, err
+		handlers.log.WithError(err).Error("Error getting account balance")
+		return result, nil
 	}
-	return map[string]interface{}{
-		"hasAvailable": balance.Available().BigInt().Sign() > 0,
-		"available":    handlers.formatAmountAsJSON(balance.Available(), false),
-		"hasIncoming":  balance.Incoming().BigInt().Sign() > 0,
-		"incoming":     handlers.formatAmountAsJSON(balance.Incoming(), false),
-	}, nil
+	result.Success = true
+	result.HasAvailable = balance.Available().BigInt().Sign() > 0
+	result.Available = handlers.formatAmountAsJSON(balance.Available(), false)
+	result.HasIncoming = balance.Incoming().BigInt().Sign() > 0
+	result.Incoming = handlers.formatAmountAsJSON(balance.Incoming(), false)
+	return result, nil
 }
 
 type sendTxInput struct {

frontends/web/src/api/account.ts

@@ -15,6 +15,7 @@
  */
 
 import { apiGet, apiPost } from '../utils/request';
+import { SuccessResponse } from './response';
 import { ChartData } from '../routes/account/summary/chart';
 
 export type CoinCode = 'btc' | 'tbtc' | 'ltc' | 'tltc' | 'eth' | 'goeth';
@@ -151,7 +152,9 @@ export interface IBalance {
     incoming: IAmount;
 }
 
-export const getBalance = (code: AccountCode): Promise<IBalance> => {
+export type TBalanceResult = { success: false } | (SuccessResponse & IBalance);
+
+export const getBalance = (code: AccountCode): Promise<TBalanceResult> => {
   return apiGet(`account/${code}/balance`);
 };
 

frontends/web/src/components/balance/balance.test.tsx

@@ -15,13 +15,14 @@
  */
 
 import { render } from '@testing-library/react';
-import { IBalance } from '../../api/account';
+import { TBalanceResult } from '../../api/account';
 import I18NWrapper from '../../i18n/forTests/i18nwrapper';
 import { Balance } from './balance';
 
 describe('components/balance/balance', () => {
   it('renders balance properly', () => {
-    const MOCK_BALANCE: IBalance = {
+    const MOCK_BALANCE: TBalanceResult = {
+      success: true,
       hasAvailable: true,
       hasIncoming: true,
       available: {

frontends/web/src/components/balance/balance.tsx

@@ -16,13 +16,13 @@
  */
 
 import { useTranslation } from 'react-i18next';
-import { IBalance } from '../../api/account';
+import { TBalanceResult } from '../../api/account';
 import { FiatConversion } from '../../components/rates/rates';
 import { bitcoinRemoveTrailingZeroes } from '../../utils/trailing-zeroes';
 import style from './balance.module.css';
 
 type TProps = {
-    balance?: IBalance;
+    balance?: TBalanceResult;
     noRotateFiat?: boolean;
 }
 
@@ -36,6 +36,11 @@ export const Balance = ({
       <header className={style.balance}></header>
     );
   }
+  if (!balance.success) {
+    return (
+      <header className={style.balance}>{t('account.balanceError')}</header>
+    );
+  }
 
   // remove trailing zeroes from Bitcoin balance
   const availableBalance = bitcoinRemoveTrailingZeroes(balance.available.amount, balance.available.unit);

frontends/web/src/locales/en/app.json

@@ -8,7 +8,8 @@
     "initializing": "Getting information from the blockchain…",
     "maybeProxyError": "Tor proxy enabled. Ensure that your Tor proxy is running properly, or disable the proxy setting.",
     "reconnecting": "Lost connection, trying to reconnect…",
-    "syncedAddressesCount": "Scanned {{count}} addresses"
+    "syncedAddressesCount": "Scanned {{count}} addresses",
+    "balanceError": "Error retrieving balance"
   },
   "accountInfo": {
     "address": "Address",
@@ -1446,4 +1447,4 @@
     "insertDevice": "Please connect your device to get started",
     "title": "Welcome"
   }
-}
+}

frontends/web/src/routes/account/account.tsx

@@ -54,7 +54,7 @@ export function Account({
 }: Props) {
   const { t } = useTranslation();
 
-  const [balance, setBalance] = useState<accountApi.IBalance>();
+  const [balance, setBalance] = useState<accountApi.TBalanceResult>();
   const [status, setStatus] = useState<accountApi.IStatus>();
   const [syncedAddressesCount, setSyncedAddressesCount] = useState<number>();
   const [transactions, setTransactions] = useState<accountApi.TTransactions>();
@@ -166,7 +166,7 @@ export function Account({
     return null;
   }
 
-  const canSend = balance && balance.hasAvailable;
+  const canSend = balance && balance.success && balance.hasAvailable;
 
   const initializingSpinnerText =
     (syncedAddressesCount !== undefined && syncedAddressesCount > 1) ? (
@@ -188,6 +188,7 @@ export function Account({
   const exchangeBuySupported = supportedExchanges && supportedExchanges.exchanges.length > 0;
 
   const isAccountEmpty = balance
+    && balance.success
     && !balance.hasAvailable
     && !balance.hasIncoming
     && transactions
@@ -265,10 +266,10 @@ export function Account({
       </div>
       <AccountGuide
         account={account}
-        unit={balance?.available.unit}
-        hasIncomingBalance={balance && balance.hasIncoming}
+        unit={balance?.success ? balance?.available.unit : undefined}
+        hasIncomingBalance={balance && balance.success && balance.hasIncoming}
         hasTransactions={transactions !== undefined && transactions.success && transactions.list.length > 0}
-        hasNoBalance={balance && balance.available.amount === '0'} />
+        hasNoBalance={balance && balance.success && balance.available.amount === '0'} />
     </div>
   );
 }

frontends/web/src/routes/account/info/buyReceiveCTA.tsx

@@ -16,14 +16,14 @@
 
 import { useTranslation } from 'react-i18next';
 import { route } from '../../../utils/route';
-import { CoinWithSAT, IBalance } from '../../../api/account';
+import { CoinWithSAT, TBalanceResult } from '../../../api/account';
 import { Button } from '../../../components/forms';
 import { Balances } from '../summary/accountssummary';
 import styles from './buyReceiveCTA.module.css';
 import { isBitcoinCoin } from '../utils';
 
 type TBuyReceiveCTAProps = {
-  balanceList?: [string, IBalance][];
+  balanceList?: [string, TBalanceResult][];
   code?: string;
   unit?: string;
 };
@@ -59,10 +59,10 @@ export const AddBuyReceiveOnEmptyBalances = ({ balances }: {balances?: Balances}
     return null;
   }
   const balanceList = Object.entries(balances);
-  if (balanceList.some(entry => entry[1].hasAvailable)) {
+  if (balanceList.some(entry => entry[1].success && entry[1].hasAvailable)) {
     return null;
   }
-  if (balanceList.map(entry => entry[1].available.unit).every(isBitcoinCoin)) {
+  if (balanceList.every(entry => entry[1].success && isBitcoinCoin(entry[1].available.unit))) {
     return <BuyReceiveCTA code={balanceList[0][0]} unit={'BTC'} balanceList={balanceList} />;
   }
   return <BuyReceiveCTA balanceList={balanceList} />;

frontends/web/src/routes/account/send/send.tsx

@@ -62,7 +62,7 @@ type Props = SendProps & TranslateProps;
 
 interface State {
     account?: accountApi.IAccount;
-    balance?: accountApi.IBalance;
+    balance?: accountApi.TBalanceResult;
     proposedFee?: accountApi.IAmount;
     proposedTotal?: accountApi.IAmount;
     recipientAddress: string;
@@ -680,7 +680,7 @@ class Send extends Component<Props, State> {
                     type="number"
                     step="any"
                     min="0"
-                    label={balance ? balance.available.unit : t('send.amount.label')}
+                    label={balance && balance.success ? balance.available.unit : t('send.amount.label')}
                     id="amount"
                     onInput={this.handleFormChange}
                     disabled={sendAll}

frontends/web/src/routes/account/summary/accountssummary.tsx

@@ -40,7 +40,7 @@ interface AccountSummaryProps {
 }
 
 export interface Balances {
-    [code: string]: accountApi.IBalance;
+    [code: string]: accountApi.TBalanceResult;
 }
 
 interface SyncStatus {
@@ -214,12 +214,17 @@ class AccountsSummary extends Component<Props, State> {
           { nameCol }
           <td data-label={t('accountSummary.balance')}>
             <span className={style.summaryTableBalance}>
-              {balance.available.amount}{' '}
-              <span className={style.coinUnit}>{balance.available.unit}</span>
+              { balance.success ? (
+                <>
+                  {balance.available.amount}{' '}
+                  <span className={style.coinUnit}>{balance.available.unit}</span>
+                </>
+              ) : <>{t('account.balanceError')}</>
+              }
             </span>
           </td>
           <td data-label={t('accountSummary.fiatBalance')}>
-            <FiatConversion amount={balance.available} noAction={true} />
+            { balance.success && <FiatConversion amount={balance.available} noAction={true} /> }
           </td>
         </tr>
       );

frontends/web/src/routes/accounts/select-receive.tsx

@@ -14,7 +14,7 @@
  * limitations under the License.
  */
 
-import { useEffect, useState } from 'react';
+import { useEffect, useState, useCallback } from 'react';
 import { useTranslation } from 'react-i18next';
 import { getBalance, IAccount } from '../../api/account';
 import { AccountSelector, TOption } from '../../components/accountselector/accountselector';
@@ -31,13 +31,26 @@ export const ReceiveAccountsSelector = ({ activeAccounts }: TReceiveAccountsSele
   const [code, setCode] = useState('');
   const { t } = useTranslation();
 
+  const getBalances = useCallback(async (options: TOption[]) => {
+    return Promise.all(options.map((option) => (
+      getBalance(option.value).then(balance => {
+        return {
+          ...option,
+          balance: balance.success ?
+            `${balance.available.amount} ${balance.available.unit}` :
+            t('account.balanceError'),
+        };
+      })
+    )));
+  }, [t]);
+
   useEffect(() => {
     const options = activeAccounts.map(account => ({ label: account.name, value: account.code, disabled: false, coinCode: account.coinCode } as TOption));
     //setting options without balance
     setOptions(options);
     //asynchronously fetching each account's balance
     getBalances(options).then(options => setOptions(options));
-  }, [activeAccounts]);
+  }, [activeAccounts, getBalances]);
 
   const handleProceed = () => {
     route(`/account/${code}/receive`);
@@ -47,14 +60,6 @@ export const ReceiveAccountsSelector = ({ activeAccounts }: TReceiveAccountsSele
 
   const title = t('receive.title', { accountName: hasOnlyBTCAccounts ? 'Bitcoin' : t('buy.info.crypto') });
 
-  const getBalances = async (options: TOption[]) => {
-    return Promise.all(options.map((option) => (
-      getBalance(option.value).then(balance => {
-        return { ...option, balance: `${balance.available.amount} ${balance.available.unit}` };
-      })
-    )));
-  };
-
   return (
     <>
       <Header title={<h2>{title}</h2>} />
@@ -67,4 +72,3 @@ export const ReceiveAccountsSelector = ({ activeAccounts }: TReceiveAccountsSele
 
   );
 };
-

frontends/web/src/routes/buy/info.tsx

@@ -38,6 +38,21 @@ export const BuyInfo = ({ code, accounts }: TProps) => {
 
   const { t } = useTranslation();
 
+  const getBalances = useCallback((options: TOption[]) => {
+    Promise.all(options.map((option) => (
+      getBalance(option.value).then(balance => {
+        return {
+          ...option,
+          balance: balance.success ?
+            `${balance.available.amount} ${balance.available.unit}` :
+            t('account.balanceError'),
+        };
+      })
+    ))).then(options => {
+      setOptions(options);
+    });
+  }, [t]);
+
   const checkSupportedCoins = useCallback(async () => {
     try {
       const accountsWithFalsyValue = await Promise.all(
@@ -56,7 +71,7 @@ export const BuyInfo = ({ code, accounts }: TProps) => {
       console.error(e);
     }
 
-  }, [accounts]);
+  }, [accounts, getBalances]);
 
   const maybeProceed = useCallback(() => {
     if (options !== undefined && options.length === 1) {
@@ -76,17 +91,6 @@ export const BuyInfo = ({ code, accounts }: TProps) => {
     maybeProceed();
   }, [maybeProceed, options]);
 
-
-  const getBalances = (options: TOption[]) => {
-    Promise.all(options.map((option) => (
-      getBalance(option.value).then(balance => {
-        return { ...option, balance: `${balance.available.amount} ${balance.available.unit}` };
-      })
-    ))).then(options => {
-      setOptions(options);
-    });
-  };
-
   const handleProceed = () => {
     route(`/buy/exchange/${selected}`);
   };