wallet-core/packages/taler-wallet-core/src/operations/balance.ts

534 lines
16 KiB
TypeScript

/*
This file is part of GNU Taler
(C) 2019 GNUnet e.V.
GNU Taler is free software; you can redistribute it and/or modify it under the
terms of the GNU General Public License as published by the Free Software
Foundation; either version 3, or (at your option) any later version.
GNU Taler 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 General Public License for more details.
You should have received a copy of the GNU General Public License along with
GNU Taler; see the file COPYING. If not, see <http://www.gnu.org/licenses/>
*/
/**
* Functions to compute the wallet's balance.
*
* There are multiple definition of the wallet's balance.
* We use the following terminology:
*
* - "available": Balance that the wallet believes will certainly be available
* for spending, modulo any failures of the exchange or double spending issues.
* This includes available coins *not* allocated to any
* spending/refresh/... operation. Pending withdrawals are *not* counted
* towards this balance, because they are not certain to succeed.
* Pending refreshes *are* counted towards this balance.
* This balance type is nice to show to the user, because it does not
* temporarily decrease after payment when we are waiting for refreshes
*
* - "material": Balance that the wallet believes it could spend *right now*,
* without waiting for any operations to complete.
* This balance type is important when showing "insufficient balance" error messages.
*
* - "age-acceptable": Subset of the material balance that can be spent
* with age restrictions applied.
*
* - "merchant-acceptable": Subset of the material balance that can be spent with a particular
* merchant (restricted via min age, exchange, auditor, wire_method).
*
* - "merchant-depositable": Subset of the merchant-acceptable balance that the merchant
* can accept via their supported wire methods.
*/
/**
* Imports.
*/
import {
AmountJson,
Amounts,
BalancesResponse,
canonicalizeBaseUrl,
GetBalanceDetailRequest,
Logger,
parsePaytoUri,
ScopeType,
} from "@gnu-taler/taler-util";
import {
AllowedAuditorInfo,
AllowedExchangeInfo,
RefreshGroupRecord,
WalletStoresV1,
} from "../db.js";
import { InternalWalletState } from "../internal-wallet-state.js";
import { checkLogicInvariant } from "../util/invariants.js";
import { GetReadOnlyAccess } from "../util/query.js";
import { getExchangeDetails } from "./exchanges.js";
/**
* Logger.
*/
const logger = new Logger("operations/balance.ts");
interface WalletBalance {
available: AmountJson;
pendingIncoming: AmountJson;
pendingOutgoing: AmountJson;
}
/**
* Compute the available amount that the wallet expects to get
* out of a refresh group.
*/
function computeRefreshGroupAvailableAmount(r: RefreshGroupRecord): AmountJson {
// Don't count finished refreshes, since the refresh already resulted
// in coins being added to the wallet.
let available = Amounts.zeroOfCurrency(r.currency);
if (r.timestampFinished) {
return available;
}
for (let i = 0; i < r.oldCoinPubs.length; i++) {
const session = r.refreshSessionPerCoin[i];
if (session) {
// We are always assuming the refresh will succeed, thus we
// report the output as available balance.
available = Amounts.add(available, session.amountRefreshOutput).amount;
} else {
available = Amounts.add(available, r.estimatedOutputPerCoin[i]).amount;
}
}
return available;
}
/**
* Get balance information.
*/
export async function getBalancesInsideTransaction(
ws: InternalWalletState,
tx: GetReadOnlyAccess<{
coins: typeof WalletStoresV1.coins;
coinAvailability: typeof WalletStoresV1.coinAvailability;
refreshGroups: typeof WalletStoresV1.refreshGroups;
withdrawalGroups: typeof WalletStoresV1.withdrawalGroups;
}>,
): Promise<BalancesResponse> {
const balanceStore: Record<string, WalletBalance> = {};
/**
* Add amount to a balance field, both for
* the slicing by exchange and currency.
*/
const initBalance = (currency: string): WalletBalance => {
const b = balanceStore[currency];
if (!b) {
balanceStore[currency] = {
available: Amounts.zeroOfCurrency(currency),
pendingIncoming: Amounts.zeroOfCurrency(currency),
pendingOutgoing: Amounts.zeroOfCurrency(currency),
};
}
return balanceStore[currency];
};
await tx.coinAvailability.iter().forEach((ca) => {
const b = initBalance(ca.currency);
for (let i = 0; i < ca.freshCoinCount; i++) {
b.available = Amounts.add(b.available, {
currency: ca.currency,
fraction: ca.amountFrac,
value: ca.amountVal,
}).amount;
}
});
await tx.refreshGroups.iter().forEach((r) => {
const b = initBalance(r.currency);
b.available = Amounts.add(
b.available,
computeRefreshGroupAvailableAmount(r),
).amount;
});
await tx.withdrawalGroups.iter().forEach((wds) => {
if (wds.timestampFinish) {
return;
}
const b = initBalance(Amounts.currencyOf(wds.denomsSel.totalWithdrawCost));
b.pendingIncoming = Amounts.add(
b.pendingIncoming,
wds.denomsSel.totalCoinValue,
).amount;
});
const balancesResponse: BalancesResponse = {
balances: [],
};
Object.keys(balanceStore)
.sort()
.forEach((c) => {
const v = balanceStore[c];
balancesResponse.balances.push({
scopeInfo: {
type: ScopeType.Global,
currency: Amounts.currencyOf(v.available),
},
available: Amounts.stringify(v.available),
pendingIncoming: Amounts.stringify(v.pendingIncoming),
pendingOutgoing: Amounts.stringify(v.pendingOutgoing),
hasPendingTransactions: false,
requiresUserInput: false,
});
});
return balancesResponse;
}
/**
* Get detailed balance information, sliced by exchange and by currency.
*/
export async function getBalances(
ws: InternalWalletState,
): Promise<BalancesResponse> {
logger.trace("starting to compute balance");
const wbal = await ws.db
.mktx((x) => [
x.coins,
x.coinAvailability,
x.refreshGroups,
x.purchases,
x.withdrawalGroups,
])
.runReadOnly(async (tx) => {
return getBalancesInsideTransaction(ws, tx);
});
logger.trace("finished computing wallet balance");
return wbal;
}
/**
* Information about the balance for a particular payment to a particular
* merchant.
*/
export interface MerchantPaymentBalanceDetails {
balanceAvailable: AmountJson;
}
export interface MerchantPaymentRestrictionsForBalance {
currency: string;
minAge: number;
acceptedExchanges: AllowedExchangeInfo[];
acceptedAuditors: AllowedAuditorInfo[];
acceptedWireMethods: string[];
}
export interface AcceptableExchanges {
/**
* Exchanges accepted by the merchant, but wire method might not match.
*/
acceptableExchanges: string[];
/**
* Exchanges accepted by the merchant, including a matching
* wire method, i.e. the merchant can deposit coins there.
*/
depositableExchanges: string[];
}
/**
* Get all exchanges that are acceptable for a particular payment.
*/
export async function getAcceptableExchangeBaseUrls(
ws: InternalWalletState,
req: MerchantPaymentRestrictionsForBalance,
): Promise<AcceptableExchanges> {
const acceptableExchangeUrls = new Set<string>();
const depositableExchangeUrls = new Set<string>();
await ws.db
.mktx((x) => [x.exchanges, x.exchangeDetails, x.auditorTrust])
.runReadOnly(async (tx) => {
// FIXME: We should have a DB index to look up all exchanges
// for a particular auditor ...
const canonExchanges = new Set<string>();
const canonAuditors = new Set<string>();
for (const exchangeHandle of req.acceptedExchanges) {
const normUrl = canonicalizeBaseUrl(exchangeHandle.exchangeBaseUrl);
canonExchanges.add(normUrl);
}
for (const auditorHandle of req.acceptedAuditors) {
const normUrl = canonicalizeBaseUrl(auditorHandle.auditorBaseUrl);
canonAuditors.add(normUrl);
}
await tx.exchanges.iter().forEachAsync(async (exchange) => {
const dp = exchange.detailsPointer;
if (!dp) {
return;
}
const { currency, masterPublicKey } = dp;
const exchangeDetails = await tx.exchangeDetails.indexes.byPointer.get([
exchange.baseUrl,
currency,
masterPublicKey,
]);
if (!exchangeDetails) {
return;
}
let acceptable = false;
if (canonExchanges.has(exchange.baseUrl)) {
acceptableExchangeUrls.add(exchange.baseUrl);
acceptable = true;
}
for (const exchangeAuditor of exchangeDetails.auditors) {
if (canonAuditors.has(exchangeAuditor.auditor_url)) {
acceptableExchangeUrls.add(exchange.baseUrl);
acceptable = true;
break;
}
}
if (!acceptable) {
return;
}
// FIXME: Also consider exchange and auditor public key
// instead of just base URLs?
let wireMethodSupported = false;
for (const acc of exchangeDetails.wireInfo.accounts) {
const pp = parsePaytoUri(acc.payto_uri);
checkLogicInvariant(!!pp);
for (const wm of req.acceptedWireMethods) {
if (pp.targetType === wm) {
wireMethodSupported = true;
break;
}
if (wireMethodSupported) {
break;
}
}
}
acceptableExchangeUrls.add(exchange.baseUrl);
if (wireMethodSupported) {
depositableExchangeUrls.add(exchange.baseUrl);
}
});
});
return {
acceptableExchanges: [...acceptableExchangeUrls],
depositableExchanges: [...depositableExchangeUrls],
};
}
export interface MerchantPaymentBalanceDetails {
/**
* Balance of type "available" (see balance.ts for definition).
*/
balanceAvailable: AmountJson;
/**
* Balance of type "material" (see balance.ts for definition).
*/
balanceMaterial: AmountJson;
/**
* Balance of type "age-acceptable" (see balance.ts for definition).
*/
balanceAgeAcceptable: AmountJson;
/**
* Balance of type "merchant-acceptable" (see balance.ts for definition).
*/
balanceMerchantAcceptable: AmountJson;
/**
* Balance of type "merchant-depositable" (see balance.ts for definition).
*/
balanceMerchantDepositable: AmountJson;
}
export async function getMerchantPaymentBalanceDetails(
ws: InternalWalletState,
req: MerchantPaymentRestrictionsForBalance,
): Promise<MerchantPaymentBalanceDetails> {
const acceptability = await getAcceptableExchangeBaseUrls(ws, req);
const d: MerchantPaymentBalanceDetails = {
balanceAvailable: Amounts.zeroOfCurrency(req.currency),
balanceMaterial: Amounts.zeroOfCurrency(req.currency),
balanceAgeAcceptable: Amounts.zeroOfCurrency(req.currency),
balanceMerchantAcceptable: Amounts.zeroOfCurrency(req.currency),
balanceMerchantDepositable: Amounts.zeroOfCurrency(req.currency),
};
await ws.db
.mktx((x) => [
x.coins,
x.coinAvailability,
x.refreshGroups,
x.purchases,
x.withdrawalGroups,
])
.runReadOnly(async (tx) => {
await tx.coinAvailability.iter().forEach((ca) => {
if (ca.currency != req.currency) {
return;
}
const singleCoinAmount: AmountJson = {
currency: ca.currency,
fraction: ca.amountFrac,
value: ca.amountVal,
};
const coinAmount: AmountJson = Amounts.mult(
singleCoinAmount,
ca.freshCoinCount,
).amount;
d.balanceAvailable = Amounts.add(d.balanceAvailable, coinAmount).amount;
d.balanceMaterial = Amounts.add(d.balanceMaterial, coinAmount).amount;
if (ca.maxAge === 0 || ca.maxAge > req.minAge) {
d.balanceAgeAcceptable = Amounts.add(
d.balanceAgeAcceptable,
coinAmount,
).amount;
if (acceptability.acceptableExchanges.includes(ca.exchangeBaseUrl)) {
d.balanceMerchantAcceptable = Amounts.add(
d.balanceMerchantAcceptable,
coinAmount,
).amount;
if (
acceptability.depositableExchanges.includes(ca.exchangeBaseUrl)
) {
d.balanceMerchantDepositable = Amounts.add(
d.balanceMerchantDepositable,
coinAmount,
).amount;
}
}
}
});
await tx.refreshGroups.iter().forEach((r) => {
if (r.currency != req.currency) {
return;
}
d.balanceAvailable = Amounts.add(
d.balanceAvailable,
computeRefreshGroupAvailableAmount(r),
).amount;
});
});
return d;
}
export async function getBalanceDetail(
ws: InternalWalletState,
req: GetBalanceDetailRequest,
): Promise<MerchantPaymentBalanceDetails> {
const exchanges: { exchangeBaseUrl: string; exchangePub: string }[] = [];
const wires = new Array<string>();
await ws.db
.mktx((x) => [x.exchanges, x.exchangeDetails])
.runReadOnly(async (tx) => {
const allExchanges = await tx.exchanges.iter().toArray();
for (const e of allExchanges) {
const details = await getExchangeDetails(tx, e.baseUrl);
if (!details || req.currency !== details.currency) {
continue;
}
details.wireInfo.accounts.forEach((a) => {
const payto = parsePaytoUri(a.payto_uri);
if (payto && !wires.includes(payto.targetType)) {
wires.push(payto.targetType);
}
});
exchanges.push({
exchangePub: details.masterPublicKey,
exchangeBaseUrl: e.baseUrl,
});
}
});
return await getMerchantPaymentBalanceDetails(ws, {
currency: req.currency,
acceptedAuditors: [],
acceptedExchanges: exchanges,
acceptedWireMethods: wires,
minAge: 0,
});
}
export interface PeerPaymentRestrictionsForBalance {
currency: string;
restrictExchangeTo?: string;
}
export interface PeerPaymentBalanceDetails {
/**
* Balance of type "available" (see balance.ts for definition).
*/
balanceAvailable: AmountJson;
/**
* Balance of type "material" (see balance.ts for definition).
*/
balanceMaterial: AmountJson;
}
export async function getPeerPaymentBalanceDetailsInTx(
ws: InternalWalletState,
tx: GetReadOnlyAccess<{
coinAvailability: typeof WalletStoresV1.coinAvailability;
refreshGroups: typeof WalletStoresV1.refreshGroups;
}>,
req: PeerPaymentRestrictionsForBalance,
): Promise<PeerPaymentBalanceDetails> {
let balanceAvailable = Amounts.zeroOfCurrency(req.currency);
let balanceMaterial = Amounts.zeroOfCurrency(req.currency);
await tx.coinAvailability.iter().forEach((ca) => {
if (ca.currency != req.currency) {
return;
}
if (
req.restrictExchangeTo &&
req.restrictExchangeTo !== ca.exchangeBaseUrl
) {
return;
}
const singleCoinAmount: AmountJson = {
currency: ca.currency,
fraction: ca.amountFrac,
value: ca.amountVal,
};
const coinAmount: AmountJson = Amounts.mult(
singleCoinAmount,
ca.freshCoinCount,
).amount;
balanceAvailable = Amounts.add(balanceAvailable, coinAmount).amount;
balanceMaterial = Amounts.add(balanceMaterial, coinAmount).amount;
});
await tx.refreshGroups.iter().forEach((r) => {
balanceAvailable = Amounts.add(
balanceAvailable,
computeRefreshGroupAvailableAmount(r),
).amount;
});
return {
balanceAvailable,
balanceMaterial,
};
}