feat: toggle availability of reverse swaps (#80)

lib/consts/Enums.ts

@@ -19,3 +19,7 @@ export enum SwapUpdateEvent {
   TransactionRefunded = 'transaction.refunded',
   TransactionConfirmed = 'transaction.confirmed',
 }
+
+export enum ServiceWarning {
+  ReverseSwapsDisabled = 'reverse.swaps.disabled',
+}

lib/notifications/CommandHandler.ts

@@ -7,11 +7,13 @@ import { SwapInstance, ReverseSwapInstance, Swap } from '../consts/Database';
 import { satoshisToCoins, parseBalances, getFeeSymbol, stringify, getSuccessfulTrades } from '../Utils';
 
 enum Command {
-  GetBalance = 'getbalance',
+  Help = 'help',
+
   GetFees = 'getfees',
   SwapInfo = 'swapinfo',
+  GetBalance = 'getbalance',
   NewAddress = 'newaddress',
-  Help = 'help',
+  ToggleReverseSwaps = 'togglereverse',
 }
 
 type CommandInfo = {
@@ -29,11 +31,13 @@ class CommandHandler {
     private discord: DiscordClient) {
 
     this.commands = new Map<string, CommandInfo>([
-      [Command.GetBalance, { description: 'gets the balance of the wallet and channels', executor: this.getBalance }],
+      [Command.Help, { description: 'gets a list of all available commands', executor: this.help }],
+
       [Command.GetFees, { description: 'gets the accumulated fees', executor: this.getFees }],
-      [Command.SwapInfo, { description: 'gets all available information about a (reverse) swap', executor: this.swapInfo }],
       [Command.NewAddress, { description: 'generates a new address for a currency', executor: this.newAddress }],
-      [Command.Help, { description: 'gets a list of all available commands', executor: this.help }],
+      [Command.GetBalance, { description: 'gets the balance of the wallet and channels', executor: this.getBalance }],
+      [Command.SwapInfo, { description: 'gets all available information about a (reverse) swap', executor: this.swapInfo }],
+      [Command.ToggleReverseSwaps, { description: 'enables or disables reverse swaps', executor: this.toggleReverseSwaps }],
     ]);
 
     this.discord.on('message', async (message: string) => {
@@ -147,6 +151,12 @@ class CommandHandler {
     }
   }
 
+  private toggleReverseSwaps = async () => {
+    this.service.allowReverseSwaps = !this.service.allowReverseSwaps;
+
+    await this.discord.sendMessage(`${this.service.allowReverseSwaps ? 'Enabled' : 'Disabled'} reverse swaps`);
+  }
+
   private help = async () => {
     let message = 'Commands:\n';
 

lib/service/Errors.ts

@@ -27,4 +27,8 @@ export default {
     message: 'a swap with this invoice exists already',
     code: concatErrorCode(ErrorCodePrefix.Service, 5),
   }),
+  REVERSE_SWAPS_DISABLED: (): Error => ({
+    message: 'reverse swaps are disabled',
+    code: concatErrorCode(ErrorCodePrefix.Service, 6),
+  }),
 };

lib/service/Service.ts

@@ -8,13 +8,13 @@ import PairRepository from './PairRepository';
 import BoltzClient from '../boltz/BoltzClient';
 import FeeProvider from '../rates/FeeProvider';
 import RateProvider from '../rates/RateProvider';
-import { SwapUpdateEvent } from '../consts/Enums';
+import { SwapUpdateEvent, ServiceWarning } from '../consts/Enums';
 import { encodeBip21 } from './PaymentRequestUtils';
 import ReverseSwapRepository from './ReverseSwapRepository';
 import { SwapUpdate, CurrencyConfig, PairConfig } from '../consts/Types';
 import { OrderSide, OutputType, CurrencyInfo } from '../proto/boltzrpc_pb';
-import { PairInstance, PairFactory, SwapInstance, ReverseSwapInstance } from '../consts/Database';
 import { splitPairId, stringify, generateId, mapToObject, feeMapToObject } from '../Utils';
+import { PairInstance, PairFactory, SwapInstance, ReverseSwapInstance } from '../consts/Database';
 
 type Pair = {
   id: string;
@@ -31,6 +31,8 @@ interface Service {
 }
 
 class Service extends EventEmitter {
+  public allowReverseSwaps = true;
+
   public swapRepository: SwapRepository;
   public reverseSwapRepository: ReverseSwapRepository;
 
@@ -154,7 +156,16 @@ class Service extends EventEmitter {
    * Gets all supported pairs and their conversion rates
    */
   public getPairs = () => {
-    return mapToObject(this.rateProvider.pairs);
+    const warnings: ServiceWarning[] = [];
+
+    if (!this.allowReverseSwaps) {
+      warnings.push(ServiceWarning.ReverseSwapsDisabled);
+    }
+
+    return {
+      warnings,
+      pairs: mapToObject(this.rateProvider.pairs),
+    };
   }
 
   /**
@@ -240,6 +251,10 @@ class Service extends EventEmitter {
    * Creates a new reverse Swap from Lightning to the chain
    */
   public createReverseSwap = async (pairId: string, orderSide: string, claimPublicKey: string, amount: number) => {
+    if (!this.allowReverseSwaps) {
+      throw Errors.REVERSE_SWAPS_DISABLED();
+    }
+
     const { base, quote, rate } = this.getPair(pairId);
 
     const side = this.getOrderSide(orderSide);