Add MEXC Assessment Zone trading pair support

src/integration/exchange/services/exchange.service.ts

@@ -43,7 +43,7 @@ export abstract class ExchangeService extends PricingProvider implements OnModul
   protected abstract readonly networks: { [b in Blockchain]: string | false };
   protected readonly exchange: Exchange;
 
-  private markets: Market[];
+  protected markets: Market[];
 
   @Inject() private readonly registry: ExchangeRegistryService;
 
@@ -225,7 +225,7 @@ export abstract class ExchangeService extends PricingProvider implements OnModul
 
   // --- Helper Methods --- //
   // currency pairs
-  private async getMarkets(): Promise<Market[]> {
+  protected async getMarkets(): Promise<Market[]> {
     if (!this.markets) {
       this.markets = await this.callApi((e) => e.fetchMarkets());
     }

src/integration/exchange/services/mexc.service.ts

@@ -1,6 +1,6 @@
 import { Injectable } from '@nestjs/common';
 import { Method } from 'axios';
-import { mexc, Transaction } from 'ccxt';
+import { Market, mexc, Transaction } from 'ccxt';
 import { Config, GetConfig } from 'src/config/config';
 import { Blockchain } from 'src/integration/blockchain/shared/enums/blockchain.enum';
 import { DfxLogger } from 'src/shared/services/dfx-logger';
@@ -49,6 +49,33 @@ export class MexcService extends ExchangeService {
     Yapeal: undefined,
   };
 
+  // Assessment Zone pairs - require API whitelisting from MEXC
+  // See: https://www.mexc.com/announcements/article/api-access-changes-for-assessment-zone-trading-pairs-17827791522788
+  private readonly assessmentZonePairs: Partial<Market>[] = [
+    {
+      id: 'ZCHFUSDT',
+      symbol: 'ZCHF/USDT',
+      base: 'ZCHF',
+      quote: 'USDT',
+      baseId: 'ZCHF',
+      quoteId: 'USDT',
+      active: true,
+      type: 'spot',
+      spot: true,
+      margin: false,
+      future: false,
+      swap: false,
+      option: false,
+      contract: false,
+      limits: {
+        amount: { min: 1, max: undefined },
+        price: { min: 0.0001, max: undefined },
+        cost: { min: 1, max: undefined },
+      },
+      precision: { amount: 2, price: 4 },
+    },
+  ];
+
   constructor(private readonly http: HttpService) {
     super(mexc, GetConfig().mexc);
   }
@@ -59,6 +86,30 @@ export class MexcService extends ExchangeService {
     return 'MEXC';
   }
 
+  protected async getMarkets(): Promise<Market[]> {
+    const markets = await super.getMarkets();
+
+    // Inject Assessment Zone pairs that are hidden from public API
+    for (const azPair of this.assessmentZonePairs) {
+      if (!markets.find((m) => m.symbol === azPair.symbol)) {
+        markets.push(azPair as Market);
+
+        // Also inject into ccxt's internal caches for methods like fetchOrderBook/createOrder
+        if (this.exchange.markets && !this.exchange.markets[azPair.symbol]) {
+          this.exchange.markets[azPair.symbol] = azPair as Market;
+        }
+        if (this.exchange.markets_by_id && azPair.id && !this.exchange.markets_by_id[azPair.id]) {
+          this.exchange.markets_by_id[azPair.id] = azPair as Market;
+        }
+        if (this.exchange.symbols && !this.exchange.symbols.includes(azPair.symbol)) {
+          this.exchange.symbols.push(azPair.symbol);
+        }
+      }
+    }
+
+    return markets;
+  }
+
   async getDeposits(token: string, from: Date): Promise<Transaction[]> {
     const startTime = from.getTime().toString();
     const endTime = new Date().getTime().toString();