phase-8f: persistant cache locally

server/clients/YahooFinanceClient.ts

@@ -11,10 +11,16 @@ export class YahooFinanceClient {
     });
   }
 
+  /** Normalise ticker before hitting Yahoo: BRK.B → BRK-B */
+  private static normalise(ticker: string): string {
+    return ticker.toUpperCase().replace(/\./g, '-');
+  }
+
   async fetchSummary(ticker: string, retries = 3, backoff = 1000): Promise<any> {
+    const normalised = YahooFinanceClient.normalise(ticker);
     for (let attempt = 0; attempt < retries; attempt++) {
       try {
-        return await this.lib.quoteSummary(ticker, { modules: YAHOO_MODULES });
+        return await this.lib.quoteSummary(normalised, { modules: YAHOO_MODULES });
       } catch (error) {
         if (attempt === retries - 1) throw error;
         await new Promise<void>((resolve) => setTimeout(resolve, backoff * (attempt + 1)));
@@ -24,7 +30,9 @@ export class YahooFinanceClient {
 
   async fetchCalendarEvents(ticker: string): Promise<any | null> {
     try {
-      const result = await this.lib.quoteSummary(ticker, { modules: ['calendarEvents'] });
+      const result = await this.lib.quoteSummary(YahooFinanceClient.normalise(ticker), {
+        modules: ['calendarEvents'],
+      });
       return result.calendarEvents ?? null;
     } catch {
       return null;

server/controllers/finance.controller.ts

@@ -13,10 +13,6 @@ export class FinanceController {
     private readonly advisor: PortfolioAdvisor,
   ) {}
 
-  private static normalizeYahoo(ticker: string): string {
-    return ticker.toUpperCase().replace(/\./g, '-');
-  }
-
   register(app: FastifyInstance): void {
     app.get('/api/finance/portfolio', this.portfolio.bind(this));
     app.post('/api/finance/holdings', { schema: holdingSchema }, this.addHolding.bind(this));
@@ -38,7 +34,7 @@ export class FinanceController {
 
     const screenable = holdings
       .filter((h) => (h.type ?? 'stock') !== 'crypto')
-      .map((h) => FinanceController.normalizeYahoo(h.ticker));
+      .map((h) => h.ticker.toUpperCase());
 
     const results =
       screenable.length > 0

server/services/BenchmarkProvider.ts

@@ -1,9 +1,16 @@
+import { readFileSync, writeFileSync, existsSync } from 'fs';
 import { YahooFinanceClient } from '../clients/YahooFinanceClient';
 import { REGIME } from '../config/constants';
 import type { MarketContext, Logger, BenchmarkProviderOptions } from '../types';
 
+interface CacheFile {
+  data: MarketContext;
+  expiresAt: number;
+}
+
 export class BenchmarkProvider {
   private static readonly TTL_MS = 60 * 60 * 1000;
+  private static readonly CACHE_PATH = '.benchmark-cache.json';
 
   private static readonly DEFAULTS: MarketContext = {
     sp500Price: 5000,
@@ -32,10 +39,33 @@ export class BenchmarkProvider {
     private readonly client: YahooFinanceClient,
     { logger }: BenchmarkProviderOptions = {},
   ) {
-    this.cache = { data: null, expiresAt: 0 };
+    this.cache = this.loadDiskCache();
     this.logger = logger ?? (console as unknown as Logger);
   }
 
+  private loadDiskCache(): { data: MarketContext | null; expiresAt: number } {
+    try {
+      if (!existsSync(BenchmarkProvider.CACHE_PATH)) return { data: null, expiresAt: 0 };
+      const file = JSON.parse(readFileSync(BenchmarkProvider.CACHE_PATH, 'utf8')) as CacheFile;
+      if (Date.now() < file.expiresAt) return { data: file.data, expiresAt: file.expiresAt };
+    } catch {
+      // corrupt or missing — ignore
+    }
+    return { data: null, expiresAt: 0 };
+  }
+
+  private saveDiskCache(data: MarketContext, expiresAt: number): void {
+    try {
+      writeFileSync(
+        BenchmarkProvider.CACHE_PATH,
+        JSON.stringify({ data, expiresAt } satisfies CacheFile, null, 2),
+        'utf8',
+      );
+    } catch {
+      // non-fatal — in-memory cache still works
+    }
+  }
+
   async getMarketContext(): Promise<MarketContext> {
     if (this.cache.data && Date.now() < this.cache.expiresAt) return this.cache.data;
 
@@ -75,7 +105,9 @@ export class BenchmarkProvider {
         },
       };
 
-      this.cache = { data: context, expiresAt: Date.now() + BenchmarkProvider.TTL_MS };
+      const expiresAt = Date.now() + BenchmarkProvider.TTL_MS;
+      this.cache = { data: context, expiresAt };
+      this.saveDiskCache(context, expiresAt);
       return context;
     } catch (err) {
       this.logger.warn('Market data fetch failed, using defaults:', (err as Error).message);