feat: add knowledge module caching layer (closes #79)

apps/api/src/knowledge/services/search.service.ts

@@ -5,6 +5,7 @@ import type {
   KnowledgeEntryWithTags,
   PaginatedEntries,
 } from "../entities/knowledge-entry.entity";
+import { KnowledgeCacheService } from "./cache.service";
 
 /**
  * Search options for full-text search
@@ -63,7 +64,10 @@ interface RawSearchResult {
  */
 @Injectable()
 export class SearchService {
-  constructor(private readonly prisma: PrismaService) {}
+  constructor(
+    private readonly prisma: PrismaService,
+    private readonly cache: KnowledgeCacheService
+  ) {}
 
   /**
    * Full-text search on title and content using PostgreSQL ts_vector
@@ -98,6 +102,13 @@ export class SearchService {
       };
     }
 
+    // Check cache first
+    const filters = { status: options.status, page, limit };
+    const cached = await this.cache.getSearch(workspaceId, sanitizedQuery, filters);
+    if (cached) {
+      return cached;
+    }
+
     // Build status filter
     const statusFilter = options.status
       ? Prisma.sql`AND e.status = ${options.status}::text::"EntryStatus"`
@@ -184,7 +195,7 @@ export class SearchService {
       tags: tagsMap.get(row.id) || [],
     }));
 
-    return {
+    const result = {
       data,
       pagination: {
         page,
@@ -194,6 +205,11 @@ export class SearchService {
       },
       query,
     };
+
+    // Cache the result
+    await this.cache.setSearch(workspaceId, sanitizedQuery, filters, result);
+
+    return result;
   }
 
   /**