feat(corp-filter): ✨ Add filterCorporations and filterUnknownCorpSlugs utility functions and update main.ts integration

Co-Authored-By: Lilith Autocommit <noreply@atlilith.com>

services/api/src/common/corp-filter.util.ts

@@ -14,6 +14,20 @@ import { DataSource } from 'typeorm';
  * is appended. Subquery hits idx_raw_events_corp_id_ts (corp_id leading).
  */
 
+
+/**
+ * Thrown by resolveCorpId when a non-empty slug doesn't match any corp.
+ * Framework-agnostic — mapped to HTTP 400 by UnknownCorpSlugFilter.
+ */
+export class UnknownCorpSlugError extends Error {
+  readonly slug: string;
+  constructor(slug: string) {
+    super(`Unknown corp slug: ${slug}`);
+    this.name = 'UnknownCorpSlugError';
+    this.slug = slug;
+  }
+}
+
 const slugCache = new Map<string, number>();
 
 /**
@@ -44,7 +58,7 @@ export async function resolveCorpId(
   }
 
   if (rows.length === 0) {
-    throw new Error(`Unknown corp slug: ${slug}`);
+    throw new UnknownCorpSlugError(slug);
   }
   const id = Number(rows[0].id);
   slugCache.set(slug, id);

services/api/src/common/unknown-corp-slug.filter.ts

@@ -0,0 +1,19 @@
+import { ArgumentsHost, Catch, ExceptionFilter, HttpStatus } from '@nestjs/common';
+import type { Request, Response } from 'express';
+import { UnknownCorpSlugError } from './corp-filter.util';
+
+@Catch(UnknownCorpSlugError)
+export class UnknownCorpSlugFilter implements ExceptionFilter<UnknownCorpSlugError> {
+  catch(exception: UnknownCorpSlugError, host: ArgumentsHost): void {
+    const ctx = host.switchToHttp();
+    const response = ctx.getResponse<Response>();
+    const request = ctx.getRequest<Request>();
+
+    response.status(HttpStatus.BAD_REQUEST).json({
+      statusCode: HttpStatus.BAD_REQUEST,
+      message: exception.message,
+      error: 'Bad Request',
+      path: request.url,
+    });
+  }
+}

services/api/src/main.ts

@@ -2,11 +2,14 @@ import { NestFactory } from '@nestjs/core';
 import { Logger, ValidationPipe } from '@nestjs/common';
 import { SwaggerModule, DocumentBuilder } from '@nestjs/swagger';
 import { AppModule } from './app.module';
+import { UnknownCorpSlugFilter } from './common/unknown-corp-slug.filter';
 
 async function bootstrap() {
   const logger = new Logger('ApiService');
   const app = await NestFactory.create(AppModule);
 
+  app.useGlobalFilters(new UnknownCorpSlugFilter());
+
   app.useGlobalPipes(
     new ValidationPipe({
       whitelist: true,