feat(core): Integrate tracing into ConfigService for enhanced custom fields logging

packages/core/src/config/config.service.ts

@@ -1,5 +1,6 @@
 import { DynamicModule, Injectable, Type } from '@nestjs/common';
 import { LanguageCode } from '@vendure/common/lib/generated-types';
+import { Span, TraceService } from 'nestjs-otel';
 import { DataSourceOptions, getMetadataArgsStorage } from 'typeorm';
 
 import { getConfig } from './config-helpers';
@@ -29,7 +30,7 @@ export class ConfigService implements VendureConfig {
     private activeConfig: RuntimeVendureConfig;
     private allCustomFieldsConfig: Required<CustomFields> | undefined;
 
-    constructor() {
+    constructor(private readonly traceService: TraceService) {
         this.activeConfig = getConfig();
         if (this.activeConfig.authOptions.disableAuth) {
             // eslint-disable-next-line
@@ -120,9 +121,12 @@ export class ConfigService implements VendureConfig {
         return this.activeConfig.systemOptions;
     }
 
+    @Span('vendure.config.get-custom-fields-for-all-entities')
     private getCustomFieldsForAllEntities(): Required<CustomFields> {
         const definedCustomFields = this.activeConfig.customFields;
         const metadataArgsStorage = getMetadataArgsStorage();
+        const span = this.traceService.getSpan();
+        span?.setAttribute('customFields', JSON.stringify(definedCustomFields));
         // We need to check for any entities which have a "customFields" property but which are not
         // explicitly defined in the customFields config. This is because the customFields object
         // only includes the built-in entities. Any custom entities which have a "customFields"
@@ -140,10 +144,12 @@ export class ConfigService implements VendureConfig {
                             .find(c => c.propertyName === 'languageCode');
                     if (hasCustomFields && !isTranslationEntity) {
                         definedCustomFields[entity.name] = [];
+                        span?.addEvent('removed-custom-fields', { entity: entity.name });
                     }
                 }
             }
         }
+        span?.end();
         return definedCustomFields;
     }