feat: allow disabling semantic search

Author: sinedied

infra/main.bicep

@@ -358,7 +358,7 @@ module searchService 'core/search/search-services.bicep' = {
     sku: {
       name: searchServiceSkuName
     }
-    semanticSearch: 'free'
+    semanticSearch: searchServiceSkuName == 'standard' ? 'free' : 'disabled'
   }
 }
 
@@ -526,6 +526,7 @@ output AZURE_OPENAI_EMBEDDING_MODEL string = embeddingModelName
 output AZURE_SEARCH_INDEX string = searchIndexName
 output AZURE_SEARCH_SERVICE string = searchService.outputs.name
 output AZURE_SEARCH_SERVICE_RESOURCE_GROUP string = searchServiceResourceGroup.name
+output AZURE_SEARCH_SEMANTIC_RANKER string = searchServiceSkuName == 'standard' ? 'enabled' : 'disabled'
 
 output AZURE_STORAGE_ACCOUNT string = storage.outputs.name
 output AZURE_STORAGE_CONTAINER string = storageContainerName

packages/indexer/src/lib/indexer.ts

@@ -37,7 +37,7 @@ export class Indexer {
     this.blobStorage = new BlobStorage(logger, azure);
   }
 
-  async createSearchIndex(indexName: string) {
+  async createSearchIndex(indexName: string, useSemanticRanker = false) {
     this.logger.debug(`Ensuring search index "${indexName}" exists`);
 
     const searchIndexClient = this.azure.searchIndex;
@@ -72,21 +72,25 @@ export class Indexer {
             },
           ],
         },
-        semanticSearch: {
-          defaultConfigurationName: 'semantic-search-config',
-          configurations: [
-            {
-              name: 'semantic-search-config',
-              prioritizedFields: {
-                contentFields: [
+        ...(useSemanticRanker
+          ? {
+              semanticSearch: {
+                defaultConfigurationName: 'semantic-search-config',
+                configurations: [
                   {
-                    name: 'content',
+                    name: 'semantic-search-config',
+                    prioritizedFields: {
+                      contentFields: [
+                        {
+                          name: 'content',
+                        },
+                      ],
+                    },
                   },
                 ],
               },
-            },
-          ],
-        },
+            }
+          : {}),
         fields: [
           {
             name: 'id',

packages/indexer/src/plugins/config.ts

@@ -8,6 +8,7 @@ export interface AppConfig {
   azureStorageContainer: string;
   azureSearchService: string;
   azureSearchIndex: string;
+  azureSearchSemanticRanker: string;
   azureOpenAiService: string;
   azureOpenAiEmbeddingDeployment: string;
   azureOpenAiEmbeddingModel: string;
@@ -28,6 +29,7 @@ export default fp(
       azureStorageAccount: process.env.AZURE_STORAGE_ACCOUNT || '',
       azureStorageContainer: process.env.AZURE_STORAGE_CONTAINER || '',
       azureSearchService: process.env.AZURE_SEARCH_SERVICE || '',
+      azureSearchSemanticRanker: process.env.AZURE_SEARCH_SEMANTIC_RANKER || 'disabled',
       azureSearchIndex: process.env.AZURE_SEARCH_INDEX || '',
       azureOpenAiService: process.env.AZURE_OPENAI_SERVICE || '',
       azureOpenAiEmbeddingDeployment: process.env.AZURE_OPENAI_EMBEDDING_DEPLOYMENT || '',

packages/indexer/src/routes/indexes/index.ts

@@ -33,7 +33,7 @@ const root: FastifyPluginAsyncJsonSchemaToTs = async (fastify, _options): Promis
     handler: async function (request, reply) {
       const { name } = request.body;
       try {
-        await fastify.indexer.createSearchIndex(name);
+        await fastify.indexer.createSearchIndex(name, fastify.config.azureSearchSemanticRanker !== 'enabled');
         reply.code(204);
       } catch (_error: unknown) {
         const error = _error as Error;

packages/search/src/plugins/config.ts

@@ -8,6 +8,7 @@ export interface AppConfig {
   azureStorageContainer: string;
   azureSearchService: string;
   azureSearchIndex: string;
+  azureSearchSemanticRanker: string;
   azureOpenAiService: string;
   azureOpenAiChatGptDeployment: string;
   azureOpenAiChatGptModel: string;
@@ -32,6 +33,7 @@ export default fp(
       azureStorageContainer: process.env.AZURE_STORAGE_CONTAINER || '',
       azureSearchService: process.env.AZURE_SEARCH_SERVICE || '',
       azureSearchIndex: process.env.AZURE_SEARCH_INDEX || '',
+      azureSearchSemanticRanker: process.env.AZURE_SEARCH_SEMANTIC_RANKER || 'disabled',
       azureOpenAiService: process.env.AZURE_OPENAI_SERVICE || '',
       azureOpenAiChatGptDeployment: process.env.AZURE_OPENAI_CHATGPT_DEPLOYMENT || '',
       azureOpenAiChatGptModel: process.env.AZURE_OPENAI_CHATGPT_MODEL || 'gpt-4o-mini',

packages/search/src/routes/root.ts

@@ -5,6 +5,7 @@ import { Readable } from 'node:stream';
 import { type FastifyPluginAsync } from 'fastify';
 import { type JsonSchemaToTsProvider } from '@fastify/type-provider-json-schema-to-ts';
 import { type SchemaTypes } from '../plugins/schemas.js';
+import { type ApproachContext } from '../lib/index.js';
 
 const __dirname = path.dirname(fileURLToPath(import.meta.url));
 
@@ -74,21 +75,26 @@ const root: FastifyPluginAsync = async (_fastify, _options): Promise<void> => {
       }
 
       const { messages, context, stream } = request.body;
+      let approachContext: ApproachContext = (context as any) ?? {};
+      if (this.config.azureSearchSemanticRanker !== 'enabled') {
+        approachContext = { ...approachContext, semantic_ranker: false };
+      }
+
       try {
         if (stream) {
           const buffer = new Readable();
           // Dummy implementation needed
           buffer._read = () => {};
           reply.type('application/x-ndjson').send(buffer);
 
-          const chunks = await chatApproach.runWithStreaming(messages, (context as any) ?? {});
+          const chunks = await chatApproach.runWithStreaming(messages, approachContext);
           for await (const chunk of chunks) {
             buffer.push(JSON.stringify(chunk) + '\n');
           }
           // eslint-disable-next-line unicorn/no-null
           buffer.push(null);
         } else {
-          return await chatApproach.run(messages, (context as any) ?? {});
+          return await chatApproach.run(messages, approachContext);
         }
       } catch (_error: unknown) {
         const error = _error as Error & { error?: any; status?: number };
@@ -121,21 +127,26 @@ const root: FastifyPluginAsync = async (_fastify, _options): Promise<void> => {
       }
 
       const { messages, context, stream } = request.body;
+      let approachContext: ApproachContext = (context as any) ?? {};
+      if (this.config.azureSearchSemanticRanker !== 'enabled') {
+        approachContext = { ...approachContext, semantic_ranker: false };
+      }
+
       try {
         if (stream) {
           const buffer = new Readable();
           // Dummy implementation needed
           buffer._read = () => {};
           reply.type('application/x-ndjson').send(buffer);
 
-          const chunks = await askApproach.runWithStreaming(messages[0].content, (context as any) ?? {});
+          const chunks = await askApproach.runWithStreaming(messages[0].content, approachContext);
           for await (const chunk of chunks) {
             buffer.push(JSON.stringify(chunk) + '\n');
           }
           // eslint-disable-next-line unicorn/no-null
           buffer.push(null);
         } else {
-          return await askApproach.run(messages[0].content, (context as any) ?? {});
+          return await askApproach.run(messages[0].content, approachContext);
         }
       } catch (_error: unknown) {
         const error = _error as Error & { error?: any; status?: number };