feat(Databricks Node): Guard the Vector Store insert against the wrong index (#39699)

packages/@n8n/nodes-langchain/nodes/vector_store/VectorStoreDatabricks/DatabricksVectorStore.test.ts

@@ -460,16 +460,38 @@ describe('DatabricksVectorStore', () => {
 			).rejects.toThrow('Failed primary keys: row-7');
 		});
 
-		it('rejects the primary key as the content column without a request', async () => {
-			const store = await createStore(directDescribe, { contentColumn: 'id' });
+		it.each([
+			['txet', 'Index cat.sch.idx has no column txet. Select a Content Column from: text, source'],
+			['id', 'Column id is the primary key of cat.sch.idx. Select another Content Column'],
+			[
+				'embedding',
+				'Column embedding holds the embedding vector of cat.sch.idx. Select another Content Column',
+			],
+		])('rejects %s as the content column before embedding anything', async (column, message) => {
+			const store = await createStore(directDescribe, { contentColumn: column });
 
 			await expect(store.addDocuments([{ pageContent: 'hello', metadata: {} }])).rejects.toThrow(
-				'primary key',
+				message,
 			);
-			expect(fetchMock).not.toHaveBeenCalledWith(
-				expect.stringContaining('upsert-data'),
-				expect.anything(),
+			expect(embeddings.embedDocuments).not.toHaveBeenCalled();
+			expect(fetchMock).not.toHaveBeenCalled();
+		});
+
+		it('rejects an index that declares an empty schema, rather than letting Databricks reject it', async () => {
+			const emptySchema = {
+				...directDescribe,
+				direct_access_index_spec: {
+					...directDescribe.direct_access_index_spec,
+					schema_json: '{}',
+				},
+			};
+			const store = await createStore(emptySchema, { contentColumn: 'text' });
+
+			await expect(store.addDocuments([{ pageContent: 'hello', metadata: {} }])).rejects.toThrow(
+				'Index cat.sch.idx has no column text, and declares no other column to select',
 			);
+			expect(embeddings.embedDocuments).not.toHaveBeenCalled();
+			expect(fetchMock).not.toHaveBeenCalled();
 		});
 
 		it('rejects a managed Delta Sync index without a request', async () => {

packages/@n8n/nodes-langchain/nodes/vector_store/VectorStoreDatabricks/DatabricksVectorStore.ts

@@ -299,7 +299,7 @@ export class DatabricksVectorStore extends VectorStore {
 		options?: { ids?: string[] },
 	): Promise<string[]> {
 		if (documents.length === 0) return [];
-		this.assertDirectAccess();
+		this.assertWritableContentColumn();
 		const vectors = await this.embeddings.embedDocuments(documents.map((doc) => doc.pageContent));
 		return await this.addVectors(vectors, documents, options);
 	}
@@ -309,14 +309,8 @@ export class DatabricksVectorStore extends VectorStore {
 		documents: DocumentInterface[],
 		options?: { ids?: string[] },
 	): Promise<string[]> {
-		const vectorColumn = this.assertDirectAccess();
+		const vectorColumn = this.assertWritableContentColumn();
 		const { primaryKey, name } = this.index;
-		// The row below would write the document text over its own primary key
-		if (this.contentColumn === primaryKey) {
-			throw new UserError(
-				`Column ${primaryKey} is the primary key of ${name}. Select another content column`,
-			);
-		}
 		const schemaColumns = new Set(this.index.schemaColumns ?? []);
 		const ids = documents.map((doc, i) => options?.ids?.[i] ?? doc.id ?? randomUUID());
 
@@ -347,6 +341,33 @@ export class DatabricksVectorStore extends VectorStore {
 		return ids;
 	}
 
+	/** Both writes below would land on a column the row already fills from somewhere else. */
+	private assertWritableContentColumn(): string {
+		const vectorColumn = this.assertDirectAccess();
+		const { primaryKey, name, schemaColumns } = this.index;
+		if (this.contentColumn === primaryKey) {
+			throw new UserError(
+				`Column ${primaryKey} is the primary key of ${name}. Select another Content Column`,
+			);
+		}
+		if (this.contentColumn === vectorColumn) {
+			throw new UserError(
+				`Column ${vectorColumn} holds the embedding vector of ${name}. Select another Content Column`,
+			);
+		}
+		// An index that declares an empty schema is known, not unknown: letting it
+		// through trades this message for a raw Databricks schema error.
+		if (schemaColumns !== undefined && !schemaColumns.includes(this.contentColumn)) {
+			const selectable = schemaColumns.filter((column) => !this.reserved.has(column));
+			throw new UserError(
+				selectable.length > 0
+					? `Index ${name} has no column ${this.contentColumn}. Select a Content Column from: ${selectable.join(', ')}`
+					: `Index ${name} has no column ${this.contentColumn}, and declares no other column to select`,
+			);
+		}
+		return vectorColumn;
+	}
+
 	// Databricks enforces `index_type` here; a Delta Sync index rejects upsert-data even when it holds its own vectors
 	private assertDirectAccess(): string {
 		const { indexType, embedding, name } = this.index;

packages/@n8n/nodes-langchain/nodes/vector_store/VectorStoreDatabricks/VectorStoreDatabricks.node.test.ts

@@ -1,6 +1,7 @@
 /* eslint-disable n8n-nodes-base/node-param-display-name-miscased */
 /* eslint-disable n8n-nodes-base/node-param-display-name-miscased-id */
 import type { Embeddings } from '@langchain/core/embeddings';
+import type { Tool } from '@langchain/core/tools';
 import { proxyFetch } from '@n8n/ai-utilities';
 import { DATABRICKS_PARTNER_USER_AGENT } from 'n8n-nodes-base/dist/nodes/Databricks/constants';
 import { createMockExecuteFunction } from 'n8n-nodes-base/test/nodes/Helpers';
@@ -327,6 +328,60 @@ describe('VectorStoreDatabricks', () => {
 		});
 	});
 
+	describe('supplyData in retrieve-as-tool mode', () => {
+		// A managed-embedding index rejects query_vector, so the agent's query has to reach the
+		// store as text. The factory picks that path from this node's `searchByText`.
+		it('searches the agent query as text and never embeds it', async () => {
+			const store = { similaritySearchWithScore: vi.fn().mockResolvedValue([]) };
+			mockedFromExistingIndex.mockResolvedValue(store as unknown as DatabricksVectorStore);
+			const ctx = setupContext<ISupplyDataFunctions>({
+				...baseParams,
+				mode: 'retrieve-as-tool',
+				toolDescription: 'Company policies. Use for any policy question.',
+				topK: 3,
+			});
+			ctx.addInputData = vi.fn().mockReturnValue({ index: 0 });
+			ctx.addOutputData = vi.fn();
+
+			const { response } = await node.supplyData.call(ctx, 0);
+			await (response as Tool).invoke({ input: 'what is the leave policy' });
+
+			expect(store.similaritySearchWithScore).toHaveBeenCalledWith(
+				'what is the leave policy',
+				3,
+				undefined,
+			);
+			expect(embeddings.embedQuery).not.toHaveBeenCalled();
+		});
+
+		// An agent-driven search must use the node's own configuration. The community package
+		// drops the mode and the filter on this path, which is the regression this pins.
+		it('carries the configured search mode, metadata filter and limit into the tool search', async () => {
+			const store = { similaritySearchWithScore: vi.fn().mockResolvedValue([]) };
+			mockedFromExistingIndex.mockResolvedValue(store as unknown as DatabricksVectorStore);
+			const ctx = setupContext<ISupplyDataFunctions>({
+				...baseParams,
+				mode: 'retrieve-as-tool',
+				toolDescription: 'Company policies. Use for any policy question.',
+				topK: 3,
+				options: { searchMode: 'HYBRID', searchFilterJson: { source: 'hr' } },
+			});
+			ctx.addInputData = vi.fn().mockReturnValue({ index: 0 });
+			ctx.addOutputData = vi.fn();
+
+			const { response } = await node.supplyData.call(ctx, 0);
+			await (response as Tool).invoke({ input: 'what is the leave policy' });
+
+			expect(mockedFromExistingIndex).toHaveBeenCalledWith(
+				embeddings,
+				expect.objectContaining({ queryType: 'HYBRID' }),
+			);
+			expect(store.similaritySearchWithScore).toHaveBeenCalledWith('what is the leave policy', 3, {
+				source: 'hr',
+			});
+		});
+	});
+
 	describe('execute in insert mode', () => {
 		it('adds the loaded documents through the store', async () => {
 			const documents = [
@@ -369,7 +424,7 @@ describe('VectorStoreDatabricks', () => {
 		let httpRequestWithAuthentication: ReturnType<typeof vi.fn>;
 		let ctx: ILoadOptionsFunctions;
 
-		const setupSearchContext = (host: string) => {
+		const setupSearchContext = (host: string, mode = 'load') => {
 			httpRequestWithAuthentication = vi.fn(
 				async (_type: string, options: { url: string; qs: Record<string, string> }) =>
 					options.url.endsWith('/endpoints')
@@ -378,6 +433,7 @@ describe('VectorStoreDatabricks', () => {
 			);
 			ctx = {
 				getCredentials: vi.fn().mockResolvedValue({ ...mockCredential, host }),
+				getCurrentNodeParameter: vi.fn((path: string) => (path === 'mode' ? mode : undefined)),
 				getNode: vi.fn().mockReturnValue(nodeDef),
 				helpers: { httpRequestWithAuthentication },
 			} as unknown as ILoadOptionsFunctions;
@@ -401,6 +457,21 @@ describe('VectorStoreDatabricks', () => {
 			}
 		});
 
+		// Only insert writes, so only insert may narrow the list; the read modes query both types.
+		it.each([
+			['insert', ['cat.sch.zeta']],
+			['load', ['cat.sch.alpha', 'cat.sch.beta', 'cat.sch.zeta']],
+			['retrieve', ['cat.sch.alpha', 'cat.sch.beta', 'cat.sch.zeta']],
+			['retrieve-as-tool', ['cat.sch.alpha', 'cat.sch.beta', 'cat.sch.zeta']],
+		])('offers the writable indexes in %s mode', async (mode, expected) => {
+			setupSearchContext('https://ws.example.com/', mode);
+
+			const result = await methods.listSearch.searchIndexes.call(ctx);
+
+			expect(result.results.map((entry) => entry.value)).toEqual(expected);
+			expect(ctx.getCurrentNodeParameter).toHaveBeenCalledWith('mode');
+		});
+
 		it('does not let the bearer follow a cross-origin redirect', async () => {
 			setupSearchContext('https://ws.example.com');
 

packages/@n8n/nodes-langchain/nodes/vector_store/VectorStoreDatabricks/VectorStoreDatabricks.node.ts

@@ -231,6 +231,7 @@ async function searchIndexes(
 	this: ILoadOptionsFunctions,
 	filter?: string,
 ): Promise<INodeListSearchResult> {
+	const insertOnly = this.getCurrentNodeParameter('mode') === 'insert';
 	const credentials = await this.getCredentials<DatabricksOAuth2Credential>(
 		DATABRICKS_CREDENTIAL_TYPE,
 	);
@@ -252,12 +253,13 @@ async function searchIndexes(
 					{ endpoint_name: endpoint.name },
 					(page: ListPage) => page.vector_indexes,
 				);
-				// The type tells the user which indexes accept inserts
-				return indexes.map((index) => ({
-					name: index.name,
-					value: index.name,
-					description: `${index.index_type} - ${endpoint.name}`,
-				}));
+				return indexes
+					.filter((index) => !insertOnly || index.index_type === 'DIRECT_ACCESS')
+					.map((index) => ({
+						name: index.name,
+						value: index.name,
+						description: `${index.index_type} - ${endpoint.name}`,
+					}));
 			}),
 		)
 	)