From 5a28512fe5530ae2f75ef77cdd7fd9b4fe3475c7 Mon Sep 17 00:00:00 2001
From: Helen Kwok <107752876+helenkwok@users.noreply.github.com>
Date: Sun, 11 Oct 2026 15:05:03 +1030
Subject: [PATCH] fix(client): upload a bare Blob under the item name

The platform takes fileExtension from the multipart filename. A Blob passed to
createFile or updateFile was appended without one, so it went up as "blob"
and the item was stored with fileExtension "", which Automation extension
conditions never match.
---
 .changeset/blob-upload-filename.md |  5 +++++
 src/core/client.test.ts            | 29 +++++++++++++++++++++++++++++
 src/core/client.ts                 | 19 +++++++++++++++++--
 src/core/examples/files.ts         |  1 +
 4 files changed, 52 insertions(+), 2 deletions(-)
 create mode 100644 .changeset/blob-upload-filename.md

diff --git a/.changeset/blob-upload-filename.md b/.changeset/blob-upload-filename.md
new file mode 100644
index 0000000..fce728e
--- /dev/null
+++ b/.changeset/blob-upload-filename.md
@@ -0,0 +1,5 @@
+---
+'@thatopen/services': patch
+---
+
+`createFile` and `updateFile` (when a name is given) upload a bare `Blob` under the item's name, so the item gets its `fileExtension` instead of an empty one.
diff --git a/src/core/client.test.ts b/src/core/client.test.ts
index 6f4ab92..62aed05 100644
--- a/src/core/client.test.ts
+++ b/src/core/client.test.ts
@@ -232,6 +232,35 @@ describe('EngineServicesClient — HTTP contract', () => {
     });
   });
 
+  describe('upload filename', () => {
+    // The platform takes fileExtension from the multipart filename; a bare
+    // Blob would be sent as "blob" and stored with fileExtension "".
+    it('createFile sends a bare Blob under the item name', async () => {
+      fetchMock.mockResolvedValue(okResponse({}));
+      const client = new EngineServicesClient(TOKEN, API);
+      await client.createFile({ file: new Blob(['{}']), name: 'result.json', versionTag: 'v1' });
+      const file = (getCall(fetchMock).init.body as FormData).get('file') as File;
+      expect(file.name).toBe('result.json');
+      expect(await file.text()).toBe('{}');
+    });
+
+    it('createFile keeps a File\'s own name', async () => {
+      fetchMock.mockResolvedValue(okResponse({}));
+      const client = new EngineServicesClient(TOKEN, API);
+      await client.createFile({ file: new File(['x'], 'model.ifc'), name: 'Model', versionTag: 'v1' });
+      const file = (getCall(fetchMock).init.body as FormData).get('file') as File;
+      expect(file.name).toBe('model.ifc');
+    });
+
+    it('updateFile names a bare Blob when a name is given', async () => {
+      fetchMock.mockResolvedValue(okResponse({}));
+      const client = new EngineServicesClient(TOKEN, API);
+      await client.updateFile('item-1', { file: new Blob(['{}']), name: 'result.json', versionTag: 'v2' });
+      const file = (getCall(fetchMock).init.body as FormData).get('file') as File;
+      expect(file.name).toBe('result.json');
+    });
+  });
+
   describe('error handling', () => {
     it('throws when the server responds with a non-2xx status', async () => {
       fetchMock.mockResolvedValue(errorResponse(403, 'Forbidden'));
diff --git a/src/core/client.ts b/src/core/client.ts
index f3c81cd..19ed2e9 100644
--- a/src/core/client.ts
+++ b/src/core/client.ts
@@ -229,6 +229,14 @@ export type EngineServicesClientProps = {
  * const files = await client.listFiles();
  * ```
  */
+/**
+ * The platform takes a file's extension from the upload's filename, and a bare
+ * Blob is sent as "blob". Give it the item's name so `fileExtension` is set.
+ */
+function namedFile(file: File | Blob, name: string): File | Blob {
+  return file instanceof File ? file : new File([file], name, { type: file.type });
+}
+
 export class EngineServicesClient {
   private apiUrl: string;
   private accessToken: string;
@@ -557,7 +565,10 @@ export class EngineServicesClient {
    * @returns The created item and its first version.
    */
   async createFile(fileData: CreateItemProps) {
-    return await this.#createItem(fileData, ITEM_TYPE_FILE);
+    return await this.#createItem(
+      { ...fileData, file: namedFile(fileData.file, fileData.name) },
+      ITEM_TYPE_FILE,
+    );
   }
 
   /**
@@ -571,7 +582,11 @@ export class EngineServicesClient {
     fileId: string,
     fileData: UpdateItemProps,
   ): Promise<UpdateItemResponse> {
-    return await this.#updateItem(fileId, fileData);
+    const { file, name } = fileData;
+    return await this.#updateItem(
+      fileId,
+      file && name ? { ...fileData, file: namedFile(file, name) } : fileData,
+    );
   }
 
   /**
diff --git a/src/core/examples/files.ts b/src/core/examples/files.ts
index d555fca..625c4ad 100644
--- a/src/core/examples/files.ts
+++ b/src/core/examples/files.ts
@@ -39,6 +39,7 @@ async function main() {
   // projectId is required — the backend rejects uploads without one.
   const fileName = `__example-test__-${Date.now()}.json`;
   const blob = new Blob([JSON.stringify({ test: true })], { type: 'application/json' });
+  // A bare Blob is uploaded under `name`, so the item takes its fileExtension from it.
   const created = await client.createFile({ file: blob, name: fileName, versionTag: 'v1', projectId: PROJECT_ID });
   console.log(`\nCreated file: [${created.item._id}] ${created.item.name}`);