Update packages/multipart-parser/src/lib/multipart.ts

Author: Arlen22

packages/multipart-parser/src/lib/multipart.ts

@@ -62,6 +62,14 @@ export interface ParseMultipartOptions {
    * 
    */
   useContentPart?: boolean
+  /**
+   * A callback called for each multipart part created. This is called immediately after the header is parsed, and before any body chunks are processed, including the partial chunk after the header. 
+   * 
+   * If you want to immediately write chunks to the file system, set useContentPart to false, and then set the part.append method of each part this callback is called with. part.append will be called with each chunk, including partial chunks, after the returned promise resolves, and before the iterator yields the completed chunk. 
+   *
+   * This callback and part.append are both awaited.
+   * 
+   */
   onCreatePart?(part: MultipartPart): Promise<void> | void
 }