Helpers

Import from @dimah-s3/server or @dimah-s3/core.

ACL and metadata

Resolve object ACL

GetObjectAcl to "public-read" | "private" | undefined.

Set resolveObjectAcl: true in DimahS3Config to run this automatically on upload confirm and multipart complete.

import { resolveObjectAcl } from "@dimah-s3/server";

const acl = await resolveObjectAcl(s3, bucket, key);
// "public-read" | "private" | undefined

await resolveObjectAcl(s3, bucket, key, 3_000); // optional timeout (default 1500 ms)

Build content disposition

RFC 6266 attachment header with ASCII filename and Unicode-safe filename*.

Applied automatically when the client sends fileName in a presign request.

import { buildContentDisposition } from "@dimah-s3/core";

buildContentDisposition("Q4 Report.pdf");
// attachment; filename="Q4 Report.pdf"; filename*=UTF-8''Q4%20Report.pdf

buildContentDisposition("گزارش.pdf");
// attachment; filename="_____.pdf"; filename*=UTF-8''%DA%AF%D8%B2%D8%A7%D8%B1%D8%B4.pdf

Parse file name

Reads filename* first, then falls back to filename.

import { parseFileName } from "@dimah-s3/core";

parseFileName('attachment; filename="photo.jpg"');
// "photo.jpg"

parseFileName("attachment; filename*=UTF-8''%E6%8A%A5%E5%91%8A.pdf");
// "报告.pdf"

parseFileName(head.ContentDisposition);
// "photo.jpg" | undefined

Object key and extension

Build object key

Joins path segments, trims slashes, skips empty segments.

import { buildObjectKey } from "@dimah-s3/core";

buildObjectKey("uploads", userId, "avatar.png");
// "uploads/user-123/avatar.png"

buildObjectKey("/uploads/", "/", userId, "/avatar.png/");
// "uploads/user-123/avatar.png"

Get file extension

Returns lowercase extension without the dot. Empty string when not found.

import { getFileExtension } from "@dimah-s3/core";

getFileExtension("archive.TAR.GZ"); // "gz"
getFileExtension("photo.jpg"); // "jpg"
getFileExtension("README"); // ""