Files
gerbeur/api/routes/attachments.ts
khannurien 90fc281e90 v4: every image the API serves comes scaled to the size it is shown at — a first visit to the feed loaded 4.8 MB of images out of 5.1 MB in all: an avatar shown at 32 pixels was the upload itself, a 1.4 MB GIF among them, and so were a cover, a custom thumbnail, an attachment and a proxied image, only an image dump having a preview, 960 pixels wide. Every route that answers an image now takes ?w= and sends a WebP copy at most that wide, of the widths shared/image.ts lists, 128, 320, 640 and 960, a width between two taking the one above, and never wider than the image; without it the upload goes out as before, a dump's thumbnail alone being scaled to the widest by default, the custom ones included. serveImage (lib/upload.ts) is where they all end, and the image proxy scales what it fetched the same way, keeping each width in its cache. lib/ffmpeg.ts makes the copies as it made the previews, which they replace: on first request, under uploads/scaled/ at the upload's own path, each given its upload's date and made again when the two differ, so a new avatar or cover needs nobody to delete the old ones. WebP keeps a PNG's transparency and a GIF's animation. A JPEG is turned by its EXIF orientation here, ffmpeg's own rotation of images depending on its version. An animated WebP, which ffmpeg can't read, and an image it fails on go out as they are, a failure being remembered until the upload changes. ?f=compat asks for the copy as a JPEG, or a PNG for what may be transparent: the digest's emails take their thumbnails that way, at 640 pixels, not every mail client reading WebP. On the client, imageProps (utils/shared/urls.ts) gives an image its srcset of those copies and the width it is laid out at, which config/imageSizes.ts states for each place from App.css: Avatar, Thumbnail, which scales an API image and leaves another site's as that site sends it, and the playlists' covers use it. The images of notes and comments still load as uploaded. The copies go with the dump, the custom thumbnail or the attachment they were made from, and generatedMediaSweepJob, a minute after the start then daily, takes those whose upload is gone, the previews under their former name and the temporary files a generation left unfinished.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
2026-10-10 19:01:36 +00:00

99 lines
3.0 KiB
TypeScript

/**
* Stores and serves the images pasted or dropped into the text editor, which
* puts each one in the body as a link to its `GET` URL.
*
* - `POST /api/attachments` — signed in. Stores an image (multipart `file`, at
* most 5 MB) and answers its id.
* - `GET /api/attachments/:attachmentId?w=&token=` — public, but an image in
* a private dump or playlist, or in a comment on a private dump, needs its
* owner's media `token`. Serves the image, scaled down to `w`
* (`shared/image.ts`) when it names one.
*
* @module
*/
import { Router } from "@oak/oak";
import { authMiddleware } from "../middleware/auth.ts";
import {
createAttachment,
getAttachmentAccess,
} from "../services/attachment-service.ts";
import { authenticateMedia } from "../lib/auth.ts";
import { type APIResponse } from "../../shared/api.ts";
import { APIException } from "../lib/api-exception.ts";
import type { AttachmentResponse } from "../../shared/attachment.ts";
import { serveUploadedFile, validateImageUpload } from "../lib/upload.ts";
import { ATTACHMENTS_DIR } from "../config.ts";
/**
* Mounted by `api/main.ts` behind the error, Open Graph and CORS middleware.
* An `APIException` thrown by a handler becomes the JSON error response there.
*/
const router: Router = new Router();
router.post("/api/attachments", authMiddleware, async (ctx) => {
const contentType = ctx.request.headers.get("content-type") ?? "";
if (!contentType.includes("multipart/form-data")) {
throw new APIException(400, "Expected multipart/form-data");
}
const body = await ctx.request.body.formData();
const file = body.get("file");
if (!(file instanceof File)) {
throw new APIException(400, "Missing file");
}
const data = new Uint8Array(await file.arrayBuffer());
const mime = validateImageUpload(data);
const attachmentId = crypto.randomUUID();
await Deno.mkdir(ATTACHMENTS_DIR, { recursive: true });
await Deno.writeFile(`${ATTACHMENTS_DIR}/${attachmentId}`, data);
try {
createAttachment(attachmentId, mime);
} catch (err) {
await Deno.remove(`${ATTACHMENTS_DIR}/${attachmentId}`).catch(() => {});
throw err;
}
const responseBody: APIResponse<AttachmentResponse> = {
success: true,
data: { id: attachmentId },
};
ctx.response.status = 201;
ctx.response.body = responseBody;
});
router.get("/api/attachments/:attachmentId", async (ctx) => {
const { attachmentId } = ctx.params;
let access;
try {
access = getAttachmentAccess(attachmentId);
} catch {
ctx.response.status = 404;
return;
}
if (access.ownerId) {
// An <img> can't send an Authorization header, so the viewer's media
// token comes in the query string.
const token = ctx.request.url.searchParams.get("token");
const viewerId = token ? await authenticateMedia(token) : null;
if (viewerId !== access.ownerId) {
ctx.response.status = 404;
return;
}
}
await serveUploadedFile(
ctx,
`${ATTACHMENTS_DIR}/${attachmentId}`,
access.mime,
3600,
!!access.ownerId,
);
});
export default router;