Files
2026-05-07 21:15:27 -06:00

58 lines
1.7 KiB
TypeScript

import { writeFile } from "node:fs/promises";
import path from "node:path";
import { randomUUID } from "node:crypto";
import type { CreateFlowUploadPurpose } from "./uploadConstants";
import {
extensionForMime,
isAllowedMime,
maxBytesForPurpose,
} from "./uploadConstants";
import { ensureUploadRootExists, getUploadRootFromEnv } from "./uploadRoot";
export type SaveCreateFlowUploadResult = {
/** Filename stem (UUID) without extension — used in GET URL. */
id: string;
/** Full relative URL path for clients, e.g. `/api/uploads/abc`. */
urlPath: string;
mimeType: string;
byteLength: number;
};
/**
* Writes bytes under `UPLOAD_ROOT/{id}{ext}` and returns a stable app URL path.
*/
export async function saveCreateFlowUpload(params: {
purpose: CreateFlowUploadPurpose;
buffer: Buffer;
/** Declared MIME from the client `File.type` (validated server-side). */
mimeType: string;
}): Promise<SaveCreateFlowUploadResult | { error: "misconfigured" | "validation" }> {
const root = getUploadRootFromEnv();
if (!root) {
return { error: "misconfigured" };
}
const { purpose, buffer, mimeType } = params;
if (buffer.length > maxBytesForPurpose(purpose)) {
return { error: "validation" };
}
if (!isAllowedMime(purpose, mimeType)) {
return { error: "validation" };
}
const id = randomUUID();
const ext = extensionForMime(mimeType);
const fileName = `${id}${ext}`;
const absolutePath = path.join(root, fileName);
await ensureUploadRootExists(root);
await writeFile(absolutePath, buffer, { mode: 0o644 });
return {
id,
urlPath: `/api/uploads/${id}`,
mimeType: mimeType.toLowerCase().split(";")[0]?.trim() ?? "application/octet-stream",
byteLength: buffer.length,
};
}