import * as fs from "node:fs"; import type Koa from "koa"; import sharp from "sharp"; import type { IImage } from "@/services/drive/image-processor.js"; import { convertToWebp } from "@/services/drive/image-processor.js"; import { createTemp } from "@/misc/create-temp.js"; import { downloadUrl } from "@/misc/download-url.js"; import { detectType } from "@/misc/get-file-info.js"; import { StatusError } from "@/misc/fetch.js"; import { FILE_TYPE_BROWSERSAFE } from "@/const.js"; import { serverLogger } from "../index.js"; import { isMimeImage } from "@/misc/is-mime-image.js"; export async function proxyMedia(ctx: Koa.Context) { const url = "url" in ctx.query ? ctx.query.url : `https://${ctx.params.url}`; if (typeof url !== "string") { ctx.status = 400; return; } // Create temp file const [path, cleanup] = await createTemp(); try { await downloadUrl(url, path); const { mime, ext } = await detectType(path); const isConvertibleImage = isMimeImage(mime, "sharp-convertible-image"); let image: IImage; if ("static" in ctx.query && isConvertibleImage) { image = await convertToWebp(path, 498, 280); } else if ("preview" in ctx.query && isConvertibleImage) { image = await convertToWebp(path, 200, 200); } else if ("badge" in ctx.query) { if (!isConvertibleImage) { // 画像でないなら404でお茶を濁す throw new StatusError("Unexpected mime", 404); } const mask = sharp(path) .resize(96, 96, { fit: "inside", withoutEnlargement: false, }) .greyscale() .normalise() .linear(1.75, -(128 * 1.75) + 128) // 1.75x contrast .flatten({ background: "#000" }) .toColorspace("b-w"); const stats = await mask.clone().stats(); if (stats.entropy < 0.1) { // エントロピーがあまりない場合は404にする throw new StatusError("Skip to provide badge", 404); } const data = sharp({ create: { width: 96, height: 96, channels: 4, background: { r: 0, g: 0, b: 0, alpha: 0 }, }, }) .pipelineColorspace("b-w") .boolean(await mask.png().toBuffer(), "eor"); image = { data: await data.png().toBuffer(), ext: "png", type: "image/png", }; } else if (mime === "image/svg+xml") { image = await convertToWebp(path, 2048, 2048, 1); } else if ( !(mime.startsWith("image/") && FILE_TYPE_BROWSERSAFE.includes(mime)) ) { throw new StatusError("Rejected type", 403, "Rejected type"); } else { image = { data: fs.readFileSync(path), ext, type: mime, }; } ctx.set("Content-Type", image.type); ctx.set("Cache-Control", "max-age=31536000, immutable"); ctx.body = image.data; } catch (e) { serverLogger.error(`${e}`); if (e instanceof StatusError && (e.statusCode === 302 || e.isClientError)) { ctx.status = e.statusCode; } else { ctx.status = 500; } } finally { cleanup(); } }