matthew/PostConvert
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

Update server.js

Browse Source
This commit is contained in:
Matthew Jackson
2026-01-03 12:45:09 -08:00
committed by GitHub
parent 9ddd76dfd9
commit e07e1c0529
1 changed files with 44 additions and 76 deletions
Download Patch File Download Diff File Expand all files Collapse all files

120
server.js
View File

@@ -6,9 +6,9 @@ import { createReadStream } from "fs";
import path from "path";
import { randomUUID } from "crypto";
import archiver from "archiver";
import libheif from "libheif-js";
const app = express();
app.use(express.raw({ type: "*/*", limit: "30mb" }));
app.get("/", (_req, res) => res.status(200).send("postconvert: ok"));
@@ -30,65 +30,49 @@ function isPdfRequest(req) {
return contentType === "application/pdf" || filename.endsWith(".pdf");
}
function looksLikeHeic(buf) {
// ISO-BMFF "ftyp" at offset 4 is typical for HEIC/HEIF
if (!buf || buf.length < 32) return false;
if (buf.toString("ascii", 4, 8) !== "ftyp") return false;
const brands = buf.toString("ascii", 8, 32);
return (
brands.includes("heic") ||
brands.includes("heif") ||
brands.includes("mif1") ||
brands.includes("msf1")
);
}
// ---------- Core converters ----------
async function toJpegWithSharp(inputBuffer) {
return sharp(inputBuffer, {
failOnError: false,
// Safety: avoid decompression bombs
limitInputPixels: 200e6,
})
return sharp(inputBuffer, { failOnError: false, limitInputPixels: 200e6 })
.rotate()
.jpeg({ quality: 100, chromaSubsampling: "4:4:4" })
.toBuffer();
}
async function toJpegWithFfmpeg(inputBuffer) {
const id = randomUUID();
const inPath = `/tmp/${id}.bin`; // ffmpeg probes; extension not required
const outPath = `/tmp/${id}.jpg`;
async function heicToJpegWithWasm(inputBuffer) {
// Decode HEIC/HEIF to raw RGBA using libheif-js (WASM)
const decoder = new libheif.HeifDecoder();
const images = decoder.decode(inputBuffer);
await fs.writeFile(inPath, inputBuffer);
await execFilePromise("ffmpeg", [
"-y",
"-v",
"error",
"-i",
inPath,
"-frames:v",
"1",
"-q:v",
"1", // high-quality JPEG from ffmpeg
outPath,
]);
const jpg = await fs.readFile(outPath);
// Normalize output with sharp to enforce consistent settings (quality 100, 4:4:4)
return toJpegWithSharp(jpg);
}
async function toJpegWithImagemagick(inputBuffer) {
const id = randomUUID();
const inPath = `/tmp/${id}.bin`;
const outPath = `/tmp/${id}.jpg`;
await fs.writeFile(inPath, inputBuffer);
// ImageMagick 7 uses `magick`; IM6 uses `convert`
// We'll try `magick` first, then fallback to `convert`.
const args = [inPath, "-auto-orient", "-quality", "100", outPath];
try {
await execFilePromise("magick", args);
} catch (e) {
// If magick isn't installed, IM6 usually provides `convert`
await execFilePromise("convert", args);
if (!images || images.length === 0) {
throw new Error("WASM HEIF decode produced no images");
}
const jpg = await fs.readFile(outPath);
return toJpegWithSharp(jpg);
const img = images[0];
// libheif-js exposes width/height; decode to RGBA
const width = img.get_width();
const height = img.get_height();
const rgba = img.display({ data: null, width, height, channels: 4 });
// Encode to JPEG with sharp (consistent settings)
return sharp(Buffer.from(rgba.data), { raw: { width, height, channels: 4 } })
.jpeg({ quality: 100, chromaSubsampling: "4:4:4" })
.toBuffer();
}
async function pdfFirstPageToJpeg(inputBuffer, dpi = 300) {
@@ -113,7 +97,6 @@ async function pdfFirstPageToJpeg(inputBuffer, dpi = 300) {
// ---------- Endpoints ----------
// Single JPEG output (images + PDF first page)
app.post("/convert", async (req, res) => {
try {
if (!requireAuth(req, res)) return;
@@ -128,21 +111,20 @@ app.post("/convert", async (req, res) => {
return res.status(200).send(jpeg);
}
// Non-PDF: sharp -> ffmpeg -> imagemagick
// Try sharp first
try {
const jpeg = await toJpegWithSharp(input);
res.setHeader("Content-Type", "image/jpeg");
return res.status(200).send(jpeg);
} catch (e1) {
try {
const jpeg = await toJpegWithFfmpeg(input);
res.setHeader("Content-Type", "image/jpeg");
return res.status(200).send(jpeg);
} catch (e2) {
const jpeg = await toJpegWithImagemagick(input);
} catch (sharpErr) {
// If it looks like HEIC/HEIF, use WASM decoder (bulletproof)
if (looksLikeHeic(input)) {
const jpeg = await heicToJpegWithWasm(input);
res.setHeader("Content-Type", "image/jpeg");
return res.status(200).send(jpeg);
}
// Otherwise bubble up (or add more fallbacks later if desired)
throw sharpErr;
}
} catch (e) {
console.error(e);
@@ -159,12 +141,9 @@ app.post("/convert/pdf", async (req, res) => {
if (!input || input.length === 0) return res.status(400).send("Empty body");
if (!isPdfRequest(req)) {
return res
.status(415)
.send("This endpoint only accepts PDFs (Content-Type: application/pdf)");
return res.status(415).send("This endpoint only accepts PDFs");
}
// Safety limits
const dpi = clampInt(req.headers["x-pdf-dpi"], 72, 600, 300);
const maxPages = clampInt(req.headers["x-pdf-max-pages"], 1, 200, 50);
@@ -176,13 +155,7 @@ app.post("/convert/pdf", async (req, res) => {
await fs.mkdir(outDir, { recursive: true });
await fs.writeFile(pdfPath, input);
await execFilePromise("pdftoppm", [
"-jpeg",
"-r",
String(dpi),
pdfPath,
outPrefix,
]);
await execFilePromise("pdftoppm", ["-jpeg", "-r", String(dpi), pdfPath, outPrefix]);
const files = (await fs.readdir(outDir))
.filter((f) => /^page-\d+\.jpg$/i.test(f))
@@ -190,17 +163,12 @@ app.post("/convert/pdf", async (req, res) => {
if (files.length === 0) return res.status(500).send("PDF render produced no pages");
if (files.length > maxPages) {
return res
.status(413)
.send(`PDF has ${files.length} pages; exceeds maxPages=${maxPages}`);
return res.status(413).send(`PDF has ${files.length} pages; exceeds maxPages=${maxPages}`);
}
res.status(200);
res.setHeader("Content-Type", "application/zip");
res.setHeader(
"Content-Disposition",
`attachment; filename="pdf-pages-${id}.zip"`
);
res.setHeader("Content-Disposition", `attachment; filename="pdf-pages-${id}.zip"`);
const archive = archiver("zip", { zlib: { level: 6 } });
archive.on("error", (err) => {