Merge pull request #14134 from janekotovich/convert_pdf2png_to_async

Convert examples/node/pdf2png/pdf2png.js to await/async
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Jonas Jenwald 2021-10-14 13:11:51 +02:00 committed by GitHub
commit 9f9f07613f
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@ -70,41 +70,40 @@ const loadingTask = pdfjsLib.getDocument({
cMapPacked: CMAP_PACKED,
standardFontDataUrl: STANDARD_FONT_DATA_URL,
});
loadingTask.promise
.then(function (pdfDocument) {
(async function () {
try {
const pdfDocument = await loadingTask.promise;
console.log("# PDF document loaded.");
// Get the first page.
pdfDocument.getPage(1).then(function (page) {
// Render the page on a Node canvas with 100% scale.
const viewport = page.getViewport({ scale: 1.0 });
const canvasFactory = new NodeCanvasFactory();
const canvasAndContext = canvasFactory.create(
viewport.width,
viewport.height
);
const renderContext = {
canvasContext: canvasAndContext.context,
viewport,
canvasFactory,
};
const page = await pdfDocument.getPage(1);
// Render the page on a Node canvas with 100% scale.
const viewport = page.getViewport({ scale: 1.0 });
const canvasFactory = new NodeCanvasFactory();
const canvasAndContext = canvasFactory.create(
viewport.width,
viewport.height
);
const renderContext = {
canvasContext: canvasAndContext.context,
viewport,
canvasFactory,
};
const renderTask = page.render(renderContext);
renderTask.promise.then(function () {
// Convert the canvas to an image buffer.
const image = canvasAndContext.canvas.toBuffer();
fs.writeFile("output.png", image, function (error) {
if (error) {
console.error("Error: " + error);
} else {
console.log(
"Finished converting first page of PDF file to a PNG image."
);
}
});
});
const renderTask = page.render(renderContext);
await renderTask.promise;
// Convert the canvas to an image buffer.
const image = canvasAndContext.canvas.toBuffer();
fs.writeFile("output.png", image, function (error) {
if (error) {
console.error("Error: " + error);
} else {
console.log(
"Finished converting first page of PDF file to a PNG image."
);
}
});
})
.catch(function (reason) {
} catch (reason) {
console.log(reason);
});
}
})();