diff options
Diffstat (limited to 'src/server/ApiManagers/PDFManager.ts')
| -rw-r--r-- | src/server/ApiManagers/PDFManager.ts | 134 |
1 files changed, 64 insertions, 70 deletions
diff --git a/src/server/ApiManagers/PDFManager.ts b/src/server/ApiManagers/PDFManager.ts index 4bd750aaf..151b48dd9 100644 --- a/src/server/ApiManagers/PDFManager.ts +++ b/src/server/ApiManagers/PDFManager.ts @@ -4,10 +4,11 @@ import RouteSubscriber from "../RouteSubscriber"; import { exists, createReadStream, createWriteStream } from "fs"; import * as Pdfjs from 'pdfjs-dist'; import { createCanvas } from "canvas"; -const probe = require("probe-image-size"); +const imageSize = require("probe-image-size"); import * as express from "express"; import * as path from "path"; import { Directory, serverPathToFile, clientPathToFile } from "./UploadManager"; +import { ConsoleColors } from "../ActionUtilities"; export default class PDFManager extends ApiManager { @@ -16,84 +17,77 @@ export default class PDFManager extends ApiManager { register({ method: Method.GET, subscription: new RouteSubscriber("thumbnail").add("filename"), - onValidation: ({ req, res }) => { - let filename = req.params.filename; - let noExt = filename.substring(0, filename.length - ".png".length); - let pagenumber = parseInt(noExt.split('-')[1]); - return new Promise<void>(resolve => { - const path = serverPathToFile(Directory.pdf_thumbnails, filename); - exists(path, (exists: boolean) => { - console.log(`${path} ${exists ? "exists" : "does not exist"}`); - if (exists) { - let input = createReadStream(path); - probe(input, (err: any, { width, height }: any) => { - if (err) { - console.log(err); - console.log(`error on ${filename}`); - return; - } - res.send({ - path: clientPathToFile(Directory.pdf_thumbnails, filename), - width, - height - }); - }); - } - else { - const name = filename.substring(0, filename.length - noExt.split('-')[1].length - ".PNG".length - 1) + ".pdf"; - LoadPage(serverPathToFile(Directory.pdfs, name), pagenumber, res); - } - resolve(); - }); - }); - } + onValidation: ({ req, res }) => getOrCreateThumbnail(req.params.filename, res) }); - function LoadPage(file: string, pageNumber: number, res: express.Response) { - console.log(file); - Pdfjs.getDocument(file).promise - .then((pdf: Pdfjs.PDFDocumentProxy) => { - let factory = new NodeCanvasFactory(); - console.log(pageNumber); - pdf.getPage(pageNumber).then((page: Pdfjs.PDFPageProxy) => { - console.log("reading " + page); - let viewport = page.getViewport(1 as any); - let canvasAndContext = factory.create(viewport.width, viewport.height); - let renderContext = { - canvasContext: canvasAndContext.context, - canvasFactory: factory, - viewport - }; - console.log("read " + pageNumber); + } - page.render(renderContext).promise - .then(() => { - console.log("saving " + pageNumber); - let stream = canvasAndContext.canvas.createPNGStream(); - let filenames = path.basename(file).split("."); - const pngFile = serverPathToFile(Directory.pdf_thumbnails, `${filenames[0]}-${pageNumber}.png`); - let out = createWriteStream(pngFile); - stream.pipe(out); - out.on("finish", () => { - console.log(`Success! Saved to ${pngFile}`); - res.send({ - path: pngFile, - width: viewport.width, - height: viewport.height - }); - }); - }, (reason: string) => { - console.error(reason + ` ${pageNumber}`); - }); +} + +function getOrCreateThumbnail(thumbnailName: string, res: express.Response) { + const noExtension = thumbnailName.substring(0, thumbnailName.length - ".png".length); + const pageString = noExtension.split('-')[1]; + const pageNumber = parseInt(pageString); + return new Promise<void>(resolve => { + const path = serverPathToFile(Directory.pdf_thumbnails, thumbnailName); + exists(path, (exists: boolean) => { + if (exists) { + let existingThumbnail = createReadStream(path); + imageSize(existingThumbnail, (err: any, { width, height }: any) => { + if (err) { + console.log(ConsoleColors.Red, `In PDF thumbnail response, unable to determine dimensions of ${thumbnailName}:`); + console.log(err); + return; + } + res.send({ + path: clientPathToFile(Directory.pdf_thumbnails, thumbnailName), + width, + height }); }); - } - - } + } else { + const offset = thumbnailName.length - pageString.length - 5; + const name = thumbnailName.substring(0, offset) + ".pdf"; + const path = serverPathToFile(Directory.pdfs, name); + CreateThumbnail(path, pageNumber, res); + } + resolve(); + }); + }); +} +async function CreateThumbnail(file: string, pageNumber: number, res: express.Response) { + const documentProxy = await Pdfjs.getDocument(file).promise; + const factory = new NodeCanvasFactory(); + const page = await documentProxy.getPage(pageNumber); + const viewport = page.getViewport(1 as any); + const { canvas, context } = factory.create(viewport.width, viewport.height); + const renderContext = { + canvasContext: context, + canvasFactory: factory, + viewport + }; + await page.render(renderContext).promise; + const pngStream = canvas.createPNGStream(); + const filenames = path.basename(file).split("."); + const pngFile = serverPathToFile(Directory.pdf_thumbnails, `${filenames[0]}-${pageNumber}.png`); + const out = createWriteStream(pngFile); + pngStream.pipe(out); + out.on("finish", () => { + res.send({ + path: pngFile, + width: viewport.width, + height: viewport.height + }); + }); + out.on("error", error => { + console.log(ConsoleColors.Red, `In PDF thumbnail creation, encountered the following error when piping ${pngFile}:`); + console.log(error); + }); } class NodeCanvasFactory { + create = (width: number, height: number) => { var canvas = createCanvas(width, height); var context = canvas.getContext('2d'); |