Added error handling so the server doesn't crash

Author: Andrey

files/document.docx.pdf.txt

@@ -0,0 +1,31 @@
+Sample DOCX Document
+This document is just a sample of a docx document.
+It might include a table:
+Heading 1
+Entry 1
+Entry 2
+And some lorem ipsum:
+Lorem ipsum dolor sit amet, consectetur adipiscing elit. Aenean dui neque, hendrerit ac
+vulputate ac, dictum at urna. Vivamus pulvinar tempor lacus, vel aliquet lectus sollicitudin id.
+Phasellus eu volutpat erat. Nullam orci augue, malesuada vel tristique id, porta a lectus. Nunc
+sollicitudin, mi sit amet lobortis ultrices, mi libero egestas eros, consectetur euismod velit ante
+vel nibh. Phasellus in urna vehicula, vestibulum dolor non, pulvinar mauris. Phasellus porttitor
+rhoncus augue at pretium. Vestibulum ante ipsum primis in faucibus orci luctus et ultrices
+posuere cubilia Curae; Mauris eu varius sapien. Integer pharetra mollis mi, vitae semper felis
+convallis id. Duis aliquam rutrum laoreet. Fusce eu ex metus.
+Etiam sit amet purus quis nisl sodales commodo. In et venenatis diam, et viverra enim.
+Curabitur vitae sem id neque interdum eleifend. Morbi eget est nec purus porta viverra a eget
+turpis. Orci varius natoque penatibus et magnis dis parturient montes, nascetur ridiculus mus.
+Fusce faucibus ante nec ante sollicitudin cursus. Nullam porttitor magna viverra facilisis
+pharetra. Nunc eget maximus augue. Fusce in elementum augue, non volutpat sem. Aliquam
+vel eleifend velit, ut vulputate mi.
+Nullam velit nulla, malesuada consequat leo et, finibus auctor magna. Curabitur accumsan, nibh
+et commodo molestie, odio mi auctor velit, eget porta tortor orci nec urna. Vivamus id massa
+bibendum, molestie felis ut, mollis dolor. Pellentesque habitant morbi tristique senectus et netus
+et malesuada fames ac turpis egestas. Vestibulum iaculis viverra dictum. Nullam quis congue
+ipsum, in convallis nulla. Nulla dictum lacus in dolor ultricies, vel posuere nisi ultrices. Morbi
+vestibulum facilisis ligula, eget finibus tortor tristique vitae. Mauris elementum, elit et vestibulum
+pulvinar, purus libero ornare nisl, eu ultrices diam ex ut nunc. Quisque id tincidunt eros. Ut quis
+vulputate urna, eu suscipit libero.
+Heading 2
+Heading 3

files/webviewer.pdf.txt

@@ -1,42 +1,3 @@
-A lower-quality library also encounters
-performance and memory issues, such as large
-documents with frustratingly long wait times for
-your users as well as complex documents that
-crash the viewer. This is often due to the absence
-of features such as PDF tiling, parallelization,
-and linearization that a more mature PDF SDK
-will incorporate.
-Some solutions (e.g., image servers) perform
-excellently when tested on a small number of
-documents and users but then inflict unexpected
-hidden costs when scaled up. When hundreds
-or thousands of users later view, mark up, comment
-on, and otherwise interact with (i.e.,scroll,
-pan, and zoom) documents, server resource and
-network data usage explodes. To maintain your
-desired UX, you have to pay higher fees or invest
-in more servers.
-The following types of documents have much
-more demanding rendering requirements:
-• CAD-based PDFs such as construction and
-engineering drawings with very large and
-complex designs.
-• Reports, textbooks, and marketing material
-using advanced PDF graphics such as shadings,
-gradients, soft masks, and patterns.
-• Geospatial maps with OCG layers that are
-switched off by default.
-• Pre-press documents which require an SDK
-with advanced color management features to
-print colors accurately.
-• High-speed accurate rendering (especially on
-native mobile apps and mobile browsers).
-• Context extraction of tables, text, etc. with
-document structure (e.g., text read order or
-table arrangement) in tact.
-To prevent crashes, slowness, and rendering
-issues from disrupting your UX, test functionality
-with the types of documents your users will work
-with. Also test a server-based solution at the
-anticipated load and usage.
-6
+6 Important Factors when
+Choosing a PDF Library
+ADAM PEZ

index.js

@@ -45,10 +45,7 @@ app.get('/optimize/:filename', (req, res) => {
   );
 
   if (ext !== '.pdf') {
-    res.statusCode = 500;
-    res.end(
-      `Only PDFs can be optimized. Cannot optimize file with extension: ${ext}.`,
-    );
+    throw `Only PDFs can be optimized. Cannot optimize file with extension: ${ext}.`;
   }
 
   const main = async () => {
@@ -85,10 +82,7 @@ app.get('/thumbnail/:filename', (req, res) => {
   const outputPath = path.resolve(__dirname, filesPath, `${filename}.png`);
 
   if (ext !== '.pdf') {
-    res.statusCode = 500;
-    res.end(
-      `Only PDFs can return a thumbnail. Cannot return a thumb for a file with extension: ${ext}.`,
-    );
+    throw `Only PDFs can return a thumbnail. Cannot return a thumb for a file with extension: ${ext}.`;
   }
 
   const main = async () => {
@@ -144,14 +138,12 @@ app.get('/textextract/:filename-:pagenumber', (req, res) => {
   const main = async () => {
     await PDFNet.initialize();
     try {
-      await PDFNet.startDeallocateStack();
       const pdfdoc = await PDFNet.PDFDoc.createFromFilePath(inputPath);
       await pdfdoc.initSecurityHandler();
       const page = await pdfdoc.getPage(pageNumber);
 
-      if (page.id === '0') {
-        console.log('Page not found.');
-        return 1;
+      if (!page) {
+        throw 'Page number is invalid.';
       }
 
       const txt = await PDFNet.TextExtractor.create();
@@ -163,11 +155,8 @@ app.get('/textextract/:filename-:pagenumber', (req, res) => {
       fs.writeFile(outputPath, text, (err) => {
         if (err) return console.log(err);
       });
-      await PDFNet.endDeallocateStack();
     } catch (err) {
-      console.log(err);
-      console.log(err.stack);
-      return 1;
+      throw err;
     }
   };
 
@@ -176,13 +165,9 @@ app.get('/textextract/:filename-:pagenumber', (req, res) => {
 
 const PDFNetEndpoint = (main, pathname, res) => {
   PDFNet.runWithCleanup(main)
-    .catch(function (error) {
-      res.statusCode = 500;
-      res.end(`Error : ${JSON.stringify(error)}.`);
-    })
-    .then(function () {
+    .then(() => {
       PDFNet.shutdown();
-      fs.readFile(pathname, function (err, data) {
+      fs.readFile(pathname, (err, data) => {
         if (err) {
           res.statusCode = 500;
           res.end(`Error getting the file: ${err}.`);
@@ -192,6 +177,10 @@ const PDFNetEndpoint = (main, pathname, res) => {
           res.end(data);
         }
       });
+    })
+    .catch((error) => {
+      res.statusCode = 500;
+      res.end(error);
     });
 };