Fix formidable upload issue, fix error handling, do structural refactor

main.js

@@ -1,24 +1,30 @@
 'use strict';
-
-const config = require('./config');
-
-const cors = require('cors');
 const express = require('express');
+const cors = require('cors');
 
 const app = express();
 
+const config = require('./config');
+
 const {version} = require('./package.json');
+const {debug} = require('./src/handlers');
+const {errorHandler} = require('./src/handlers/errors');
 
-const pdfRouter = require('./src/pdf/router');
+const pdfRouter = require('./src/router');
+const debugScopes = require('./src/debug-scopes');
 
 app.use(cors());
 
+app.use(debug(debugScopes.DEFAULT));
+
 app.get('/version', async (__req, res) => {
   res.send({version});
 });
 
 app.use('/pdf', pdfRouter);
 
+app.use(errorHandler);
+
 app.listen(config.port, () => {
   // eslint-disable-next-line no-console
   console.log(`PDF Libs listening on port: ${config.port}`);

src/debug-scopes.js

@@ -0,0 +1,9 @@
+'use strict';
+
+const debugScopes = {
+  DEFAULT: 'pdfLibs.default',
+  CONVERT_TO_HTML: 'pdfLibs.html',
+  FORMFIELDS: 'pdfLibs.formfields'
+};
+
+module.exports = debugScopes;

src/errors/index.js

@@ -0,0 +1,5 @@
+'use strict';
+
+module.exports = {
+  ...require('./validation-error')
+};

src/errors/validation-error.js

@@ -0,0 +1,16 @@
+'use strict';
+
+class ValidationError extends Error {
+  constructor (message, errors) {
+    super(message);
+    this.errors = errors;
+    this.statusCode = 400;
+  }
+
+  withStatus (statusCode) {
+    this.statusCode = statusCode;
+    return this;
+  }
+}
+
+module.exports = {ValidationError};

src/pdf/middleware/cleanup.js → src/handlers/cleanup.js

@@ -2,7 +2,8 @@
 
 const fs = require('fs/promises');
 const _ = require('lodash');
-module.exports = (req, res, next) => {
+
+const cleanup = (req, res, next) => {
   res.on('finish', () => {
     if (!req.cleanup || !req.cleanup.length) {
       return;
@@ -20,3 +21,5 @@ module.exports = (req, res, next) => {
   });
   return next();
 };
+
+module.exports = {cleanup};

src/handlers/debug.js

@@ -0,0 +1,15 @@
+'use strict';
+
+const logDebug = require('debug');
+
+const debug = (namespace) => {
+  const log = logDebug(namespace);
+  return (req, __res, next) => {
+    req.debug = (msg) => {
+      log(`${msg}`);
+    };
+    next();
+  };
+};
+
+module.exports = {debug};

src/handlers/errors.js

@@ -0,0 +1,13 @@
+'use strict';
+
+const {ValidationError} = require('../errors');
+
+const errorHandler = (err, req, res, __next) => {
+  req.debug?.(`Error: ${err.message || err}`);
+  if (err instanceof ValidationError) {
+    return res.status(err.statusCode).send(err.message);
+  }
+  res.status(500).send(err.message ?? err);
+};
+
+module.exports = {errorHandler};

src/handlers/get-file-from-formdata.js

@@ -0,0 +1,22 @@
+'use strict';
+
+const formidable = require('formidable');
+const {ValidationError} = require('../errors');
+
+const getFileFromFormData = (req, __res, next) => {
+  const form = new formidable.IncomingForm();
+  req.cleanup = [];
+  form.parse(req, async (err, __, files) => {
+    if (err) {
+      return next(new ValidationError(err?.message ?? err));
+    }
+    if (!files.pdf) {
+      return next(new ValidationError('No files were uploaded'));
+    }
+    req.filePath = files.pdf[0].filepath;
+    req.cleanup.push(req.file);
+    next();
+  });
+};
+
+module.exports = {getFileFromFormData};

src/handlers/index.js

@@ -0,0 +1,8 @@
+'use strict';
+
+module.exports = {
+  ...require('./pdf'),
+  ...require('./get-file-from-formdata'),
+  ...require('./cleanup'),
+  ...require('./debug'),
+};

src/pdf/middleware/convert-to-html.js → src/handlers/pdf/convert-to-html.js

@@ -4,7 +4,7 @@ const path = require('path');
 const {v4: uuid} = require('uuid');
 const tmpdir = require('os').tmpdir();
 
-const {generateHtml} = require('../services/convert-to-html');
+const {generateHtml} = require('../../services/pdf/convert-to-html');
 const {htmlGenerationTimeoutConfig} = require('../../../config');
 
 const convertToHtml = async (req, res, next) => {
@@ -27,7 +27,7 @@ const convertToHtml = async (req, res, next) => {
   }
   catch (err) {
     return req.optimizedPdf
-      ? res.status(500).send(err)
+      ? next(err)
       : next();
   }
   return res.sendFile(outputPath, (err) => {
@@ -37,4 +37,4 @@ const convertToHtml = async (req, res, next) => {
   });
 };
 
-module.exports = convertToHtml;
+module.exports = {convertToHtml};

src/handlers/pdf/get-formfields.js

@@ -0,0 +1,15 @@
+'use strict';
+
+const {extractFormfields} = require('../../services/pdf/formfields');
+
+const getFormfields = async (req, res, next) => {
+  try {
+    const jsonOutput = await extractFormfields(req.filePath);
+    res.json(jsonOutput);
+  }
+  catch (err) {
+    return next(err);
+  }
+};
+
+module.exports = {getFormfields};

src/pdf/middleware/hide-formfields.js → src/handlers/pdf/hide-formfields.js

@@ -1,11 +1,12 @@
 'use strict';
 
-const config = require('../../../config');
-const {exec} = require('../utils');
 const path = require('path');
 const os = require('os');
 const {v4: uuid} = require('uuid');
 
+const config = require('../../../config');
+const {exec} = require('../../utils');
+
 const hideFormfields = async (req, __res, next) => {
   const outputPath = path.join(os.tmpdir(), `${uuid()}.pdf`);
   req.cleanup.push(outputPath);
@@ -15,4 +16,4 @@ const hideFormfields = async (req, __res, next) => {
   next();
 };
 
-module.exports = hideFormfields;
+module.exports = {hideFormfields};

src/handlers/pdf/index.js

@@ -0,0 +1,8 @@
+'use strict';
+
+module.exports = {
+  ...require('./get-formfields'),
+  ...require('./optimize-pdf'),
+  ...require('./hide-formfields'),
+  ...require('./convert-to-html'),
+};

src/pdf/middleware/optimize-pdf.js → src/handlers/pdf/optimize-pdf.js

@@ -3,23 +3,23 @@
 const os = require('os');
 const path = require('path');
 const {v4: uuid} = require('uuid');
-const {psToPdf} = require('../services/convert-to-html');
+const {psToPdf} = require('../../services/pdf/convert-to-html');
 
-const optimizePdf = (req, res, next) => {
+const optimizePdf = (req, __res, next) => {
   req.debug('Optimizing PDF');
   const outputPath = path.join(os.tmpdir(), `${uuid()}.pdf`);
   req.cleanup.push(outputPath);
   psToPdf(req.filePath, outputPath, (err, filePath) => {
     if (err) {
-      res.status(500).send(err);
+      return next(err);
     }
     if (!filePath) {
-      res.status(500).send('Error when optimizing PDF file');
+      return next(new Error('Optimized PDF not found'));
     }
     req.filePath = filePath;
     req.optimizedPdf = true;
     next();
   });
 };
 
-module.exports = optimizePdf;
+module.exports = {optimizePdf};

src/pdf/router.js → src/router.js

@@ -1,6 +1,7 @@
 'use strict';
 
 const r = require('express').Router();
+const debugScopes = require('./debug-scopes');
 
 const {
   getFileFromFormData,
@@ -9,14 +10,13 @@ const {
   getFormfields,
   cleanup,
   debug
-} = require('./middleware');
+} = require('./handlers');
 
-r.use(debug('pdfLibs'));
 r.use(cleanup);
 r.use(getFileFromFormData);
 
 r.post('/convertToHtml',
-  debug('pdfLibs.html'),
+  debug(debugScopes.CONVERT_TO_HTML),
   // hideFormfields,
   convertToHtml,
   optimizePdf,
@@ -26,7 +26,7 @@ r.post('/getFormfields', debug('pdfLibs.formfields'), getFormfields);
 
 // DEPRECATED PATHS
 r.post('/pdf2html',
-  debug('pdfLibs.html'),
+  debug(debugScopes.FORMFIELDS),
   // hideFormfields,
   convertToHtml,
   optimizePdf,

src/pdf/services/convert-to-html/generate-html.js → src/services/pdf/convert-to-html/generate-html.js

@@ -1,7 +1,7 @@
 'use strict';
 
 const {pdf2htmlexPath} = require('../../../../config');
-const {exec} = require('../../utils');
+const {exec} = require('../../../utils');
 
 const generateHtml = async (filePath, toFile, params, commands, timeout) => {
   const {zoom, dpi} = params;
@@ -24,4 +24,4 @@ const generateHtml = async (filePath, toFile, params, commands, timeout) => {
   await exec(`${pdf2htmlexPath} ${args.join(' ')}`, {timeout});
 };
 
-module.exports = generateHtml;
+module.exports = {generateHtml};