feat: add canBeConvertedToPDF method

Author: vladholubiev

package.json

@@ -35,7 +35,10 @@
   ],
   "dependencies": {
     "@shelf/aws-lambda-brotli-unpacker": "0.0.2",
-    "del": "4.1.1"
+    "@shelf/is-audio-filepath": "0.0.3",
+    "del": "4.1.1",
+    "is-image": "3.0.0",
+    "is-video": "1.0.1"
   },
   "devDependencies": {
     "@babel/cli": "7.4.4",

readme.md

@@ -18,12 +18,16 @@ Follow the instructions on how to add a lambda layer in [that repo](https://gith
 ## Usage
 
 ```js
-const {convertTo} = require('@shelf/aws-lambda-libreoffice');
+const {convertTo, canBeConvertedToPDF} = require('@shelf/aws-lambda-libreoffice');
 
 module.exports.handler = async () => {
   // assuming there is a document.docx file inside /tmp dir
   // original file will be deleted afterwards
 
+  if (!canBeConvertedToPDF('document.docx')) {
+    return false;
+  }
+
   return convertTo('document.docx', 'pdf'); // returns /tmp/document.pdf
 };
 ```

src/convert.ts

@@ -0,0 +1,43 @@
+import {unpack} from '@shelf/aws-lambda-brotli-unpacker';
+import {execSync} from 'child_process';
+import {cleanupTempFiles} from './cleanup';
+import {getConvertedFilePath} from './logs';
+
+export const defaultArgs = [
+  '--headless',
+  '--invisible',
+  '--nodefault',
+  '--view',
+  '--nolockcheck',
+  '--nologo',
+  '--norestore'
+];
+
+const INPUT_PATH = '/opt/lo.tar.br';
+const OUTPUT_PATH = '/tmp/instdir/program/soffice';
+
+// see https://github.com/alixaxel/chrome-aws-lambda
+export async function getExecutablePath(): Promise<string> {
+  return unpack({inputPath: INPUT_PATH, outputPath: OUTPUT_PATH});
+}
+
+/**
+ * Converts a file in /tmp to the desired file format
+ * @param {String} filename Name of the file to convert located in /tmp directory
+ * @param {String} format File format to convert incoming file to
+ * @return {Promise<String>} Absolute path to the converted file
+ */
+export async function convertTo(filename: string, format: string): Promise<string> {
+  cleanupTempFiles();
+
+  const binary = await getExecutablePath();
+
+  const logs = execSync(
+    `cd /tmp && ${binary} ${defaultArgs.join(' ')} --convert-to ${format} --outdir /tmp ${filename}`
+  );
+
+  execSync(`rm /tmp/${filename}`);
+  cleanupTempFiles();
+
+  return getConvertedFilePath(logs.toString('utf8'));
+}

src/index.ts

@@ -1,43 +1,2 @@
-import {unpack} from '@shelf/aws-lambda-brotli-unpacker';
-import {execSync} from 'child_process';
-import {cleanupTempFiles} from './cleanup';
-import {getConvertedFilePath} from './logs';
-
-export const defaultArgs = [
-  '--headless',
-  '--invisible',
-  '--nodefault',
-  '--view',
-  '--nolockcheck',
-  '--nologo',
-  '--norestore'
-];
-
-const INPUT_PATH = '/opt/lo.tar.br';
-const OUTPUT_PATH = '/tmp/instdir/program/soffice';
-
-// see https://github.com/alixaxel/chrome-aws-lambda
-export async function getExecutablePath(): Promise<string> {
-  return unpack({inputPath: INPUT_PATH, outputPath: OUTPUT_PATH});
-}
-
-/**
- * Converts a file in /tmp to the desired file format
- * @param {String} filename Name of the file to convert located in /tmp directory
- * @param {String} format File format to convert incoming file to
- * @return {Promise<String>} Absolute path to the converted file
- */
-export async function convertTo(filename: string, format: string): Promise<string> {
-  cleanupTempFiles();
-
-  const binary = await getExecutablePath();
-
-  const logs = execSync(
-    `cd /tmp && ${binary} ${defaultArgs.join(' ')} --convert-to ${format} --outdir /tmp ${filename}`
-  );
-
-  execSync(`rm /tmp/${filename}`);
-  cleanupTempFiles();
-
-  return getConvertedFilePath(logs.toString('utf8'));
-}
+export * from './convert';
+export * from './validations';

src/validations.test.ts

@@ -0,0 +1,16 @@
+import {canBeConvertedToPDF} from './validations';
+
+describe('canBeConvertedToPDF', () => {
+  it.each`
+    filename        | expected
+    ${'image.jpg'}  | ${false}
+    ${'image.mp4'}  | ${false}
+    ${'image.mp3'}  | ${false}
+    ${'image.wav'}  | ${false}
+    ${'image.chm'}  | ${false}
+    ${'image.docx'} | ${true}
+    ${'image.pdf'}  | ${true}
+  `('should return $expected for filename $filename', ({filename, expected}) => {
+    expect(canBeConvertedToPDF(filename)).toEqual(expected);
+  });
+});

src/validations.ts

@@ -0,0 +1,9 @@
+import isAudio from '@shelf/is-audio-filepath';
+import isVideo from 'is-video';
+import isImage from 'is-image';
+
+export function canBeConvertedToPDF(filename: string): boolean {
+  return (
+    !isImage(filename) && !isVideo(filename) && !isAudio(filename) && !filename.endsWith('.chm')
+  );
+}