Allow custom qpdf binary

README.md

@@ -7,7 +7,7 @@
 [![npm](https://img.shields.io/npm/dm/node-qpdf)](https://www.npmjs.com/package/node-qpdf2)
 [![qpdf 11+](https://img.shields.io/badge/dependencies-qpdf-green)](https://github.com/qpdf/qpdf)
 
-A very simple wrapper for [qpdf](https://github.com/qpdf/qpdf) which is performs content-preserving transformations on PDF files. It includes encrypting and decrypting PDF files with AES 256, AES 128, RC4 (128 & 40) encryption algorithms. This is a fork of [nrhirani/node-qpdf](https://github.com/nrhirani/node-qpdf), adding Promises and Types, and is kept mostly up to date with `qpdf`.
+A very simple wrapper for [qpdf](https://github.com/qpdf/qpdf) which performs content-preserving transformations on PDF files. It includes encrypting and decrypting PDF files with AES 256, AES 128, RC4 (128 & 40) encryption algorithms. This is a fork of [nrhirani/node-qpdf](https://github.com/nrhirani/node-qpdf), adding `Promises` and `Types`, and is kept mostly up to date with `qpdf`.
 
 ## Dependencies
 
@@ -16,94 +16,119 @@ A very simple wrapper for [qpdf](https://github.com/qpdf/qpdf) which is performs
 
 ## Installation
 
-1. Install qpdf:
-   - Download [qpdf](https://github.com/qpdf/qpdf/releases)
-2. Install node-qpdf:
-   ```
-   npm install node-qpdf2
-   ```
+1. Install [qpdf](https://github.com/qpdf/qpdf/releases):
+2. Install `node-qpdf2`:
 
-## Serverless?
+```bash
+  npm install node-qpdf2
+  # or
+  yarn add node-qpdf2
+```
 
-This package can be uses on serverless platforms by using your vendor's layers functionality. Use the zip release from `qpdf` as the layer. For example, `qpdf-11.1.0-bin-linux-x86_64.zip` can be directly uploaded as a layer, and has been tested using Amazon Lambda.
+## Serverless?
 
-## Encryption
+This package can be used on serverless platforms and has been tested on `Amazon Lambda` and `Google Cloud Functions`. 
 
-You can encrypt your PDF by following:
+### Amazon Lambda
+Download latest `qpdf-XX.X.X-bin-linux-x86_64.zip` release from `qpdf` then directly upload it as a [layer](https://docs.aws.amazon.com/lambda/latest/dg/chapter-layers.html).
 
-```
-import { encrypt } from "node-qpdf2";
+### Google Cloud Functions
+Download latest `qpdf-XX.X.X-bin-linux-x86_64.zip` release then extract it's content where functions entry point (generally `index.js`) is:
 
-const pdf = {
-  input: "./test/example.pdf",
-  output: "/tmp/encrypted.pdf",
-  password: "1234",
+```bash
+# package.json
+{
+  ...
+  # entry point
+  "main": "build/index.js",
+  ...
 }
 
-await encrypt(pdf);
+# directory structure
+/root_dir
+  /build
+    # entry point
+    /index.js 
+    /other files...
+    # you can rename qpdf folder to whatever you want
+    /qpdf_dir 
+      # zip content
+      /bin
+      /lib 
+  /src
+    /index.ts
+    /other files...
 ```
 
-### Options for Encryption
+Then provide a `qpdfPath` pointing to `bin` folder inside `qpdf` directory:
+```bash 
+import path from "path";
 
-Please see [src/encrypt.ts](https://github.com/Sparticuz/node-qpdf2/blob/master/src/encrypt.ts#L9) for the latest options, as well as [QPDF's documentation](https://qpdf.readthedocs.io/en/stable/cli.html#encryption) for information on what each restriction does.
+const pdf = {
+  qpdfPath: path.join( process.cwd(), 'qpdf_dir/bin' ),
+  ... other props
+}
+```
 
-### Examples
+## Encryption
 
-#### Render and Save:
+You can encrypt your PDF by following:
 
-```
+```bash
 import { encrypt } from "node-qpdf2";
 
 const options = {
-    input: "./test/example.pdf",
-    keyLength: 128,
-    output: "/tmp/encrypted.pdf",
-    password: 'YOUR_PASSWORD_TO_ENCRYPT',
-    restrictions: {
-        print: 'low',
-        useAes: 'y'
-    }
+  input: "./test/example.pdf",
+  output: "/tmp/encrypted.pdf",
+  password: 'ENCRYPTION_PASSWORD',
+  restrictions: {
+    print: 'low',
+    useAes: 'y'
+  }
 }
 
 await encrypt(options);
 ```
 
+### Encryption options
+
+Please see [src/encrypt.ts](https://github.com/Sparticuz/node-qpdf2/blob/master/src/encrypt.ts#L9) for the all available options, as well as [qpdf's documentation](https://qpdf.readthedocs.io/en/stable/cli.html#encryption) for informations about each restriction prop.
+
 ## Decryption
 
 You can decrypt your PDF by following:
 
-```
+```bash
 import { decrypt } from "node-qpdf2";
 
 const options = {
   input: "/tmp/encrypted.pdf",
   output: "/tmp/decrypted.pdf",
-  password: "YOUR_PASSWORD_TO_DECRYPT_PDF",
+  password: "ENCRYPTION_PASSWORD",
 }
 
 await decrypt(options);
 ```
 
-## PDF Encryption info
+## Encryption info
 
-You can retrieve encryption information using the info function. This function will return a Promise<string>. See [here](https://qpdf.readthedocs.io/en/stable/cli.html#option-show-encryption) for more information.
+You can retrieve encryption information using the info function. This function will return a `Promise<string>`. See [here](https://qpdf.readthedocs.io/en/stable/cli.html#option-show-encryption) for more information.
 
-```
+```bash
 import { info } from "node-qpdf2";
 
 const options = {
   input: "/tmp/encrypted.pdf",
-  password: "FILE_PASSWORD",
+  password: "ENCRYPTION_PASSWORD",
 }
 
 console.log(await info(options));
 ```
-
-If the file is not encrypted, the result will be "File is not encrypted".
+If file is not encrypted, the result will be `File is not encrypted`.
 
 ## Coverage
 
-| File       | % Stmts | % Branch | % Funcs | % Lines | Uncovered Line #s |
+| File       | % Stmts | % Branch | % Funcs | % Lines | Uncovered Lines   |
 | ---------- | ------- | -------- | ------- | ------- | ----------------- |
 | All files  | 100     | 100      | 100     | 100     |
 | decrypt.ts | 100     | 100      | 100     | 100     |

src/decrypt.ts

@@ -2,6 +2,8 @@ import execute from "./spawn.js";
 import { fileExists } from "./utils.js";
 
 export interface DecryptSettings {
+  /** Optional - Path to custom qpdf binary */
+  qpdfPath?: string
   /** The path for the encrypted pdf */
   input: string;
   /** The path for the decrypted pdf */
@@ -36,5 +38,5 @@ export const decrypt = async (payload: DecryptSettings): Promise<Buffer> => {
     callArguments.push("-");
   }
 
-  return execute(callArguments);
+  return execute(callArguments, payload.qpdfPath);
 };

src/encrypt.ts

@@ -7,6 +7,8 @@ const EncryptDefaults = {
 };
 
 export interface EncryptOptions {
+  /** Optional - Path to custom qpdf binary */
+  qpdfPath?: string
   /** The location of the unencrypted pdf file */
   input: string;
   /**
@@ -76,9 +78,9 @@ export const encrypt = async (userPayload: EncryptOptions): Promise<Buffer> => {
 
   const callArguments = [];
 
-  // If the keyLength is 40, `--allow-weak-crypto` needs to be specified before `--encrypt`.
+  // If the keyLength is not 256, `--allow-weak-crypto` needs to be specified before `--encrypt`.
   // This is required for qpdf 11+.
-  if (payload.keyLength === 40) callArguments.push("--allow-weak-crypto");
+  if (payload.keyLength !== 256) callArguments.push("--allow-weak-crypto");
 
   callArguments.push("--encrypt");
 
@@ -136,5 +138,5 @@ export const encrypt = async (userPayload: EncryptOptions): Promise<Buffer> => {
     callArguments.push("-");
   }
   // Execute command and return stdout for pipe
-  return execute(callArguments);
+  return execute(callArguments, payload.qpdfPath);
 };

src/info.ts

@@ -2,6 +2,8 @@ import execute from "./spawn.js";
 import { fileExists } from "./utils.js";
 
 export interface InfoSettings {
+  /** Optional - Path to custom qpdf binary */
+  qpdfPath?: string
   /** The path for the encrypted pdf */
   input: string;
   /** The password for the encrypted pdf */
@@ -27,7 +29,7 @@ export const info = async (payload: InfoSettings): Promise<string> => {
   // Input file path
   callArguments.push(payload.input);
 
-  const result = await execute(callArguments);
+  const result = await execute(callArguments, payload.qpdfPath);
 
   return result.toLocaleString().trim();
 };

src/spawn.ts

@@ -3,9 +3,11 @@
 
 import { spawn } from "node:child_process";
 
-export default (callArguments: string[]): Promise<Buffer> =>
+export default (callArguments: string[], qpdfPath?:string): Promise<Buffer> =>
   new Promise((resolve, reject) => {
-    const process = spawn("qpdf", callArguments);
+    const process = spawn(qpdfPath? "./qpdf" :"qpdf", callArguments, {
+      cwd: qpdfPath
+    });
     const stdout: string[] = [];
     const stderr: string[] = [];
     process.stdout.on("data", (data) => {