Here’s a step-by-step guide to build a Node.js-based bash script for production and package it as a standalone executable:

Step 1: Set Up the Project

1. Create a New Directory:

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mkdir node-bash
cd node-bash

1. Initialize a Node.js Project:

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npm init -y

1. This creates a package.json file with default values.

Step 2: Write the Script

1. Create a file named node-bash.js in the project directory:

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touch node-bash.js

1. Add the following code to node-bash.js:

javascript

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#!/usr/bin/env node

const readline = require("readline");
const { exec } = require("child_process");

const rl = readline.createInterface({
    input: process.stdin,
    output: process.stdout,
    prompt: "node-bash> ",
});

console.log("Welcome to Node.js Bash! Type 'exit' to quit.\n");

rl.prompt();

rl.on("line", (line) => {
    const command = line.trim();

    if (command === "exit") {
        console.log("Exiting Node.js Bash. Goodbye!");
        rl.close();
        return;
    }

    exec(command, (err, stdout, stderr) => {
        if (err) {
            console.error(`Error: ${err.message}`);
        } else {
            if (stdout) console.log(stdout);
            if (stderr) console.error(stderr);
        }
        rl.prompt();
    });
});

rl.on("close", () => {
    console.log("Shell session closed.");
    process.exit(0);
});

1. Add execute permission to the file:

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chmod +x node-bash.js

Step 3: Configure package.json

1. Open package.json and update it to include a bin field:

json

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{
  "name": "node-bash",
  "version": "1.0.0",
  "description": "A simple Node.js-based bash shell",
  "main": "node-bash.js",
  "bin": {
    "node-bash": "./node-bash.js"
  },
  "author": "Your Name",
  "license": "MIT",
  "dependencies": {}
}

1. Install dependencies:

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npm install readline

Step 4: Link the Script Locally

1. Link the package globally for testing:

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npm link

1. Run the script using the node-bash command:

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node-bash

You should see the interactive bash shell prompt:

plaintext

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Welcome to Node.js Bash! Type 'exit' to quit.

node-bash>

Step 5: Package as a Standalone Executable

1. Install pkg globally:

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npm install -g pkg

1. Update package.json to specify pkg targets:

json

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{
  "pkg": {
    "scripts": "node-bash.js",
    "targets": ["node16-linux-x64", "node16-macos-x64", "node16-win-x64"]
  }
}

1. Run pkg to create executables:

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pkg .

This will generate binaries for Linux, macOS, and Windows in the current directory. Files will be named something like:

• node-bash-linux
• node-bash-macos
• node-bash-win.exe

Step 6: Test the Executable

1. Test the executable on your platform:

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./node-bash-linux      # Linux
./node-bash-macos      # macOS
./node-bash-win.exe    # Windows

1. Confirm it behaves like the original script.

Step 7: Distribute Your Script

1. Prepare Documentation: Add a README.md file explaining usage.
2. Share Executables: Distribute the binaries for different platforms.

Optional Enhancements

• Add support for environment variables.
• Include custom commands or scripts.
• Handle complex shell features like piping (|) or chaining (&&, ||).