Single File Code

Single File Code, or sfc, allows to execute NodeJS scripts and methods with its dependencies. defined in the script itself. Either via cli or via module

Instead of having a package.json file and installing the dependencies via npm commands, you can specify the dependencies in your script comments.

SFC will take care of installing the dependencies.

/**
 * @dependency lodash latest
 */
require('lodash').map([1,2,3,4], n => console.log(n))

/**
 * @dependency faker latest
 */
let fake = require('faker').fake('{{name.lastName}}, {{name.firstName}}')
console.log(fake)

It supports --watch for your development-phase things.

Installation

Use your terminal to install sfc as a globally availabe package.

npm i nodesfc -g

Cli usage

Usage: nodesfc [options] <file>

Options:
  -V, --version  output the version number
  -d, --dryrun   Removes node_modules and package-lock.json before installing dependencies.
  --debug        Enables debug messages.
  -w, --watch    Watch for changes in the file
  --noupdate     Opt-out of update version check
  -h, --help     display help for command

Example:
  $ nodesfc --watch example/file.js

Specifying dependencies:
  /**
   * @dependency lodash latest
   */

To get help, execute:

nodesfc -h

Library usage

You can invoke a JS file in two different ways.

Invoking an specific method (like in AWS Lambda)

This will return the method's result - as it is.

let lib = require('nodesfc')

let r = await lib.init({
  method: 'handler', // Name of the method to be executed
  methodArgs: ["hello", "world"], // List of parameters to apply
  file: './export-handler.js'
})

console.log(r)

// { firstParameter: 'hello', secondParameter: 'world' }

The init method returns a Promise with the method's result.

Executing an entine NodeJS script

This will return the full std output as an array.

require('nodesfc')
  .init({
    file: 'my_javascript_file.js', // File to execute
    env: { // Optional k->v pairs of custom environment variables
      CHARACTER: 'Jon Snow'
    }
  })
  .then(result => console.log({result}))

/*
  {
    "stdLines": [
      {
        "output": "1",
        "err": false,
        "date": "2019-08-14T11:47:21.821Z"
      },
      {
        "output": "2",
        "err": false,
        "date": "2019-08-14T11:47:21.821Z"
      },
      {
        "output": "3",
        "err": false,
        "date": "2019-08-14T11:47:21.821Z"
      },
      {
        "output": "4",
        "err": false,
        "date": "2019-08-14T11:47:21.821Z"
      },
      {
        "output": "Boyle, Alek",
        "err": false,
        "date": "2019-08-14T11:47:23.063Z"
      }
    ],
    "code": 0
  }
*/

The init method returns a Promise with an object with the properties:

• stdLines being an array of objects containing the STD outputs for both errors and logs. In the same order as they were triggered.
  • output string - the actual text logged
  • err boolean - determines if the log was sent to std-err or not
• code number - the execution exit code.

Contributing

Pull requests are welcome. For major changes, please open an issue first to discuss what you would like to change.

License

MIT