MediEval

MediEval is a library that lets you evaluate code in several language runtimes. MediEval functionality is exposed in two convenient ways:

1. Command line executable, called 'medieval'
2. Node.js APIs, using require('medieval').

MediEval can be used to create code evaluators like those used at CodeAcademy, TestDome and repl.it.

MediEval owes many thanks to Docker, on which it runs.

Runtimes currently supported:

• node
• ruby
• python

Thankware

MediEval is thankware; which means I don't want any money for the effort I put into it...

...but I LOVE getting paid in thank-you's!

Ways to thank me:

1. Twitter: Help spread the word with #hashtags and @mentions!
2. Twitter: Follow me. My twitter handle is @monarchwadia
3. Github: Star MediEval on Github

Restrictions

Currently (mostly because of the fact that the project is quite new at this moment), only Docker on Linux is supported. But this can change! Let me know that you like MediEval! if enough people are using MediEval, I can absolutely add support for Windows and MacOS.

Installation

0. Only supported on Linux. It might not work on Windows or MacOS.
1. Ensure that you have Docker installed.
2. Make sure that your user can use Docker without sudo.
3. npm install -g medieval

NPM Instructions

MediEval relies on Promises to return the results of your evaluation.

Note that .catch is only used to catch unexpected errors on the library level and below. Should the evaluation fail (for example, because of an exception being thrown by the code being evaluated), then that will be considered a success, and the response will return with stdout, stderr and statusCode inside the then function.

The response comes in the following format:

// Example output
{
    "stdout": "Hello World\n",
    "stderr": "",
    "statusCode": 0
}

const medieval = require('medieval');

// Node.js
let nodeScript = 'console.log("Hello World");'
medieval.node(nodeScript)
  .then({stdout, stderr, statusCode} => {
    console.log({stdout, stderr, statusCode});  
  })
  .catch(err => {
    console.log(err);
  });

// Python
let pythonScript = 'print("Hello World")'
  medieval.python(pythonScript)
    .then({stdout, stderr, statusCode} => {
      console.log({stdout, stderr, statusCode});  
    })
    .catch(err => {
      console.log(err);
    });

Command Line Instructions

Usage

   medieval 0.0.2 
     
   USAGE

     medieval <command> [options]

   COMMANDS

     node <script>        Evaluates node code                
     ruby <script>        Evaluates ruby code                
     python <script>      Evaluates python code              
     serve                Runs the evaluator in server mode  
     help <command>       Display help for a specific command

   GLOBAL OPTIONS

     -h, --help         Display help                                      
     -V, --version      Display version                                   
     --no-color         Disable colors                                    
     --quiet            Quiet mode - only displays warn and error messages
     -v, --verbose      Verbose mode - will also output debug messages    

Examples

# In your terminal
medieval node "console.log('Hello ' + 'World')"
> Hello World
medieval python "print('Hello ' + 'World')"
> Hello World
medieval ruby "puts 'Hello ' + 'World'"
> Hello World

Server Mode

MediEval is capable of running a standalone Express server.

medieval serve
> MediEval server listening on port 1337

You can specify a custom port by passing in the --port option

medieval serve --port 3000
> MediEval server listening on port 3000

There is only one endpoint, POST /, which has the following API contract:

VERB:    POST

PATH:    /

PAYLOAD:
  code: The code to evaluate. Required.
  runtime: The runtime to invoke (ruby, node, python...). Required.

RESPONSE:
  stdout: The stdout output of the invocation
  stderr: The stderr output of the invocation
  statusCode: The status code of the process exit

Here is an example of a payload and a response.

EXAMPLE PAYLOAD : 
{
  "code": "console.log('Hello World')",
  "runtime": "node"
}

ExAMPLE RESPONSE:
{
    "stdout": "Hello World\n",
    "stderr": "",
    "statusCode": 0
}