C# JavaScript Runner

This is a C# .NET Core project that shows usage of ClearScript V8 and Jint engines to run JavaScript code, using also other JavaScript libraries (as Node.js @hapi/formula etc).

Code is MIT licensed as ClearScript.

Highlights:

• starting from some barebone code that mimic the functionality of require/CommonJs and his explanation I adapted it for this project (myrequire.js) to use real and virtual fs, to append the ./lib search path and the .js extension when missing, etc
• implemented optional use of Base64 encoded zip files to store an entire folder of Js files and libraries in a single C# string. Working tests and assets provided.
• built a virtual filesystem (using simply a dictionary inside the scripting context) to intercept requests of files stored in memory
• wrote a simple JavaScript filesystem API layer that calls Node.js and C# methods to be able to read/write a file without worrying if the script is executed in memory or against a real fs, from ClearScript or Node. For security purposes the C# code doesn't allow any writing in the real filesystem above the scriptsPath

When possible I used TypeScript, to allow debug/static typing.

Interesting files

Scripting.Js.v1 project

Interesting files in the core library:

• JavaScript code runner
• scripting context implementing the virtual filesystem (InMemoryFs dictionary) and the methods called by the JavaScript custom filesystem API layer ReadFile, AppendFile, DeleteFile and Exists. For security purposes no writing is allowed in the real filesystem above the scriptsPath
• object to store the JavaScript scripts in memory (plain text, Base64 encoded text file or Zip file)

Scripting.JsScripts.v1

Interesting JavaScript files:

• main JavaScript file used to test require, filesystem and external libraries
• custom require
• custom filesystem API layer
• flag file generated for testing purposes and sample library to test exports
• other files in the lib folder are external JavaScript libraries, adapted for execution with ES5 engines if needed

Scripting.Tests

Interesting tests files:

• tests of InMemoryFiles (Zip) and JavaScript stored in a real filesystem; tested ES6 code with ClearScript and ES5 with Jint
• tests of Main.js script with both ClearScript and Node.js exe. Node.js exe path can be set in TestSettings