denode 🐉

Run your Deno code in Node.js!

Disclaimer ⚠️

Project is only proof of concept, many cases may not works. Pull requests and discussion are welcome!

How it works:

1. Bundle with Deno bundle absent replacement modules from deps section of config.
2. Babel code to support by specified node version.
3. Generate package.json with dependencies.
4. Create global variable Deno with wome std features (now only fs is supported).
5. Add calls of npm modules (see Dependencies replacement explanation section).

CLI

denode is available as cli tool

Usage

 deno run -A --unstable https://deno.land/x/denode/mod.ts function.ts ./bundle

Options

Configuration options

JSON file with next structure:

{
  "node": "12",
  "static": "src/static",
  "deps": {
    "some-npm-module": {
      "name": "some-npm-module",
      "npm": "1.1.1",
      "global": "someNpmModule",
      "path": ".someNpmModule"
    },
    "https://deno.land/std/fs/mod.ts": {
      "std": "fs"
    }
  }
}

interface IConfig {
  node: string;         // Target Node.js version;
  static?: string;      // Static folder path. Denode will copy all files into #BUNDLE_PATH#;
  deps?: {              // Dependencies, that should be replaced in target bundle (module name from import_map.json or URL);
    [module: string]: {
      name?: string;    // module name ( in result package.json );
      npm?: string;     // npm version ( in result package.json );
      global?: string;  // global variable name;
      path?: string;    // global variable path from root module;
      std?: string;     // Deno std module stub. Now only 'fs' is supported;
    }
  }
}

Dependencies replacement explanation

In some cases, there is a need in replace some module in Deno with Node (npm) similiar one or replace Deno native api with Node native.

npm modules

⚠️ Import throwugh global variables are only support for now. No code of module will delivery to result bundle.

Example: Code in Deno:

import 'someLib';

declare global {
  var Lib: any;
}

Lib.doSomeJob();
...

To replace it with npm module you should add it to bundle_config.json in deps section:

"deps": {
  "someLib": {
     "name": "someLib",
     "npm": "^1.1.1"
  }
}

This will add "someLib": "^1.1.1" in package.json and will add in result bundle code (in start of it):

  require('someLib'); // just require module

“global” option:

"deps": {
  "someLib": {
     "name": "someLib",
     "npm": "^1.1.1",
     "global": "globalSomeLib"
  }
}

Will become:

const someLibModule = require('someLib');
global.globalSomeLib = someLibModule; // add global variable

“path” and “global” option:

"deps": {
  "someLib": {
     "name": "someLib",
     "npm": "^1.1.1",
     "global": "globalSomeLib",
     "path": ".lib"
  }
}

Will become:

const someLibModule = require('someLib');
global.globalSomeLib = someLibModule.lib; // path added

std modules

Now only fs module is supported

Example: This code will work in both Deno and Node:

import * as fs from "https://deno.land/std@0.69.0/fs/mod.ts";

console.log(fs.existsSync('/some/path'));

Config:

"deps": {
  "https://deno.land/std@0.69.0/fs/mod.ts": {
     "std": "fs"
  }
}