npm package: @log4js-node/sandboxed-module
Description: A sandboxed Node.js module loader that lets you inject dependencies into your modules.
Author: Felix Geisendörfer
Latest version: 2.2.1

# sandboxed-module

[![Build Status](https://secure.travis-ci.org/log4js-node/node-sandboxed-module.png)](http://travis-ci.org/log4js-node/node-sandboxed-module)

NOTE: this is a fork of [felixge's original](https://github.com/felixge/node-sandboxed-module), that doesn't seem to be maintained at the moment. If felixge's starts to be maintained again, this module will be deprecated.

A sandboxed node.js module loader that lets you inject dependencies into your
modules.

## Installation

``` bash
npm install @log4js-node/sandboxed-module
```

## Usage

``` javascript
var SandboxedModule = require('sandboxed-module');
var user = SandboxedModule.require('./user', {
  requires: {'mysql': {fake: 'mysql module'}},
  globals: {myGlobal: 'variable'},
  locals: {myLocal: 'other variable'},
});
```

## What to do with this

This module is intended to ease dependency injection for unit testing. However,
feel free to use it for whatever crimes you can think of.

## API

### SandboxedModule.load(moduleId, [options])

Returns a new `SandboxedModule` where `moduleId` is a regular module path / id
as you would normally pass into `require()`. The new module will be loaded in
its own v8 context, but otherwise have access to the normal node.js
environment.

`options` is an optional object that can be used to inject any of the
following:

* `requires:` An object containing `moduleId`s and the values to inject for
  them when required by the sandboxed module. This does not affect children
  of the sandboxed module.
* `globals:` An object of global variables to inject into the sandboxed module.
* `locals:` An object of local variables to inject into the sandboxed module.
* `sourceTransformers:` An object of named functions to transform the source code of
the sandboxed module's file (e.g. transpiler language, code coverage).
* `singleOnly:` If false, modules that are required by the sandboxed module will not
be sandboxed. By default all modules required by the sandboxedModule will be sandboxed
using the same options that were used for the original sandboxed module.
* `sourceTransformersSingleOnly:` If false, the source transformers will not be run against
modules required by the sandboxed module. By default it will take the same value as
`singleOnly`.
* `ignoreMissing:` If true, injected modules will not be required to have a corresponding file
on the file system. By default this is false.

### SandboxedModule.require(moduleId, [options])

Identical to `SandboxedModule.load()`, but returns `sandboxedModule.exports`
directly.

### SandboxedModule.configure(options)

Sets options globally across all uses of `SandboxedModule.load()` and
`SandboxedModule.require()`. This way, a commonly needed require, global, local,
or sourceTransformer can be specified once across all sandboxed modules.

### SandboxedModule.registerBuiltInSourceTransformer(name)

Enables a built-in source transformer by name. Currently, SandboxedModule ships
with two built in source transformers:

* "coffee" - Compiles source with CoffeeScript [Enabled by default for backwards compatibility].
  Be sure to run `require('coffee-script').register()` or `require('coffee-script/register')` as well.
* "istanbul" - Instruments sources via istanbul when istanbul code coverage is running.

For example, if you'd like to use SandboxedModule in conjunction with istanbul,
just run `SandboxedModule.registerBuiltInSourceTransformer('istanbul')`.

### sandboxedModule.filename

The full path to the module.

### sandboxedModule.module

The underlaying node.js `Module` instance.

### sandboxedModule.exports

A getter returning the `sandboxedModule.module.exports` object.

### sandboxedModule.globals

The global object of the v8 context this module was loaded in. Modifications
to this object will be reflected in the sandboxed module.

### sandboxedModule.locals

The local variables injected into the sandboxed module using a closure.
Modifying this object has no effect on the state of the sandbox.

### sandboxedModule.required

An object holding a list of all module required by the sandboxed module itself.
The keys are the `moduleId`s used for the require calls.

### sandboxedModule.sourceTransformers

An object of named functions which will transform the source code required with
`SandboxedModule.require`. For example, CoffeeScript &
[istanbul](https://github.com/gotwarlost/istanbul) support is implemented with
built-in sourceTransformer functions (see `#registerBuiltInSourceTransformer`).

A source transformer receives the source (as it's been transformed thus far) and
**must** return the transformed source (whether it's changed or unchanged).

An example source transformer to change all instances of the number "3" to "5"
would look like this:

``` javascript
SandboxedModule.require('../fixture/baz', {
  sourceTransformers: {
    turn3sInto5s: function(source) {
      return source.replace(/3/g,'5');
    }
  }
})
```

## License

sandboxed-module is licensed under the MIT license.