bindings

What is bindings?

The 'bindings' npm package is a utility that helps load compiled bindings for Node.js addons. It simplifies the process of including and distributing native C++ addons with Node.js modules by resolving the path to the compiled binary based on the current platform, architecture, and module version.

What are bindings's main functionalities?

Loading compiled bindings

This code demonstrates how to load a compiled Node.js addon using the 'bindings' package. The 'bindings' function is called with the name of the addon, and it returns the loaded module.

const bindings = require('bindings');
const addon = bindings('addon');

Other packages similar to bindings

node-gyp

node-gyp is a cross-platform command-line tool written in Node.js for compiling native addon modules for Node.js. It is similar to 'bindings' in that it deals with native addons, but node-gyp focuses on the build process, whereas 'bindings' focuses on loading the compiled binaries.

node-pre-gyp

node-pre-gyp is a tool that provides a way to publish and install Node.js C++ addons from binaries. It is similar to 'bindings' as it helps in managing native addon modules, but node-pre-gyp focuses on the installation of pre-compiled binaries, potentially avoiding the need for a build toolchain on the installing machine.

ffi-napi

ffi-napi is a Node.js addon for loading and calling dynamic libraries using pure JavaScript. It is similar to 'bindings' in that it allows interaction with native code, but ffi-napi uses foreign function interfaces to directly call into dynamic libraries, bypassing the need for compiled bindings.

nan

nan (Native Abstractions for Node.js) is a header file that wraps V8 and Node.js APIs, providing a set of tools for developing native addons. While 'bindings' helps in loading compiled modules, nan helps in writing the C++ code that is compatible with different versions of Node.js and V8.

README

node-bindings

Helper module for loading your native module's bindings in a cross-platform way.

This is a helper module for authors of Node.js native addon modules. In node >= 0.7.0, it is encouraged to statically precompile your native addons for your various supported platforms and architectures, rather than depend on your users to do that. This adds two new burdens on the developer that we now need to consider while writing our module:

1. You now have to compile the bindings yourself, before publishing the module.
2. You now have to figure out which version of the bindings to load at runtime.

node-bindings attempts to solve probelm #2.

This module solves the organizational problem of how to store these bindings files with a simple directory convention:

<module_root>/compiled/<node_version>/<platform>/<arch>/bindings.node

So for example, on a 32-bit Windows platform, running node v0.6.9, the bindings.node file should be placed in:

<module_root>/compiled/0.6/win32/ia32/bindings.node

On 64-bit Mac OS X, running node v0.7.1, then the bindings file should be placed in:

<module_root>/compiled/0.7/darwin/x64/bindings.node

For reference, the calculations for the various parts that makes up the require path are:

• <module_root> - The directory where package.json is found is the root.
• <platform> - process.platform
• <arch> - process.arch
• <node_version> - parseFloat(process.versions.node)

The default "compiled" directory is compiled and the default name of every "bindings" file is bindings.node. This is configurable if you'd like.

Installation

Install with npm:

$ npm install bindings

Example

require()ing the proper bindings file for the current node version, platform and architecture is as simple as:

var bindings = require('bindings')()

// Use your bindings defined in your C files
bindings.your_c_function()

You can specify the name of the bindings file if you desire:

var bindings = require('bindings')('my_bindings')

Or you can pass in an options Object for full configuration:

var bindings = require('bindings')({
    bindings: 'my_bindings'
  , compiled: 'builddir'
})

Nice Error Output

Error: Could not load the bindings file. Tried:
 -> /Users/nrajlich/node-ffi/out/Debug/ffi_bindings.node
 -> /Users/nrajlich/node-ffi/Debug/ffi_bindings.node
 -> /Users/nrajlich/node-ffi/out/Release/ffi_bindings.node
 -> /Users/nrajlich/node-ffi/Release/ffi_bindings.node
 -> /Users/nrajlich/node-ffi/compiled/0.6/darwin/x64/ffi_bindings.node
 -> /Users/nrajlich/node-ffi/build/Release/ffi_bindings.node
 -> /Users/nrajlich/node-ffi/build/default/ffi_bindings.node
    at bindings (/Users/nrajlich/node-ffi/node_modules/bindings/bindings.js:80:13)
    at Object.<anonymous> (/Users/nrajlich/node-ffi/lib/ffi.js:3:34)
    at Module._compile (module.js:441:26)
    at Object..js (module.js:459:10)
    at Module.load (module.js:348:31)
    at Function._load (module.js:308:12)
    ...

License

(The MIT License)

Copyright (c) 2012 Nathan Rajlich <[e-mail]>

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the 'Software'), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED 'AS IS', WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.