PREVIEW RELEASE This is a beta preview release with breaking changes! The current stable version is 0.20.0
web3.js - Ethereum JavaScript API
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This is the Ethereum JavaScript API
which connects to the Generic JSON RPC spec.
You need to run a local or remote Ethereum node to use this library.
Please read the documentation for more.
Installation
Node
npm install web3
Yarn
yarn add web3
Meteor
Note: works only in the Browser for now. (PR welcome).
meteor add ethereum:web3
In the Browser
Use the prebuild dist/web3.min.js
, or
build using the web3.js repository:
npm run-script build
Then include dist/web3.js
in your html file.
This will expose Web3
on the window object.
Usage
var Web3 = require('web3');
var web3 = new Web3('ws://localhost:8546');
console.log(web3);
> {
eth: ... ,
shh: ... ,
utils: ...,
...
}
Additionally you can set a provider using web3.setProvider()
(e.g. WebsocketProvider)
web3.setProvider('ws://localhost:8546');
web3.setProvider(new Web3.providers.WebsocketProvider('ws://localhost:8546'));
There you go, now you can use it:
web3.eth.getAccounts()
.then(console.log);
Documentation
Documentation can be found at read the docs
Building
Requirements
sudo apt-get update
sudo apt-get install nodejs
sudo apt-get install npm
Building (gulp)
Build only the web3.js package
npm run-script build
Or build all sub packages as well
npm run-script build-all
This will put all the browser build files into the dist
folder.
Testing (mocha)
npm test
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