web3.setProvider(myProvider)
web3.eth.setProvider(myProvider)
web3.shh.setProvider(myProvider)
web3.bzz.setProvider(myProvider)
...Will change the provider for its module.
Note
When called on the umbrella package web3 it will also set the provider for all sub modules web3.eth, web3.shh, etc EXCEPT web3.bzz which needs a separate provider at all times.
Object-myProvider: :ref:`a valid provider <web3-providers>`.
Boolean
var Web3 = require('web3');
var web3 = new Web3('http://localhost:8545');
// or
var web3 = new Web3(new Web3.providers.HttpProvider('http://localhost:8545'));
// change provider
web3.setProvider('ws://localhost:8546');
// or
web3.setProvider(new Web3.providers.WebsocketProvider('ws://localhost:8546'));
// Using the IPC provider in node.js
var net = require('net');
var web3 = new Web3('/Users/myuser/Library/Ethereum/geth.ipc', net); // mac os path
// or
var web3 = new Web3(new Web3.providers.IpcProvider('/Users/myuser/Library/Ethereum/geth.ipc', net)); // mac os path
// on windows the path is: "\\\\.\\pipe\\geth.ipc"
// on linux the path is: "/users/myuser/.ethereum/geth.ipc"web3.providers
web3.eth.providers
web3.shh.providers
web3.bzz.providers
...Contains the current available :ref:`providers <web3-providers>`.
Object with the following providers:
Object-HttpProvider: The HTTP provider is deprecated, as it won't work for subscriptions.Object-WebsocketProvider: The Websocket provider is the standard for usage in legacy browsers.Object-IpcProvider: The IPC provider is used node.js dapps when running a local node. Gives the most secure connection.
var Web3 = require('web3');
// use the given Provider, e.g in Mist, or instantiate a new websocket provider
var web3 = new Web3(Web3.givenProvider || 'ws://remotenode.com:8546');
// or
var web3 = new Web3(Web3.givenProvider || new Web3.providers.WebsocketProvider('ws://remotenode.com:8546'));
// Using the IPC provider in node.js
var net = require('net');
var web3 = new Web3('/Users/myuser/Library/Ethereum/geth.ipc', net); // mac os path
// or
var web3 = new Web3(new Web3.providers.IpcProvider('/Users/myuser/Library/Ethereum/geth.ipc', net)); // mac os path
// on windows the path is: "\\\\.\\pipe\\geth.ipc"
// on linux the path is: "/users/myuser/.ethereum/geth.ipc"// ====
// Http
// ====
var Web3HttpProvider = require('web3-providers-http');
var options = {
keepAlive: true,
withCredentials: false,
timeout: 20000, // ms
headers: [
{
name: 'Access-Control-Allow-Origin',
value: '*'
},
{
...
}
],
agent: {
http: http.Agent(...),
baseUrl: ''
}
};
var provider = new Web3HttpProvider('http://localhost:8545', options);
// ==========
// Websockets
// ==========
var Web3WsProvider = require('web3-providers-ws');
var options = {
timeout: 30000, // ms
// Useful for credentialed urls, e.g: ws://username:password@localhost:8546
headers: {
authorization: 'Basic username:password'
},
// Useful if requests result are large
clientConfig: {
maxReceivedFrameSize: 100000000, // bytes - default: 1MiB
maxReceivedMessageSize: 100000000, // bytes - default: 8MiB
},
// Enable auto reconnection
reconnect: {
auto: true,
delay: 5000, // ms
maxAttempts: 5,
onTimeout: false
}
};
var ws = new Web3WsProvider('ws://localhost:8546', options);More information for the Http and Websocket provider modules can be found here:
web3.givenProvider
web3.eth.givenProvider
web3.shh.givenProvider
web3.bzz.givenProvider
...When using web3.js in an Ethereum compatible browser, it will set with the current native provider by that browser.
Will return the given provider by the (browser) environment, otherwise null.
Object: The given provider set or null;
web3.currentProvider
web3.eth.currentProvider
web3.shh.currentProvider
web3.bzz.currentProvider
...Will return the current provider, otherwise null.
Object: The current provider set or null;
new web3.BatchRequest()
new web3.eth.BatchRequest()
new web3.shh.BatchRequest()
new web3.bzz.BatchRequest()Class to create and execute batch requests.
none
Object: With the following methods:
add(request): To add a request object to the batch call.execute(): Will execute the batch request.
var contract = new web3.eth.Contract(abi, address);
var batch = new web3.BatchRequest();
batch.add(web3.eth.getBalance.request('0x0000000000000000000000000000000000000000', 'latest', callback));
batch.add(contract.methods.balance(address).call.request({from: '0x0000000000000000000000000000000000000000'}, callback2));
batch.execute();web3.extend(methods)
web3.eth.extend(methods)
web3.shh.extend(methods)
web3.bzz.extend(methods)
...Allows extending the web3 modules.
Note
You also have *.extend.formatters as additional formatter functions to be used for in and output formatting. Please see the source file for function details.
methods-Object: Extension object with array of methods description objects as follows:property-String: (optional) The name of the property to add to the module. If no property is set it will be added to the module directly.methods-Array: The array of method descriptions:name-String: Name of the method to add.call-String: The RPC method name.params-Number: (optional) The number of parameters for that function. Default 0.inputFormatter-Array: (optional) Array of inputformatter functions. Each array item responds to a function parameter, so if you want some parameters not to be formatted, add anullinstead.outputFormatter - ``Function: (optional) Can be used to format the output of the method.
Object: The extended module.
web3.extend({
property: 'myModule',
methods: [{
name: 'getBalance',
call: 'eth_getBalance',
params: 2,
inputFormatter: [web3.extend.formatters.inputAddressFormatter, web3.extend.formatters.inputDefaultBlockNumberFormatter],
outputFormatter: web3.utils.hexToNumberString
},{
name: 'getGasPriceSuperFunction',
call: 'eth_gasPriceSuper',
params: 2,
inputFormatter: [null, web3.utils.numberToHex]
}]
});
web3.extend({
methods: [{
name: 'directCall',
call: 'eth_callForFun',
}]
});
console.log(web3);
> Web3 {
myModule: {
getBalance: function(){},
getGasPriceSuperFunction: function(){}
},
directCall: function(){},
eth: Eth {...},
bzz: Bzz {...},
...
}