A class that extends node.js events to create custom event listeners for apps relying on web3
github: https://github.com/Schwartz10/web3-event-manager
Configuration:
npm install web3-event-manager
Wherever you require web3-event-manager, create a new instance of the class:
const web3EventManager = When you want the web3EventManager to start listening for changes, run:
web3EventManager.start()
If you want the web3EventManager to stop listening for changes, run:
web3EventManager.stop()
Events to listen for:
Currently, the web3EventManager will fire callbacks, passing this data object when it hears change events. Further descriptions can be found below the table.
| Event | Data |
|---|---|
web3Change |
{ data: { hasWeb3: bool, web3: web3Obj } } |
accountChange |
{ data: { unlockedAccount: bool, account: address or null } } |
networkChange |
{ data: { currentNetworkId: num, onCorrectNetwork: bool } } |
web3Change:
web3EventManager.on('web3Change', callback)
Will fire the callback with a boolean if the user has a web3 object in their browser. The web3 object is accessible via the data object. To stop listening, call:
web3EventManager.removeListener('web3Change', callback)
accountChange:
web3EventManager.on('accountChange', callback)
Will fire the callback with a boolean if the user has an unlocked ethereum account. The unlocked account's address is also provided in the data object. To stop listening, call:
web3EventManager.removeListener('accountChange', callback)
networkChange:
web3EventManager.on('networkChange', callback)
Will fire the callback with a number representing the networkId of the network protocol the web3 object corresponds to. If the Web3EventManager was constructed with a required network (see Web3EventManager arguments), the data returned will provide a boolean if the user is on the required network (and true if no required network was provided). To stop listening, call:
web3EventManager.removeListener('networkChange', callback)
Instantiating the Web3Manager with arguments:
The Web3Manager currently takes 3 optional arguments:
(1) interval (number) - instructs the Web3Manager to check for updates every (number) of milliseconds
(2) requiredNetwork (number) - tells the Web3Manager that the user must be connected to a requiredNetwork
(3) localProvider (string (localhost...)) - instructs the Web3Manager to construct the web3 object out of the localProvider, instead of the current provider injected into the browser by metamask, mist, or other related services.
If you wish to use these, simply call:
const Web3EventManager = new Web3Manager(interval, requiredNetwork, localProvider)