bnc-assist
Advanced tools
Takes care of onboarding your users, keeping them informed about
transaction status and comprehensive usage analytics with minimal
setup. Supports web3.js versions 0.20 and 1.0.
note: web3.js 1.0.0 beta versions 38, 39, 40, 41, 42, 43, 44, 45 have bugs when interacting with MetaMask, we recommend you avoid these versions of web3.js
☝️ A collection of Assist's UI elements.
👇 Assist's transaction notifications in action.
To integrate Assist.js into your dapp, you'll need to do 5 things:
onboardnpm i bnc-assist
yarn add bnc-assist
The library uses semantic versioning.
The current version is 0.5.1.
There are minified and non-minified versions.
Put this script at the top of your <head>
<script src="https://assist.blocknative.com/0-5-1/assist.js"></script>
<!-- OR... -->
<script src="https://assist.blocknative.com/0-5-1/assist.min.js"></script>
Full documentation of the config object is below, but the minimum required config
is as follows:
var bncAssistConfig = {
dappId: apiKey, // [String] The API key created on https://account.blocknative.com
networkId: networkId // [Integer] The network ID of the Ethereum network your dapp is deployd on.
// See below for instructions on how to setup for local blockchains.
};
var assistInstance = assist.init(bncAssistConfig);
onboardAt some point in your dapp's workflow, you'll want to ensure users are within an environment which
will allow them to make transactions, such as a browser with MetaMask, unlocked wallet, etc.
This is done by calling onboard. Some dapps might want to call onboard immediately upon any page
load. Others may wait until loading certain pages or until a certain button is clicked.
In any event, it is as simple as calling:
assistInstance.onboard()
.then(function(success) {
// User has been successfully onboarded and is ready to transact
// This means we can be sure of the follwing user properties:
// - They are using a compatible browser
// - They have a web3-enabled wallet installed
// - The wallet is connected to the config-specified networkId
// - The wallet is unlocked and contains at least `minimumBalance` in wei
// - They have connected their wallet to the dapp, congruent with EIP1102
})
.catch(function(error) {
// The user exited onboarding before completion
// Will let you know what stage of onboarding the user was up to when they exited
console.log(error.message);
})
The first three steps in the getting started flow will get your users onboarded. This step adds transaction support in order to help guide your users through a series of issues that can arise when signing transactions.
Using our decorated contracts will also enable some anonymized transaction-level metrics to give you insights into things including but not limited to:
Decorating your contracts is simple:
var myContract = new web3.eth.Contract(abi, address)
var myDecoratedContract = assistInstance.Contract(myContract)
// and then replace `myContract` with `myDecoratedContract`
// throughout your app
// ...
You can then use myDecoratedContract instead of myContract.
To speed things up, you can decorate the contract inline:
var myContract = assistInstance.Contract(new web3.eth.Contract(abi, address))
A JavaScript Object that is passed to the init function. Default values are in [square brackets] where they are set by Assist.js.
var config = {
networkId: Number, // The network id of the Ethereum network your dapp is working with (REQUIRED)
dappId: String, // The API key supplied to you by Blocknative (REQUIRED)
web3: Object, // The instantiated version of web3 that the dapp is using
mobileBlocked: Boolean, // Defines if the dapp works on mobile [false]
minimumBalance: String, // Defines the minimum balance in Wei that a user needs to have to use the dapp [0]
headlessMode: Boolean, // Turn off Assist UI, but still retain analytics collection [false]
messages: {
// See custom transaction messages section below for more details
txRequest: Function, // Transaction request has been initiated and is awaiting user approval
txSent: Function, // Transaction has been sent to the network
txPending: Function, // Transaction is pending and has been detected in the mempool
txSendFail: Function, // Transaction failed to be sent to the network
txStall: Function, // Transaction was sent but not received in the mempool after 30 secs
txFailed: Function, // Transaction failed
nsfFail: Function, // User doesn't have enough funds to complete transaction
txRepeat: Function, // Warning to user that they might be repeating a transaction
txAwaitingApproval: Function, // Warning to the user that they have a previous transaction awaiting approval
txConfirmReminder: Function, // A warning to the user that their current transaction is still awaiting approval
txConfirmed: Function // Transaction is confirmed
},
images: {
welcome: {
src: String, // Image URL for welcome onboard modal
srcset: String // Image URL(s) for welcome onboard modal
},
complete: {
src: String, // Image URL for complete onboard modal
srcset: String // Image URL(s) for complete onboard modal
}
},
style: {
darkMode: Boolean, // Set Assist UI to dark mode
notificationsPosition: String // Defines which corner transaction notifications will be positioned. Options: 'topLeft', 'topRight', 'bottomRight', 'bottomLeft'. ['bottomRight']
}
}
Custom transaction messages can be set to override the default messages Assist provides. To do this you provide callback functions for each eventCode that you want to override. The callback functions must return a String and will be called with the following object to provide context information about the transaction:
{
transaction: {
to: String, // The address the transaction is going to
gas: String, // Gas (wei)
gasPrice: String, // Gas price (wei)
hash: String, // The transaction hash
nonce: Number, // The transaction nonce
value: String // The value of the transaction (wei)
},
contract: {
// This object will be undefined if it is not a contract transaction
methodName: String, // The name of the method that was called
parameters: Array // The parameters that the method was called with
}
}
You can provide a messages object to the config to set global message overrides. Each callback can parse the context object that is passed to it and decide what to return or just return a standard message for each eventCode:
var config = {
//...
messages: {
txSent: function(data) {
return 'Your transaction has been sent to the network'
},
txConfirmed: function(data) {
if (data.contract.methodName === 'contribute') {
return 'Congratulations! You are now a contributor to the campaign'
}
}
// ....
}
}
Sometimes you want more granular control over the transaction messages and you have all the relevant information you need to create a custom transaction message at the time of calling the method. In that case you can also add custom transactions messages inline with your transaction calls which take precedent over the messages set globally in the config.
// 0.2 style send
myContract.vote(param1, param2, options, callback, {messages: {txPending: () => `Voting for ${param1} in progress`}})
// 1.0 style send
myContract.vote(param1, param2).send(options, {messages: {txPending: () => `Voting for ${param1} in progress`}})
The messages object must always be the last argument provided to the send method for it to be recognized.
The available ids for the networkId property of the config object:
1: mainnet3: ropsten testnet4: rinkeby testnetThe kovan testnet is not supported.
When you are running locally (e.g. using ganache), set networkId in the config to the network id that the local network is set to. Any number that is not 1, 3, 4 and 42 is valid and will be recognized as a local network. If using the Ganache CLI you can set the network id via the --networkId option.
All errors are called with eventCode and message properties.
{
eventCode: 'initFail',
message: 'An API key is required to run Assist'
}
The following are the possible error codes from Assist.js.
initFail - initialization of the library failed
mobileBlocked - mobile browsers are blocked from accessing this dapp
browserFail - browser is not compatible with web3.js wallets
walletFail - user does not have a web3-enabled wallet installed
walletEnableFail - user has not logged into their wallet
networkFail - user's web3 wallet is not connected to the correct network
nsfFail - user does not have enough funds in their wallet
By default, Assist will create UI elements in your application at certain times to guide users. You can disable this feature and run Assist in "headless mode" by setting headlessMode: true in the config. This still enables you to collect analytics, but won't change the underlying behaviour of your application at all.
Assist doesn't currently support mobile dapp browsers. If your dapp also doesn't support mobile browsers, setting mobileBlocked: true in the config will detect mobile user agents and show UI that will direct them to use a desktop browser instead. If your dapp does support mobile devices then Assist will be disabled and your transactions and contracts will work as normal. However if you call the onboard function when a user is on a mobile device, Assist will show a mobile not supported UI as onboarding isn't supported on mobile. So it is advised to check if a user is on a mobile device before calling onboard. Calling getState and referring to the mobileDevice property is an easy way of doing that.
By supplying an amount of wei to the minimumBalance option of the config, developers can limit access to their dapp to users who have at least this much Ether in their wallet.
Assist will detect transactions which look to be repeated. We notify users of repeat transactions when we see sequential transactions with the same to address and the same value.
init(config)config - Object: Config object to configure and setup Assist (Required)
The initialized version of the Assist library
var assistInstance = assist.init(assistConfig)
onboard()Promise
assistInstance.onboard()
.then(function(success) {
// User has been successfully onboarded and is ready to transact
})
.catch(function(error) {
// The user exited onboarding before completion
console.log(error.message) // Will let you know what stage of onboarding the user was up to when they exited
})
Contract(contractInstance)contractInstance - Object: Instantiated web3 contract object (Required)
A decorated contract to be used instead of the original instance
const myContract = new web3.eth.Contract(abi, address)
const myDecoratedContract = assistInstance.Contract(myContract)
mydecoratedContract.myMethod().call()
Transaction(txObject [, callback])txObject - Object: Transaction object (Required)
callback - Function: Optional error first style callback if you don't want to use promises
Promise or PromiEvent (web3.js 1.0)
assistInstance.Transaction(txObject)
.then(txHash => {
// Transaction has been sent to the network
})
.catch(error => {
console.log(error.message) // => 'User has insufficient funds'
})
getState()Promise
state = {
mobileDevice: Boolean, // User is on a mobile device
validBrowser: Boolean, // User is on a valid web3 browser
currentProvider: String, // Current provider being used to connect to the network
web3Wallet: Boolean, // User has a web3Wallet installed
accessToAccounts: Boolean, // Dapp has access to accounts
walletLoggedIn: Boolean, // User is logged in to wallet
walletEnabled: Boolean, // User has enabled EIP 1102 compliant wallet
accountAddress: String, // Address of the user's selected account
accountBalance: String, // User account balance
minimumBalance: String, // User has the minimum balance specified in the config
userCurrentNetworkId: Number, // Network id of the network the user is currently on
correctNetwork: Boolean, // User is on the network specified in the config
}
assistInstance.getState()
.then(function(state) {
if (state.validBrowser) {
console.log('valid browser')
}
})
npm i
yarn
npm test
yarn test
npm run build
yarn build
FAQs
Blocknative Assist js library for Dapp developers
The npm package bnc-assist receives a total of 14 weekly downloads. As such, bnc-assist popularity was classified as not popular.
We found that bnc-assist demonstrated a not healthy version release cadence and project activity because the last version was released a year ago. It has 1 open source maintainer collaborating on the project.
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