dapp-core
A library that holds the core functional logic of a dapp on the Elrond Network
See Dapp template for live demo or checkout usage in the Github repo
Installation
The library can be installed via npm or yarn.
npm install @elrondnetwork/dapp-core
or
yarn add @elrondnetwork/dapp-core
If you need only the dapp-core basic logic, without the additional UI, consider using the --no-optional
flag.
This will not install the packages needed for the optional UI components.
npm install @elrondnetwork/dapp-core --no-optional
or
yarn add @elrondnetwork/dapp-core --no-optional
If you're transitioning from dapp-core 1.x to dapp-core 2.0, please read the Migration guide
Usage
dapp-core aims to abstract and simplify the process of interacting with users' wallets and with the Elrond Network, allowing developers to easily get started with a new application or integrate dapp-core into an existing application.
This library covers two main areas: User Identity and Transactions. The API for interacting with library's logic is exposed via hooks and methods that can be called for logging in the user, getting the status of the user or sending transactions.
However, to simplify usage even further, the library also comes with a default UI that already uses these hooks and methods under the hood. These UI elements can be easily customized with custom css classes.
The default UI is exposed via the UI
module.
import * as DappUI from "@elrondnetwork/dapp-core/UI";
Please be aware that this style of importing might also import unused code.
To reduce the amount of dead code, you can use named imports for each component like
import { UnlockPage } from "@elrondnetwork/dapp-core/UI/pages";
or
import { UnlockPage } from "@elrondnetwork/dapp-core/UI/pages/UnlockPage";
More on this below.
Prerequisites
There are a couple of requirements that need to be met for the application to work properly.
If you experience bugs, please make sure that you read these, before opening an issue
React
React
This library was built for applications that use React, it might not be suitable for usage with other libraries or frameworks.
DappProvider
DappProvider
You need to wrap your application with the DappProvider component, which is exported by the library, as we need to create a global Context to be able to manipulate the data.
import { DappProvider } from '@elrondnetwork/dapp-core/wrappers/DappProvider';
or
import { DappProvider } from '@elrondnetwork/dapp-core/wrappers';
- Wrap your application with this Provider.
<DappProvider
environment="devnet"
customNetworkConfig={customNetworkConfig}
>
environment
is a required key that is needed to configure the app's endpoints for a specific environment. Accepted values are testnet
, devnet
and mainnet
(also configured in EnvironmentsEnum
)
DappProvider also accepts an optional customNetworkConfig
object with a couple of keys.
This allows using different APIs and different connection providers to configure your network configuration.
All keys are optional
{
id?: string;
name?: string;
egldLabel?: string;
decimals?: string;
digits?: string;
gasPerDataByte?: string;
walletConnectDeepLink?: string;
walletConnectBridgeAddresses?: string;
walletAddress?: string;
apiAddress?: string;
explorerAddress?: string;
apiTimeout?: 4000;
}
UI Wrappers
UI Wrappers
The library exposes a couple of Components that are connected to the redux store and are used to display various elements
when something happens inside the app:
TransactionsToastList
will display new transactions in nice toasts at the bottom of the screen. This component is fully customizable.
import {TransactionsToastList} from "@elrondnetwork/dapp-core/UI/TransactionsToastList";
<App>
<TransactionsToastList
toastId?: string,
title: string,
className?: string
/>
<Content/>
</App>
SignTransactionsModals
will show a modal when a new transaction is submitted, prompting the user to verify and sign it.
Important! This is required to make transactions work, except when you use hooks to sign the transactions manually (more on this below).
import {SignTransactionsModals} from "@elrondnetwork/dapp-core/UI/SignTransactionsModals";
<App>
<SignTransactionsModals />
<Content/>
</App>
NotificationModal
Will show a modal to the user with various warnings and errors.
import {NotificationModal} from "@elrondnetwork/dapp-core/UI/NotificationModal";
<App>
<NotificationModal />
<Content/>
</App>
If you want to show custom notifications, you can use the useGetNotification
hook to get the notifications (like insufficient funds, errors etc).
User Identity
Dapp-core makes logging in and persisting user's session easy and hassle-free.
A handy component is AuthenticatedRoutesWrapper, which can be used to protect certain routes and redirect the user to login page if the user is not authenticated.
Import from dapp-core:
import { AuthenticatedRoutesWrapper } from '@elrondnetwork/dapp-core/wrappers/AuthenticatedRoutesWrapper';
or
import { AuthenticatedRoutesWrapper } from '@elrondnetwork/dapp-core/wrappers';
Use with routes:
<AuthenticatedRoutesWrapper
routes={routes}
unlockRoute="/unlock"
>
{appContent}
</AuthenticatedRoutesWrapper>
routes should be an array with objects with a signature similar to this:
{
path: "/dashboard",
title: "Dashboard",
component: Dashboard,
authenticatedRoute: true,
}
The important parts that makes this component work are the flag authenticatedRoute: true and the key path, which means that this route should be accessible only to authenticated users.
Login UI
Login UI
There are a couple of very handy React components that can be used to login the user and protect certain routes if the user is not logged in.
Under the DappUI
object mentioned above, you can find 4 buttons (one for each provider) which abstract away all the logic of loggin in the user and render the default UI. These buttons can be easily customized with a custom css class.
The exported buttons are:
- ExtensionLoginButton
- WalletConnectLoginButton
- LedgerLoginButton
- WebWalletLoginButton
example:
<ExtensionLoginButton
callbackRoute="/dashboard"
buttonClassName="extension-login"
loginButtonText="Extension login"
/>
They can also be used with children
<ExtensionLoginButton
callbackRoute="/dashboard"
buttonClassName="extension-login"
loginButtonText="Extension login"
>
<>
<icon/>
<p>Login text</p>
<>
</ExtensionLoginButton>
WalletConnectLoginButton
and LedgerLoginButton
will trigger a modal with a QR code and the ledger login UI, respectively.
These are automatically triggered by the buttons.
If, however, you want access to these containers without the buttons,
you can easily import and use them.
<WalletConnectLoginContainer
callbackRoute={callbackRoute}
loginButtonText="Login with Maiar"
title='Maiar Login',
logoutRoute='/unlock',
className='wallect-connect-login-modal',
lead='Scan the QR code using Maiar',
wrapContentInsideModal={wrapContentInsideModal}
redirectAfterLogin={redirectAfterLogin}
token={token}
onLoginRedirect={onLoginRedirect}
onClose={onClose}
isWalletConnectV2={true}
/>
<LedgerLoginContainer
callbackRoute={callbackRoute}
className='ledger-login-modal',
wrapContentInsideModal={wrapContentInsideModal}
redirectAfterLogin={redirectAfterLogin}
nativeAuth
onClose={onClose}
onLoginRedirect={onLoginRedirect}
/>
All login buttons and hooks accept a prop called redirectAfterLogin
which specifies of the user should be redirected automatically after login.
The default value for this boolean is false, since most apps listen for the "isLoggedIn" boolean and redirect programmatically.
If you need to authenticate some requests, you can provide the nativeAuth
flag to your login buttons. It comes as a boolean or as a configuration object. This token will be available in useGetLoginInfo
hook later, inside tokenLogin.nativeAuthToken
. If you need to use an interceptor for your requests, make sure to check out the implementation of AxiosInterceptorContext
. Use it like:
import { AxiosInterceptorContext } from '@elrondnetwork/dapp-core/wrappers/AxiosInterceptorContext';
<AxiosInterceptorContext.Provider>
<AxiosInterceptorContext.Interceptor
authenticatedDomanis={['https://my-api.com']}
>
<Router>
<DappProvider environment={EnvironmentsEnum.devnet}>
<>
<AxiosInterceptorContext.Listener />
{/*
// other components below
*/}
<TransactionsToastList />
<NotificationModal />
<SignTransactionsModals />
<Routes>...</Routes>
</>
</DappProvider>
</Router>
</AxiosInterceptorContext.Interceptor>
</AxiosInterceptorContext.Provider>
Another handly component is AuthenticatedRoutesWrapper, which can be used to protect certain routes and redirect the user to login page if the user is not authenticated.
Import from dapp-core:
import { AuthenticatedRoutesWrapper } from '@elrondnetwork/dapp-core/wrappers/AuthenticatedRoutesWrapper';
Use with routes:
<AuthenticatedRoutesWrapper
routes={routes}
unlockRoute={routeNames.unlock}
>
{appContent}
</AuthenticatedRoutesWrapper>
routes should be an array with objects with a signature similar to this:
{
path: "/dashboard",
title: "Dashboard",
component: Dashboard,
authenticatedRoute: true,
}
The important parts that makes this component work are the flag authenticatedRoute: true and the key path, which means that this route should be accessible only to authenticated users.
Login hooks
Login hooks
This area covers the login hooks, which expose a trigger function and the login data, ready to be rendered.
These hooks are exposed as named exports, which can be imported from dapp-core:
import { useExtensionLogin, useWalletConnectLogin, useLedgerLogin, useWebWalletLogin } from '@elrondnetwork/dapp-core/hooks';
or
import { useExtensionLogin } from '@elrondnetwork/dapp-core/hooks/login/useExtensionLogin';
import { useWalletConnectLogin } from '@elrondnetwork/dapp-core/hooks/login/useWebWalletLogin';
import { useLedgerLogin } from '@elrondnetwork/dapp-core/hooks/login/useLedgerLogin';
import { useWebWalletLogin } from '@elrondnetwork/dapp-core/hooks/login/useWebWalletLogin';
There are 4 available hooks:
- useExtensionLogin
- useWalletConnectLogin
- useLedgerLogin
- useWebWalletLogin
All hooks have the same response signature:
return type is as follows:
const [initiateLogin, genericLoginReturnType, customLoginReturnType] = useLoginHook({
callbackRoute,
logoutRoute,
onLoginRedirect,
});
- initiateLogin is a function that needs to be called for the login flow to be initiated;
- genericLoginReturnType is an object that is exactly the same for all hooks:
{
error: string,
loginFailed: boolean,
isLoading: boolean,
isLoggedIn: boolean
}
{
accounts: string[];
showAddressList: boolean;
startIndex: number;
selectedAddress: SelectedAddress | null;
onGoToPrevPage: () => void;
onGoToNextPage: () => void;
onSelectAddress: (address: SelectedAddress | null) => void;
onConfirmSelectedAddress: () => void;
}
for useLedgerLogin;
Reading User State
Reading User State
Once logged in, the user's session is persisted and can be read and deleted via a couple of handy functions.
For logging out, the library exposes a simple function called logout, which can be called to clear the user data.
the function accepts 2 arguments:
callbackUrl: string (optional)
the url to redirect the user to after logging him outonRedirect: (callbackUrl: string) => void (optional)
a function that will be called instead of redirecting the user.
This allows you to control how the redirect is done, for example, with react-router-dom, instead of window.location.href assignment.
Important this function will not be called for web wallet logout
You can opt-in for using the useIdleTimer
hook, which logs out the user after a period of inactivity (default set to 10 minutes). Optionally it accepts an onLogout
function that fulfills your dapp's specific logout business logic. Make sure to call the above logout
function inside this onLogout
callback.
You can also opt-in for using the useRegisterWebsocketListener
hook. The hooks accepts a callback which will get fired once a websocket message is received, receiving the string
argument provided by the event. Optionally you can simply listen to changes on account/transactions with the useGetWebsocketEvent
hook.
There are 2 ways of reading the user current state: hooks (to be used inside components and for reacting to changes in the data) and simple functions (for reading data outside of React components or inside handlers).
- hooks:
useGetLoginInfo, useGetAccountInfo, useGetNetworkConfig, useGetWebsocketEvent
; - functions:
getAccount, getAccountBalance, getAccountShard, getAddress, getIsLoggedIn;
Transactions
The dapp-core library exposes a straight-forward way of sending transactions and tracking their status, with a couple of handy UI components;
Sending Transactions
Sending Transactions
The API for sending transactions is a function called sendTransactions:
import { sendTransactions } from "@elrondnetwork/dapp-core";
It can be used to send a transaction with minimum information:
const { sessionId, error } = await sendTransactions({
transactions: [
{
value: '1000000000000000000',
data: 'ping',
receiver: contractAddress
},
],
callbackRoute?: string
transactionsDisplayInfo: TransactionsDisplayInfoType
minGasLimit?: number (optional, defaults to 50_000);
sessionInformation?: any (optional, defaults to null) extra sessionInformation that will be passed back to you via getSignedTransactions hook;
signWithoutSending?: boolean
completedTransactionsDelay?: number
redirectAfterSigning?: boolean
});
It returns a Promise that will be fulfilled with {error?: string; sessionId: string | null;}
sessionId
is the transaction's batch id which can be used to track a transaction's status and react to it.
Important! For the transaction to be signed, you will have to use either SignTransactionsModals
defined above, in the Prerequisites
section,
or the useSignTransactions
hook defined below. If you don't use one of these, the transactions won't be signed
Transaction Signing Flow
Transaction Signing Flow
Once a transaction has been submitted, you have to use either the SignTransactionsModals
or the useSignTransactions
hook,
for the user to be prompted in his provider (Extension, Maiar etc) to sign the transaction.
If you don't want to use the default modals that appear for the user when the signing process happens,
you have to use the useSignTransactions
hook to sign those transactions.
const {
callbackRoute,
transactions,
error,
sessionId,
onAbort,
hasTransactions,
canceledTransactionsMessage
} = useSignTransactions();
This hook will let you know if there are any transactions and you can programmatically abort the signing process.
We suggest displaying a message on the screen that confirms the transaction that needs to be signed.
You can also get the provider via
const { providerType, provider } = useGetAccountProvider();
and use that to display an appropriate message to the user.
For ledger, signing a transaction is simple if you're using the SignTransactionsModal
component.
It is fully customizable and will take care of walking the user through the signing flow.
If, however, you want to implement a different experience, you will have to use the useSignTransactionsWithLedger
hook.
it accepts the following props:
{
onCancel: () => void;
}
and returns an object with the following keys:
{
onSignTransaction: () => void;
onNext: () => void;
onPrev: () => void;
waitingForDevice: boolean;
onAbort: (e: React.MouseEvent) => void;
isLastTransaction: boolean;
currentStep: number;
signedTransactions?: Record<string, Transaction>;
currentTransaction: {
transaction: Transaction;
transactionTokenInfo: {
tokenId: string;
amount: string;
receiver: string;
type?: string;
nonce?: string;
multiTxData?: string;
};
isTokenTransaction: boolean;
tokenDecimals: number;
dataField: string;
};
}
Tracking a transaction
Tracking a transaction
The library exposes a hook called useTrackTransactionStatus;
import {useTrackTransactionStatus} from @elrondnetwork/dapp-core/hooks;
const transactionStatus = useTrackTransactionStatus({
transactionId: sessionId,
onSuccess,
onFail,
onCancelled,
});
transactionStatus has the following information about the transaction:
{
isPending,
isSuccessful,
isFailed,
isCancelled,
errorMessage,
status,
transactions
}
It's safe to pass in null
as a sessionId, so if the transaction wasn't yet sent, the hook will just return an empty object.
Tracking transactions' statuses
Tracking transactions' statuses
Dapp-core also exposes a number of handy hooks for tracking all, pending, failed, successful and timed out transactions.
Use:
useGetPendingTransactions
to get a list of all pending transactions.useGetSuccessfulTransactions
to get a list of all successful transactions.useGetFailedTransactions
to get a list of all pending transactions.
An especially useful hook called useGetActiveTransactionsStatus
will keep you updated with the status
of all transactions at a certain point in time.
it's return signature is
{
pending: boolean,
hasPendingTransactions: boolean,
timedOut: boolean,
fail: boolean,
success: boolean,
}
Transaction Toasts UI
Transaction Toasts UI
dapp-core also exposes a toast component for tracking transactions that uses the above mentioned hooks and displays toasts with transactions statuses.
The toasts list is exposed via TransactionsToastList UI component and can be used just by rendering it inside the application.
TransactionToastList
component renders also custom toasts. A custom toast can be added using the util function: addNewCustomToast
and can be removed using deleteCustomToast
When TransactionToastList
is also used for displaying custom toasts, is enough to call addNewCustomToast
to add new custom toast to the list;
<App>
<Router/>
<TransactionsToastList />
</App>
Important: This has to be inside the <DappProvider/>
children.
In case you don't want to use TransactionToastList
and just display a custom toast, then you have to import CustomToast
component
const customToast = addNewCustomToast(
{
toastId: 'toast-id',
message: '',
type: 'custom',
duration: 2000
}
);
<CustomToast
{...customToast}
onDelete: () => deleteCustomToast(toastId)
/>
Removing transactions manually
Removing transactions manually
Dapp-core takes care to change transactions' statuses and removes them when needed,
but if you need to do this manually, you can use the exposed functions for this:
removeTransactionsToSign(sessionId);
removeSignedTransaction(sessionId);
removeAllTransactionsToSign();
removeAllSignedTransactions();
Unit testing with Jest
The dapp-core library exposes bundles for both CommonJS and ESModules, however, in some enviornments, Jest might require manual mapping of the CommonJS output. To implement it, add the following snippet inside your jest config file.
moduleNameMapper: {
'@elrondnetwork/dapp-core/(.*)':
'<rootDir>/node_modules/@elrondnetwork/dapp-core/__commonjs/$1.js'
}
Dapp-core exports
Since version 2.0, dapp-core does not have a default export object.
You have to import everything from its own separate module. Below you can find all the exports.
You can either import everything from a module, or if you really want to make sure you're not importing anything
that is not used, you can import everything from its own file.
You can either go into their specific folder in the module for extra trimming, or import everything together.
for example, these 2 imports are both valid:
import { useExtensionLogin, useGetAccountInfo } from '@elrondnetwork/dapp-core/hooks';
and
import { useExtensionLogin } from '@elrondnetwork/dapp-core/hooks/login';
import { useGetAccountInfo } from '@elrondnetwork/dapp-core/hooks/account';
constants exports
import {
GAS_PRICE_MODIFIER,
GAS_PER_DATA_BYTE,
GAS_LIMIT,
GAS_PRICE,
DECIMALS,
DIGITS,
mnemonicWords,
ledgerErrorCodes,
fallbackNetworkConfigurations
} from '@elrondnetwork/dapp-core/constants';
hooks exports
Login
import {
useExtensionLogin,
useLedgerLogin,
useWalletConnectLogin,
useWebWalletLogin
} from '@elrondnetwork/dapp-core/hooks/login';
Account
import {
useGetAccount,
useGetAccountInfo,
useGetAccountProvider,
useGetLoginInfo,
useGetWebsocketSignalTimestamp
} from '@elrondnetwork/dapp-core/hooks/account';
Transactions
import {
useCheckTransactionStatus,
useGetActiveTransactionsStatus,
useGetFailedTransactions,
useGetPendingTransactions,
useGetSignedTransactions,
useGetSignTransactionsError,
useGetSuccessfulTransactions,
useGetTokenDetails,
useGetTransactionDisplayInfo,
useParseMultiEsdtTransferData,
useParseSignedTransactions,
useSignMultipleTransactions,
useSignTransactions,
useSignTransactionsWithDevice,
useSignTransactionsWithLedger,
} from '@elrondnetwork/dapp-core/hooks/transactions';
Misc
import {
useDebounce,
useGetNetworkConfig,
useGetNotification,
useUpdateEffect
} from '@elrondnetwork/dapp-core/hooks';
services exports
import {
removeTransactionsToSign,
removeSignedTransaction,
removeAllSignedTransactions,
removeAllTransactionsToSign,
isCrossShardTransaction,
sendTransactions,
signTransactions,
calcTotalFee
} from '@elrondnetwork/dapp-core/services';
utils exports
Account
import {
addressIsValid,
getAccount,
getAccountBalance,
getAccountShard,
getAddress,
getLatestNonce,
getShardOfAddress,
refreshAccount,
setNonce,
signMessage
} from '@elrondnetwork/dapp-core/utils/account';
Operations
import {
calculateFeeLimit,
formatAmount,
nominate,
getUsdValue,
} from '@elrondnetwork/dapp-core/utils/operations';
Transactions
import {
getTokenFromData,
isTokenTransfer,
parseMultiEsdtTransferData,
parseTransactionAfterSigning,
} from '@elrondnetwork/dapp-core/utils/transactions';
Validation
import {
getIdentifierType,
stringIsFloat,
stringIsInteger,
isContract,
isStringBase64,
} from '@elrondnetwork/dapp-core/utils';
Misc
import {
encodeToBase64,
decodeBase64,
logout,
getTokenFromData,
getIsLoggedIn,
isSelfESDTContract,
getAddressFromDataField,
} from '@elrondnetwork/dapp-core/utils';
Wrappers
import {
DappProvider,
AuthenticatedRoutesWrapper,
AppInitializer,
} from '@elrondnetwork/dapp-core/wrappers';
Web-specific imports
import {
useIdleTimer
} from '@elrondnetwork/dapp-core/web';
UI
import {
CopyButton,
FormatAmount,
ExplorerLink,
ExtensionLoginButton,
LedgerLoginButton,
LedgerLoginContainer,
NotificationModal,
PageState,
ProgressSteps,
SignTransactionsModals,
SignWithDeviceModal,
SignWithExtensionModal,
SignWithLedgerModal,
TransactionsToastList,
TransactionToast,
Trim,
UsdValue,
WalletConnectLoginButton,
WalletConnectLoginContainer,
} from '@elrondnetwork/dapp-core/UI';
or
import { CopyButton } from '@elrondnetwork/dapp-core/UI/CopyButton';
import { FormatAmount } from '@elrondnetwork/dapp-core/UI/FormatAmount';
import { ExplorerLink } from '@elrondnetwork/dapp-core/UI/ExplorerLink';
etc
Important: shouldRenderDefaultCss
was removed from all components.
React Native support
We are aware that there are projects out there that would like to use this library to allow users to seamlessly authenticate with Maiar.
You can use this library for its utility functions, like "formatAmount, parseAmount", mnemonic words list or its constants.
However, certain architectural decisions that we made do not work out of the box with React Native runtime (neither Metro nor Re.pack).
Due to this, you cannot yet use the DappProvider wrapping logic in a React Native application.
We have a couple of solutions in mind and are actively working on exploring ways to overcome these limitations.
Until then, you can use @elrondnetwork/erdjs libraries and @walletconnect to connect to Maiar.
There are also guide for doing this from the community
Roadmap
See the open issues for a list of proposed features (and known issues).
Contributing
Contributions are what make the open source community such an amazing place to be learn, inspire, and create. Any contributions you make are greatly appreciated.
One can contribute by creating pull requests, or by opening issues for discovered bugs or desired features.
- Fork the Project
- Create your Feature Branch (
git checkout -b feature/AmazingFeature
) - Commit your Changes (
git commit -m 'Add some AmazingFeature'
) - Push to the Branch (
git push origin feature/AmazingFeature
) - Open a Pull Request
Developers
The Elrond Team.
License
GPL-3.0-or-later