Connectors
Fuel Wallet Connectors offer a standardized interface to integrate multiple wallets with your DApps, simplifying wallet integration and ensuring smooth user interactions.
Fuel Connectors
Fuel Connectors
are a set of standardized interfaces that provide a way to interact with various wallets and services. They offer a consistent way to interact with different wallets and services, allowing developers to focus on building their applications rather than worrying about wallet integration.
To build your own wallet integration, you can create a custom connector that extends the abstract FuelConnector
class. This interface provides a set of methods and events that allow you to interact with the wallet and handle various operations such as connecting, disconnecting, signing messages, and sending transactions.
class MyWalletConnector extends FuelConnector
Properties
The FuelConnector
abstract class provides several properties that should be implemented to provide information about the connector.
name
The name
property is simply a string
on the connector that serves as an identifier and will be displayed to the end-user when selecting a connector.
name: string = 'My Wallet Connector';
external
The external
property is simply a boolean
that indicates when a connector is external or not. Connectors are considered external, or non-native, when they do not support the Fuel Network (e.g. Solana
, WalletConnect
).
metadata
The metadata
property on the connector provides additional information about the connector. This information will be displayed to the end-user when selecting a connector. The following is the structure of the metadata
object:
export type ConnectorMetadata = {
image?:
| string
| {
light: string;
dark: string;
};
install: {
action: string;
link: string;
description: string;
};
};
install
The metadata.install
property (required) is used to provide information about how to install the connector.
The install
object requires three properties:
action
(required) - astring
that will contain an action string that will be displayed to the user (e.g. "Install").link
(required) - astring
that will contain a URL that will be opened when the user clicks the action.description
(required) - astring
that will contain a description of the installation process.
install: {
action: 'Install',
description: 'Install the My Wallet Connector',
link: 'https://example.com/install',
},
image
The metadata.image
property (optional) provides an image that will be displayed to the end-user when selecting a connector. The image will be a URL to the image to be displayed (this can be an inline data URI, encoded in base64).
image: 'https://example.com/image.png',
You can even define a light
and dark
theme for the image by providing an object with the light
and dark
keys (these will take a similar URI as above).
image: {
light: 'https://example.com/light.png',
dark: 'https://example.com/dark.png',
},
Events
The FuelConnector
class provides a number of events that enable developers to listen for changes in the connector state. As part of implementing a custom connector, you can emit these events to notify the consumer dApp of changes.
accounts
The accounts
event is emitted every time a connector's accounts change. The event data is an array of string
addresses available on the network.
const accounts: Array<string> = ['0x1234567890abcdef'];
this.emit(this.events.accounts, accounts);
connectors
The connectors
event is emitted when the connectors are initialized. The event data is an array of FuelConnector
objects available on the network.
const connectors: Array<FuelConnector> = [new MyWalletConnector()];
this.emit(this.events.connectors, connectors);
currentConnector
The currentConnector
event is emitted every time the current connector changes. The event data is a FuelConnector
object that is currently connected.
const currentConnector: FuelConnector = new MyWalletConnector();
this.emit(this.events.currentConnector, currentConnector);
currentAccount
The currentAccount
event is emitted every time the current account changes. The event data is a string containing the current account address.
const currentAccount: string = '0x1234567890abcdef';
this.emit(this.events.currentAccount, currentAccount);
connection
The connection
event is emitted every time the connection status changes. The event data is a boolean
value that is true
if the connection is established and false
otherwise.
const connection: boolean = true;
this.emit(this.events.connection, connection);
networks
The networks
event is emitted every time the network changes. The event data will be a Network
object containing the current network information.
import type { Network } from 'fuels';
const network: Network = {
chainId: 1,
url: 'https://example.com/rpc',
};
this.emit(this.events.networks, network);
currentNetwork
The currentNetwork
event is emitted every time the current network changes. The event data will be a Network
object containing the current network information.
import type { Network } from 'fuels';
const currentNetwork: Network = {
chainId: 1,
url: 'https://example.com/rpc',
};
this.emit(this.events.currentNetwork, currentNetwork);
assets
The assets
event is emitted every time the assets change. The event data will be an array of Asset
objects available on the network.
import type { Asset } from 'fuels';
const assets: Array<Asset> = [
{
name: 'Ethereum',
symbol: 'ETH',
icon: 'https://cdn.fuel.network/assets/eth.svg',
networks: [
{
type: 'ethereum',
chainId: 11155111,
decimals: 18,
},
],
},
];
this.emit(this.events.assets, assets);
abis
The abis
event is emitted every time an ABI is added to a connector. The event data will be an array of FuelABI
object.
import type { Asset } from 'fuels';
const assets: Array<Asset> = [
{
name: 'Ethereum',
symbol: 'ETH',
icon: 'https://cdn.fuel.network/assets/eth.svg',
networks: [
{
type: 'ethereum',
chainId: 11155111,
decimals: 18,
},
],
},
];
this.emit(this.events.assets, assets);
Methods
The FuelConnector
abstract class provides a number of methods that can be implemented to perform various functions. Not all the methods are required to be implemented; if you choose not to implement a given method, then just don't include it in your connector.
ping
The ping
method is used to check if the connector is available and connected.
It will return a promise that resolves to true
if the connector is available and connected; otherwise, it will resolve to false
.
ping(): Promise<boolean>;
version
The version
method is used to get the current supported version of the connector. It returns a promise that resolves to an object containing the app
and network
versions.
The returned version strings can be in a range of formats:
- Caret Ranges (e.g.
^1.2.3
) - Tilde Ranges (e.g.
~1.2.3
) - Exact Versions (e.g.
1.2.3
)
version(): Promise<Version>;
isConnected
The isConnected
method informs if the connector is currently connected.
It will return a promise that resolves to true
if the connector is established and currently connected; otherwise, it will return false
.
isConnected(): Promise<boolean>;
connect
The connect
method initiates the current connectors authorization flow if a connection has not already been made.
It will return a promise that resolves to true
if the connection has been established successfully, or false
if the user has rejected it.
connect(): Promise<boolean>;
disconnect
The disconnect
method revokes the authorization of the current connector (provided by the connect
methods).
It will return a promise that resolves to true
if the disconnection is successful; otherwise, it will resolve to false
.
connect(): Promise<boolean>;
accounts
The accounts
method should return a list of all the accounts for the current connection.
It returns a promise that resolves to an array of addresses, pointing to the accounts currently available on the network.
accounts(): Promise<Array<string>>;
currentAccount
The currentAccount
method will return the default account address if it's authorized with the connection.
It will return a promise to resolve the issue to an address, or if the account is not authorized for the connection, it will return null
.
currentAccount(): Promise<string | null>;
signMessage
The signMessage
method initiates the sign message flow for the current connection.
It requires two arguments:
address
(string
)message
(string
)
Providing the message signing flow is successful, it will return the message signature (as a string
).
signMessage(address: string, message: string): Promise<string>;
sendTransaction
The signTransaction
method initiates the send transaction flow for the current connection.
It requires two arguments:
address
(string
)transaction
(TransactionRequestLike
)
It will return the transaction signature (as a string
) if it is successfully signed.
sendTransaction(address: string, transaction: TransactionRequestLike): Promise<string>;
assets
The assets
method returns a list of all the assets available for the current connection.
It will return a promise that will resolve to an array of assets (see Asset
) that are available on the network.
assets(): Promise<Array<Asset>>;
addAsset
The addAsset
method adds asset metadata to the connector.
It requires a single argument:
asset
(Asset
)
It returns a promise that resolves to true
if the asset is successfully added; otherwise, it resolves to false
.
addAsset(asset: Asset): Promise<boolean>;
addAssets
The addAssets
method adds multiple asset metadata to the connector.
It requires a single argument:
assets
(an Array ofAsset
).
Returns a promise that resolves to true
if the assets are successfully added; otherwise, resolves to false
.
addAssets(assets: Array<Asset>): Promise<boolean>;
addNetwork
The addNetwork
method starts the add network flow for the current connection.
It requires a single argument:
networkUrl
(string
)
Returns a promise that resolves to true
if the network is successfully added; otherwise, false
.
It should throw an error if the network is not available or the network already exists.
addNetwork(networkUrl: string): Promise<boolean>;
networks
The networks
method returns a list of all the networks available for the current connection.
Returns a promise that resolves to an array of available networks (see Network
).
networks(): Promise<Array<Network>>;
currentNetwork
The currentNetwork
method will return the current network that is connected.
It will return a promise that will resolve to the current network (see Network
).
currentNetwork(): Promise<Network>;
selectNetwork
The selectNetwork
method requests the user to select a network for the current connection.
It requires a single argument:
network
(Network
)
You call this method with either the providerUrl
or chainId
to select the network.
It will return a promise that resolves to true
if the network is successfully selected; otherwise, it will return false
.
It should throw an error if the network is not available or the network does not exist.
selectNetwork(network: SelectNetworkArguments): Promise<boolean>;
addABI
The addABI
method adds ABI information about a contract to the connector. This operation does not require an authorized connection.
It requires two arguments:
contractId
(string
)abi
(FuelABI
).
It will return a promise that will resolve to true
if the ABI is successfully added; otherwise false
.
addABI(contractId: string, abi: FuelABI): Promise<boolean>;
getABI
The getABI
method is used to get the ABI information that is sorted about a contract.
It requires a single argument:
contractId
(string
)
Returns a promise that resolves to the ABI information (as a FuelABI
) or null
if the data is unavailable.
getABI(contractId: string): Promise<FuelABI | null>;
hasABI
The hasABI
method checks if the ABI information is available for a contract.
It requires a single argument:
contractId
(string
)
Returns a promise that resolves to true
if the ABI information is available; otherwise false
.
hasABI(contractId: string): Promise<boolean>;
Connectors Manager
The TS SDK exports the Fuel
class, which serves as the connectors manager. This class provides the interface for interacting with the TS SDK and the broader Fuel ecosystem.
It can be instantiated as follows:
import { Fuel } from 'fuels';
const sdk = new Fuel();
/*
Awaits for initialization to mitigate potential race conditions
derived from the async nature of instantiating a connector.
*/
await sdk.init();
Note
We recommend initializing the Fuel class with the init
method to avoid any potential race conditions that may arise from the async nature of instantiating a connector.
Options
Several options can be passed to the Fuel
connector manager:
connectors
The connectors
option provides a list of connectors with which the Fuel
connector manager can interact. The manager interacts with the connectors, which in turn handle communication with the respective wallet. You can find a list of all the connectors in our FuelLabs/fuel-connectors
.
Below, we initialize the manager using the defaultConnectors
method which provides an array of all the default connectors available in the fuel-connectors
package. Supplying the devMode
flag as true
will enable the development wallet for the connectors (to install visit our wallet documentation).
import { Fuel } from 'fuels';
import { defaultConnectors } from '@fuels/connectors';
const sdk = await new Fuel({
connectors: defaultConnectors({
devMode: true,
}),
}).init();
storage
The storage
is used internally to store the current connector state. It can be overridden by passing an instance that extends the StorageAbstract
class.
import { Fuel, MemoryStorage } from 'fuels';
const sdk = await new Fuel({
storage: new MemoryStorage(),
}).init();
The default behavior will use LocalStorage
if the window
is available:
import { Fuel, LocalStorage } from 'fuels';
const sdk = await new Fuel({
storage: new LocalStorage(window.localStorage),
}).init();
targetObject
The targetObject
provides a target with which the Fuel
manager can interact. Used for registering events and can be overridden as follows:
import { Fuel } from 'fuels';
import type { TargetObject } from 'fuels';
const targetObject: TargetObject = window || document;
const sdk = await new Fuel({
targetObject,
}).init();
Methods
The Fuel
manager provides several methods to interact with the Manager:
All methods from connectors
The Fuel
manager provides all the methods available from the connected connectors. Thus, you can interact with the current connector as if you were interacting with the Fuel
manager directly.
If no current connector is available or connected, it will throw an error.
connectors
The connectors
method gets the current list of installed and connected connectors.
connectors: () => Promise<Array<FuelConnector>>;
getConnector
The getConnector
method resolves a connector by its name. This is useful for finding a specific connector with which to interact. If the connector is not found, it will return null
.
getConnector: (connector: FuelConnector | string) => FuelConnector | null;
hasConnector
The hasConnector
method will return true
under the following conditions:
- There is a current connector that is connected.
- A connector is connected within two seconds of calling the method.
hasConnector(): Promise<boolean>;
selectConnector
The selectConnector
method accepts a connector name and will return true
when it is available and connected. Otherwise, if not found or unavailable, it will return false
.
selectConnector(connectorName: string, options: FuelConnectorSelectOptions): Promise<boolean>;
currentConnector
The currentConnector
method will return the current connector that is connected or if one is available and connected, otherwise it'll return null
or undefined
.
currentConnector(): FuelConnector | null | undefined;
getWallet
The getWallet
method accepts an address (string or instance) as the first parameter and a provider or network as the second parameter. It will return an Account
instance for the given address (providing it is valid).
The provider or network will default to the current network if not provided. When a provider cannot be resolved, it will throw an INVALID_PROVIDER
error.
getWallet(
address: string | AbstractAddress,
providerOrNetwork?: Provider | Network
): Promise<Account>;
clean
The clean
method removes all the data currently stored in the storage
instance.
clean(): Promise<void>;
unsubscribe
The unsubscribe
method removes all currently registered event listeners.
unsubscribe(): void;
destroy
The destroy
method unsubscribes from all the event listeners and clears the storage.
destroy(): Promise<void>;
Learning Resources
For a deeper understanding of Fuel Connectors
and how to start using them in your projects, consider the following resources:
- Fuel Connectors Wiki - read about what a
Fuel Connector
is and how it works. - Fuel Connectors Guide - find out how to set up and use connectors.
- GitHub Repository - explore different connector implementations.