@fuel-ts/account v0.97.0 • Docs
Class: WalletManager
WalletManager is a upper package to manage multiple vaults like mnemonic and privateKeys.
- VaultTypes can be add to
WalletManager.Vaults
enabling to add custom Vault types. - Storage can be instantiate when initializing enabling custom storage types.
Extends
EventEmitter
Constructors
new WalletManager()
new WalletManager(
options
?):WalletManager
Parameters
• options?: WalletManagerOptions
Returns
Overrides
EventEmitter.constructor
Defined in
packages/account/src/wallet-manager/wallet-manager.ts:71
Properties
STORAGE_KEY
readonly
STORAGE_KEY:string
='WalletManager'
Defined in
packages/account/src/wallet-manager/wallet-manager.ts:64
storage
readonly
storage:StorageAbstract
Storage
Persistent encrypted data. The default storage works only on memory
.
Defined in
packages/account/src/wallet-manager/wallet-manager.ts:62
Vaults
static
Vaults: (typeofMnemonicVault
| typeofPrivateKeyVault
)[]
Vaults
Vaults are responsible to store secret keys and return an Wallet
instance, to interact with the network.
Each vault has access to its own state
Defined in
packages/account/src/wallet-manager/wallet-manager.ts:56
captureRejectionSymbol
readonly
static
captureRejectionSymbol: typeofcaptureRejectionSymbol
Value: Symbol.for('nodejs.rejection')
See how to write a custom rejection handler
.
Since
v13.4.0, v12.16.0
Inherited from
EventEmitter.captureRejectionSymbol
Defined in
node_modules/.pnpm/@types+node@22.5.5/node_modules/@types/node/events.d.ts:452
captureRejections
static
captureRejections:boolean
Value: boolean
Change the default captureRejections
option on all new EventEmitter
objects.
Since
v13.4.0, v12.16.0
Inherited from
EventEmitter.captureRejections
Defined in
node_modules/.pnpm/@types+node@22.5.5/node_modules/@types/node/events.d.ts:459
defaultMaxListeners
static
defaultMaxListeners:number
By default, a maximum of 10
listeners can be registered for any single event. This limit can be changed for individual EventEmitter
instances using the emitter.setMaxListeners(n)
method. To change the default for allEventEmitter
instances, the events.defaultMaxListeners
property can be used. If this value is not a positive number, a RangeError
is thrown.
Take caution when setting the events.defaultMaxListeners
because the change affects all EventEmitter
instances, including those created before the change is made. However, calling emitter.setMaxListeners(n)
still has precedence over events.defaultMaxListeners
.
This is not a hard limit. The EventEmitter
instance will allow more listeners to be added but will output a trace warning to stderr indicating that a "possible EventEmitter memory leak" has been detected. For any single EventEmitter
, the emitter.getMaxListeners()
and emitter.setMaxListeners()
methods can be used to temporarily avoid this warning:
import { EventEmitter } from 'node:events';
const emitter = new EventEmitter();
emitter.setMaxListeners(emitter.getMaxListeners() + 1);
emitter.once('event', () => {
// do stuff
emitter.setMaxListeners(Math.max(emitter.getMaxListeners() - 1, 0));
});
The --trace-warnings
command-line flag can be used to display the stack trace for such warnings.
The emitted warning can be inspected with process.on('warning')
and will have the additional emitter
, type
, and count
properties, referring to the event emitter instance, the event's name and the number of attached listeners, respectively. Its name
property is set to 'MaxListenersExceededWarning'
.
Since
v0.11.2
Inherited from
EventEmitter.defaultMaxListeners
Defined in
node_modules/.pnpm/@types+node@22.5.5/node_modules/@types/node/events.d.ts:498
errorMonitor
readonly
static
errorMonitor: typeoferrorMonitor
This symbol shall be used to install a listener for only monitoring 'error'
events. Listeners installed using this symbol are called before the regular 'error'
listeners are called.
Installing a listener using this symbol does not change the behavior once an 'error'
event is emitted. Therefore, the process will still crash if no regular 'error'
listener is installed.
Since
v13.6.0, v12.17.0
Inherited from
EventEmitter.errorMonitor
Defined in
node_modules/.pnpm/@types+node@22.5.5/node_modules/@types/node/events.d.ts:445
Accessors
isLocked
get
isLocked():boolean
Returns
boolean
Defined in
packages/account/src/wallet-manager/wallet-manager.ts:76
Methods
[captureRejectionSymbol]()?
optional
[captureRejectionSymbol]<K
>(error
,event
, ...args
):void
Type Parameters
• K
Parameters
• error: Error
• event: string
| symbol
• ...args: AnyRest
Returns
void
Inherited from
EventEmitter.[captureRejectionSymbol]
Defined in
node_modules/.pnpm/@types+node@22.5.5/node_modules/@types/node/events.d.ts:136
addAccount()
addAccount(
options
?):Promise
<WalletManagerAccount
>
Add account to a selected vault or on the first vault as default. If not vaults are adds it will return error
Parameters
• options?
• options.vaultId?: number
Returns
Promise
<WalletManagerAccount
>
Defined in
packages/account/src/wallet-manager/wallet-manager.ts:143
addListener()
addListener<
K
>(eventName
,listener
):this
Alias for emitter.on(eventName, listener)
.
Type Parameters
• K
Parameters
• eventName: string
| symbol
• listener
Returns
this
Since
v0.1.26
Inherited from
EventEmitter.addListener
Defined in
node_modules/.pnpm/@types+node@22.5.5/node_modules/@types/node/events.d.ts:597
addVault()
addVault(
vaultConfig
):Promise
<void
>
Add Vault, the vaultConfig.type
will look for the Vaults supported if didn't found it will throw.
Parameters
• vaultConfig: VaultConfig
Returns
Promise
<void
>
Defined in
packages/account/src/wallet-manager/wallet-manager.ts:170
emit()
emit<
K
>(eventName
, ...args
):boolean
Synchronously calls each of the listeners registered for the event named eventName
, in the order they were registered, passing the supplied arguments to each.
Returns true
if the event had listeners, false
otherwise.
import { EventEmitter } from 'node:events';
const myEmitter = new EventEmitter();
// First listener
myEmitter.on('event', function firstListener() {
console.log('Helloooo! first listener');
});
// Second listener
myEmitter.on('event', function secondListener(arg1, arg2) {
console.log(`event with parameters ${arg1}, ${arg2} in second listener`);
});
// Third listener
myEmitter.on('event', function thirdListener(...args) {
const parameters = args.join(', ');
console.log(`event with parameters ${parameters} in third listener`);
});
console.log(myEmitter.listeners('event'));
myEmitter.emit('event', 1, 2, 3, 4, 5);
// Prints:
// [
// [Function: firstListener],
// [Function: secondListener],
// [Function: thirdListener]
// ]
// Helloooo! first listener
// event with parameters 1, 2 in second listener
// event with parameters 1, 2, 3, 4, 5 in third listener
Type Parameters
• K
Parameters
• eventName: string
| symbol
• ...args: AnyRest
Returns
boolean
Since
v0.1.26
Inherited from
EventEmitter.emit
Defined in
node_modules/.pnpm/@types+node@22.5.5/node_modules/@types/node/events.d.ts:859
eventNames()
eventNames(): (
string
|symbol
)[]
Returns an array listing the events for which the emitter has registered listeners. The values in the array are strings or Symbol
s.
import { EventEmitter } from 'node:events';
const myEE = new EventEmitter();
myEE.on('foo', () => {});
myEE.on('bar', () => {});
const sym = Symbol('symbol');
myEE.on(sym, () => {});
console.log(myEE.eventNames());
// Prints: [ 'foo', 'bar', Symbol(symbol) ]
Returns
(string
| symbol
)[]
Since
v6.0.0
Inherited from
EventEmitter.eventNames
Defined in
node_modules/.pnpm/@types+node@22.5.5/node_modules/@types/node/events.d.ts:922
exportPrivateKey()
exportPrivateKey(
address
):string
Export specific account privateKey
Parameters
• address: string
| AbstractAddress
Returns
string
Defined in
packages/account/src/wallet-manager/wallet-manager.ts:128
exportVault()
exportVault<
T
>(vaultId
):ReturnType
<T
["serialize"
]>
Return the vault serialized object containing all the privateKeys, the format of the return depends on the Vault type.
Type Parameters
• T extends Vault
<object
>
Parameters
• vaultId: number
Returns
ReturnType
<T
["serialize"
]>
Defined in
packages/account/src/wallet-manager/wallet-manager.ts:84
getAccounts()
getAccounts():
WalletManagerAccount
[]
List all accounts on the Wallet Manager not vault information is revealed
Returns
Defined in
packages/account/src/wallet-manager/wallet-manager.ts:105
getMaxListeners()
getMaxListeners():
number
Returns the current max listener value for the EventEmitter
which is either set by emitter.setMaxListeners(n)
or defaults to defaultMaxListeners.
Returns
number
Since
v1.0.0
Inherited from
EventEmitter.getMaxListeners
Defined in
node_modules/.pnpm/@types+node@22.5.5/node_modules/@types/node/events.d.ts:774
getVaults()
getVaults():
object
[]
List all vaults on the Wallet Manager, this function not return secret's
Returns
object
[]
Defined in
packages/account/src/wallet-manager/wallet-manager.ts:94
getWallet()
getWallet(
address
):WalletUnlocked
Create a Wallet instance for the specific account
Parameters
• address: string
| AbstractAddress
Returns
Defined in
packages/account/src/wallet-manager/wallet-manager.ts:115
listenerCount()
listenerCount<
K
>(eventName
,listener
?):number
Returns the number of listeners listening for the event named eventName
. If listener
is provided, it will return how many times the listener is found in the list of the listeners of the event.
Type Parameters
• K
Parameters
• eventName: string
| symbol
The name of the event being listened for
• listener?: Function
The event handler function
Returns
number
Since
v3.2.0
Inherited from
EventEmitter.listenerCount
Defined in
node_modules/.pnpm/@types+node@22.5.5/node_modules/@types/node/events.d.ts:868
listeners()
listeners<
K
>(eventName
):Function
[]
Returns a copy of the array of listeners for the event named eventName
.
server.on('connection', (stream) => {
console.log('someone connected!');
});
console.log(util.inspect(server.listeners('connection')));
// Prints: [ [Function] ]
Type Parameters
• K
Parameters
• eventName: string
| symbol
Returns
Function
[]
Since
v0.1.26
Inherited from
EventEmitter.listeners
Defined in
node_modules/.pnpm/@types+node@22.5.5/node_modules/@types/node/events.d.ts:787
loadState()
loadState():
Promise
<void
>
Retrieve and decrypt WalletManager state from storage
Returns
Promise
<void
>
Defined in
packages/account/src/wallet-manager/wallet-manager.ts:246
lock()
lock():
void
Lock wallet. It removes passphrase from class instance, encrypt and hide all address and secrets.
Returns
void
Defined in
packages/account/src/wallet-manager/wallet-manager.ts:191
off()
off<
K
>(eventName
,listener
):this
Alias for emitter.removeListener()
.
Type Parameters
• K
Parameters
• eventName: string
| symbol
• listener
Returns
this
Since
v10.0.0
Inherited from
EventEmitter.off
Defined in
node_modules/.pnpm/@types+node@22.5.5/node_modules/@types/node/events.d.ts:747
on()
on<
K
>(eventName
,listener
):this
Adds the listener
function to the end of the listeners array for the event named eventName
. No checks are made to see if the listener
has already been added. Multiple calls passing the same combination of eventName
and listener
will result in the listener
being added, and called, multiple times.
server.on('connection', (stream) => {
console.log('someone connected!');
});
Returns a reference to the EventEmitter
, so that calls can be chained.
By default, event listeners are invoked in the order they are added. The emitter.prependListener()
method can be used as an alternative to add the event listener to the beginning of the listeners array.
import { EventEmitter } from 'node:events';
const myEE = new EventEmitter();
myEE.on('foo', () => console.log('a'));
myEE.prependListener('foo', () => console.log('b'));
myEE.emit('foo');
// Prints:
// b
// a
Type Parameters
• K
Parameters
• eventName: string
| symbol
The name of the event.
• listener
The callback function
Returns
this
Since
v0.1.101
Inherited from
EventEmitter.on
Defined in
node_modules/.pnpm/@types+node@22.5.5/node_modules/@types/node/events.d.ts:629
once()
once<
K
>(eventName
,listener
):this
Adds a one-time listener
function for the event named eventName
. The next time eventName
is triggered, this listener is removed and then invoked.
server.once('connection', (stream) => {
console.log('Ah, we have our first user!');
});
Returns a reference to the EventEmitter
, so that calls can be chained.
By default, event listeners are invoked in the order they are added. The emitter.prependOnceListener()
method can be used as an alternative to add the event listener to the beginning of the listeners array.
import { EventEmitter } from 'node:events';
const myEE = new EventEmitter();
myEE.once('foo', () => console.log('a'));
myEE.prependOnceListener('foo', () => console.log('b'));
myEE.emit('foo');
// Prints:
// b
// a
Type Parameters
• K
Parameters
• eventName: string
| symbol
The name of the event.
• listener
The callback function
Returns
this
Since
v0.3.0
Inherited from
EventEmitter.once
Defined in
node_modules/.pnpm/@types+node@22.5.5/node_modules/@types/node/events.d.ts:659
prependListener()
prependListener<
K
>(eventName
,listener
):this
Adds the listener
function to the beginning of the listeners array for the event named eventName
. No checks are made to see if the listener
has already been added. Multiple calls passing the same combination of eventName
and listener
will result in the listener
being added, and called, multiple times.
server.prependListener('connection', (stream) => {
console.log('someone connected!');
});
Returns a reference to the EventEmitter
, so that calls can be chained.
Type Parameters
• K
Parameters
• eventName: string
| symbol
The name of the event.
• listener
The callback function
Returns
this
Since
v6.0.0
Inherited from
EventEmitter.prependListener
Defined in
node_modules/.pnpm/@types+node@22.5.5/node_modules/@types/node/events.d.ts:886
prependOnceListener()
prependOnceListener<
K
>(eventName
,listener
):this
Adds a one-timelistener
function for the event named eventName
to the beginning of the listeners array. The next time eventName
is triggered, this listener is removed, and then invoked.
server.prependOnceListener('connection', (stream) => {
console.log('Ah, we have our first user!');
});
Returns a reference to the EventEmitter
, so that calls can be chained.
Type Parameters
• K
Parameters
• eventName: string
| symbol
The name of the event.
• listener
The callback function
Returns
this
Since
v6.0.0
Inherited from
EventEmitter.prependOnceListener
Defined in
node_modules/.pnpm/@types+node@22.5.5/node_modules/@types/node/events.d.ts:902
rawListeners()
rawListeners<
K
>(eventName
):Function
[]
Returns a copy of the array of listeners for the event named eventName
, including any wrappers (such as those created by .once()
).
import { EventEmitter } from 'node:events';
const emitter = new EventEmitter();
emitter.once('log', () => console.log('log once'));
// Returns a new Array with a function `onceWrapper` which has a property
// `listener` which contains the original listener bound above
const listeners = emitter.rawListeners('log');
const logFnWrapper = listeners[0];
// Logs "log once" to the console and does not unbind the `once` event
logFnWrapper.listener();
// Logs "log once" to the console and removes the listener
logFnWrapper();
emitter.on('log', () => console.log('log persistently'));
// Will return a new Array with a single function bound by `.on()` above
const newListeners = emitter.rawListeners('log');
// Logs "log persistently" twice
newListeners[0]();
emitter.emit('log');
Type Parameters
• K
Parameters
• eventName: string
| symbol
Returns
Function
[]
Since
v9.4.0
Inherited from
EventEmitter.rawListeners
Defined in
node_modules/.pnpm/@types+node@22.5.5/node_modules/@types/node/events.d.ts:818
removeAllListeners()
removeAllListeners(
eventName
?):this
Removes all listeners, or those of the specified eventName
.
It is bad practice to remove listeners added elsewhere in the code, particularly when the EventEmitter
instance was created by some other component or module (e.g. sockets or file streams).
Returns a reference to the EventEmitter
, so that calls can be chained.
Parameters
• eventName?: string
| symbol
Returns
this
Since
v0.1.26
Inherited from
EventEmitter.removeAllListeners
Defined in
node_modules/.pnpm/@types+node@22.5.5/node_modules/@types/node/events.d.ts:758
removeListener()
removeListener<
K
>(eventName
,listener
):this
Removes the specified listener
from the listener array for the event named eventName
.
const callback = (stream) => {
console.log('someone connected!');
};
server.on('connection', callback);
// ...
server.removeListener('connection', callback);
removeListener()
will remove, at most, one instance of a listener from the listener array. If any single listener has been added multiple times to the listener array for the specified eventName
, then removeListener()
must be called multiple times to remove each instance.
Once an event is emitted, all listeners attached to it at the time of emitting are called in order. This implies that any removeListener()
or removeAllListeners()
calls after emitting and before the last listener finishes execution will not remove them fromemit()
in progress. Subsequent events behave as expected.
import { EventEmitter } from 'node:events';
class MyEmitter extends EventEmitter {}
const myEmitter = new MyEmitter();
const callbackA = () => {
console.log('A');
myEmitter.removeListener('event', callbackB);
};
const callbackB = () => {
console.log('B');
};
myEmitter.on('event', callbackA);
myEmitter.on('event', callbackB);
// callbackA removes listener callbackB but it will still be called.
// Internal listener array at time of emit [callbackA, callbackB]
myEmitter.emit('event');
// Prints:
// A
// B
// callbackB is now removed.
// Internal listener array [callbackA]
myEmitter.emit('event');
// Prints:
// A
Because listeners are managed using an internal array, calling this will change the position indices of any listener registered after the listener being removed. This will not impact the order in which listeners are called, but it means that any copies of the listener array as returned by the emitter.listeners()
method will need to be recreated.
When a single function has been added as a handler multiple times for a single event (as in the example below), removeListener()
will remove the most recently added instance. In the example the once('ping')
listener is removed:
import { EventEmitter } from 'node:events';
const ee = new EventEmitter();
function pong() {
console.log('pong');
}
ee.on('ping', pong);
ee.once('ping', pong);
ee.removeListener('ping', pong);
ee.emit('ping');
ee.emit('ping');
Returns a reference to the EventEmitter
, so that calls can be chained.
Type Parameters
• K
Parameters
• eventName: string
| symbol
• listener
Returns
this
Since
v0.1.26
Inherited from
EventEmitter.removeListener
Defined in
node_modules/.pnpm/@types+node@22.5.5/node_modules/@types/node/events.d.ts:742
removeVault()
removeVault(
index
):Promise
<void
>
Remove vault by index, by remove the vault you also remove all accounts created by the vault.
Parameters
• index: number
Returns
Promise
<void
>
Defined in
packages/account/src/wallet-manager/wallet-manager.ts:161
setMaxListeners()
setMaxListeners(
n
):this
By default EventEmitter
s will print a warning if more than 10
listeners are added for a particular event. This is a useful default that helps finding memory leaks. The emitter.setMaxListeners()
method allows the limit to be modified for this specific EventEmitter
instance. The value can be set to Infinity
(or 0
) to indicate an unlimited number of listeners.
Returns a reference to the EventEmitter
, so that calls can be chained.
Parameters
• n: number
Returns
this
Since
v0.3.5
Inherited from
EventEmitter.setMaxListeners
Defined in
node_modules/.pnpm/@types+node@22.5.5/node_modules/@types/node/events.d.ts:768
unlock()
unlock(
passphrase
):Promise
<void
>
Unlock wallet. It sets passphrase on WalletManger instance load all address from configured vaults. Vaults with secrets are not unlocked or instantiated on this moment.
Parameters
• passphrase: string
Returns
Promise
<void
>
Defined in
packages/account/src/wallet-manager/wallet-manager.ts:205
updatePassphrase()
updatePassphrase(
oldpass
,newpass
):Promise
<void
>
Update WalletManager encryption passphrase
Parameters
• oldpass: string
• newpass: string
Returns
Promise
<void
>
Defined in
packages/account/src/wallet-manager/wallet-manager.ts:227
addAbortListener()
static
addAbortListener(signal
,resource
):Disposable
Experimental
Listens once to the abort
event on the provided signal
.
Listening to the abort
event on abort signals is unsafe and may lead to resource leaks since another third party with the signal can call e.stopImmediatePropagation()
. Unfortunately Node.js cannot change this since it would violate the web standard. Additionally, the original API makes it easy to forget to remove listeners.
This API allows safely using AbortSignal
s in Node.js APIs by solving these two issues by listening to the event such that stopImmediatePropagation
does not prevent the listener from running.
Returns a disposable so that it may be unsubscribed from more easily.
import { addAbortListener } from 'node:events';
function example(signal) {
let disposable;
try {
signal.addEventListener('abort', (e) => e.stopImmediatePropagation());
disposable = addAbortListener(signal, (e) => {
// Do something when signal is aborted.
});
} finally {
disposable?.[Symbol.dispose]();
}
}
Parameters
• signal: AbortSignal
• resource
Returns
Disposable
Disposable that removes the abort
listener.
Since
v20.5.0
Inherited from
EventEmitter.addAbortListener
Defined in
node_modules/.pnpm/@types+node@22.5.5/node_modules/@types/node/events.d.ts:437
getEventListeners()
static
getEventListeners(emitter
,name
):Function
[]
Returns a copy of the array of listeners for the event named eventName
.
For EventEmitter
s this behaves exactly the same as calling .listeners
on the emitter.
For EventTarget
s this is the only way to get the event listeners for the event target. This is useful for debugging and diagnostic purposes.
import { getEventListeners, EventEmitter } from 'node:events';
{
const ee = new EventEmitter();
const listener = () => console.log('Events are fun');
ee.on('foo', listener);
console.log(getEventListeners(ee, 'foo')); // [ [Function: listener] ]
}
{
const et = new EventTarget();
const listener = () => console.log('Events are fun');
et.addEventListener('foo', listener);
console.log(getEventListeners(et, 'foo')); // [ [Function: listener] ]
}
Parameters
• emitter: EventTarget
| EventEmitter
<DefaultEventMap
>
• name: string
| symbol
Returns
Function
[]
Since
v15.2.0, v14.17.0
Inherited from
EventEmitter.getEventListeners
Defined in
node_modules/.pnpm/@types+node@22.5.5/node_modules/@types/node/events.d.ts:358
getMaxListeners()
static
getMaxListeners(emitter
):number
Returns the currently set max amount of listeners.
For EventEmitter
s this behaves exactly the same as calling .getMaxListeners
on the emitter.
For EventTarget
s this is the only way to get the max event listeners for the event target. If the number of event handlers on a single EventTarget exceeds the max set, the EventTarget will print a warning.
import { getMaxListeners, setMaxListeners, EventEmitter } from 'node:events';
{
const ee = new EventEmitter();
console.log(getMaxListeners(ee)); // 10
setMaxListeners(11, ee);
console.log(getMaxListeners(ee)); // 11
}
{
const et = new EventTarget();
console.log(getMaxListeners(et)); // 10
setMaxListeners(11, et);
console.log(getMaxListeners(et)); // 11
}
Parameters
• emitter: EventTarget
| EventEmitter
<DefaultEventMap
>
Returns
number
Since
v19.9.0
Inherited from
EventEmitter.getMaxListeners
Defined in
node_modules/.pnpm/@types+node@22.5.5/node_modules/@types/node/events.d.ts:387
listenerCount()
static
listenerCount(emitter
,eventName
):number
A class method that returns the number of listeners for the given eventName
registered on the given emitter
.
import { EventEmitter, listenerCount } from 'node:events';
const myEmitter = new EventEmitter();
myEmitter.on('event', () => {});
myEmitter.on('event', () => {});
console.log(listenerCount(myEmitter, 'event'));
// Prints: 2
Parameters
• emitter: EventEmitter
<DefaultEventMap
>
The emitter to query
• eventName: string
| symbol
The event name
Returns
number
Since
v0.9.12
Deprecated
Since v3.2.0 - Use listenerCount
instead.
Inherited from
EventEmitter.listenerCount
Defined in
node_modules/.pnpm/@types+node@22.5.5/node_modules/@types/node/events.d.ts:330
on()
on(emitter, eventName, options)
static
on(emitter
,eventName
,options
?):AsyncIterableIterator
<any
[],any
,any
>
import { on, EventEmitter } from 'node:events';
import process from 'node:process';
const ee = new EventEmitter();
// Emit later on
process.nextTick(() => {
ee.emit('foo', 'bar');
ee.emit('foo', 42);
});
for await (const event of on(ee, 'foo')) {
// The execution of this inner block is synchronous and it
// processes one event at a time (even with await). Do not use
// if concurrent execution is required.
console.log(event); // prints ['bar'] [42]
}
// Unreachable here
Returns an AsyncIterator
that iterates eventName
events. It will throw if the EventEmitter
emits 'error'
. It removes all listeners when exiting the loop. The value
returned by each iteration is an array composed of the emitted event arguments.
An AbortSignal
can be used to cancel waiting on events:
import { on, EventEmitter } from 'node:events';
import process from 'node:process';
const ac = new AbortController();
(async () => {
const ee = new EventEmitter();
// Emit later on
process.nextTick(() => {
ee.emit('foo', 'bar');
ee.emit('foo', 42);
});
for await (const event of on(ee, 'foo', { signal: ac.signal })) {
// The execution of this inner block is synchronous and it
// processes one event at a time (even with await). Do not use
// if concurrent execution is required.
console.log(event); // prints ['bar'] [42]
}
// Unreachable here
})();
process.nextTick(() => ac.abort());
Use the close
option to specify an array of event names that will end the iteration:
import { on, EventEmitter } from 'node:events';
import process from 'node:process';
const ee = new EventEmitter();
// Emit later on
process.nextTick(() => {
ee.emit('foo', 'bar');
ee.emit('foo', 42);
ee.emit('close');
});
for await (const event of on(ee, 'foo', { close: ['close'] })) {
console.log(event); // prints ['bar'] [42]
}
// the loop will exit after 'close' is emitted
console.log('done'); // prints 'done'
Parameters
• emitter: EventEmitter
<DefaultEventMap
>
• eventName: string
| symbol
• options?: StaticEventEmitterIteratorOptions
Returns
AsyncIterableIterator
<any
[], any
, any
>
An AsyncIterator
that iterates eventName
events emitted by the emitter
Since
v13.6.0, v12.16.0
Inherited from
EventEmitter.on
Defined in
node_modules/.pnpm/@types+node@22.5.5/node_modules/@types/node/events.d.ts:303
on(emitter, eventName, options)
static
on(emitter
,eventName
,options
?):AsyncIterableIterator
<any
[],any
,any
>
Parameters
• emitter: EventTarget
• eventName: string
• options?: StaticEventEmitterIteratorOptions
Returns
AsyncIterableIterator
<any
[], any
, any
>
Inherited from
EventEmitter.on
Defined in
node_modules/.pnpm/@types+node@22.5.5/node_modules/@types/node/events.d.ts:308
once()
once(emitter, eventName, options)
static
once(emitter
,eventName
,options
?):Promise
<any
[]>
Creates a Promise
that is fulfilled when the EventEmitter
emits the given event or that is rejected if the EventEmitter
emits 'error'
while waiting. The Promise
will resolve with an array of all the arguments emitted to the given event.
This method is intentionally generic and works with the web platform EventTarget interface, which has no special'error'
event semantics and does not listen to the 'error'
event.
import { once, EventEmitter } from 'node:events';
import process from 'node:process';
const ee = new EventEmitter();
process.nextTick(() => {
ee.emit('myevent', 42);
});
const [value] = await once(ee, 'myevent');
console.log(value);
const err = new Error('kaboom');
process.nextTick(() => {
ee.emit('error', err);
});
try {
await once(ee, 'myevent');
} catch (err) {
console.error('error happened', err);
}
The special handling of the 'error'
event is only used when events.once()
is used to wait for another event. If events.once()
is used to wait for the 'error'
event itself, then it is treated as any other kind of event without special handling:
import { EventEmitter, once } from 'node:events';
const ee = new EventEmitter();
once(ee, 'error')
.then(([err]) => console.log('ok', err.message))
.catch((err) => console.error('error', err.message));
ee.emit('error', new Error('boom'));
// Prints: ok boom
An AbortSignal
can be used to cancel waiting for the event:
import { EventEmitter, once } from 'node:events';
const ee = new EventEmitter();
const ac = new AbortController();
async function foo(emitter, event, signal) {
try {
await once(emitter, event, { signal });
console.log('event emitted!');
} catch (error) {
if (error.name === 'AbortError') {
console.error('Waiting for the event was canceled!');
} else {
console.error('There was an error', error.message);
}
}
}
foo(ee, 'foo', ac.signal);
ac.abort(); // Abort waiting for the event
ee.emit('foo'); // Prints: Waiting for the event was canceled!
Parameters
• emitter: EventEmitter
<DefaultEventMap
>
• eventName: string
| symbol
• options?: StaticEventEmitterOptions
Returns
Promise
<any
[]>
Since
v11.13.0, v10.16.0
Inherited from
EventEmitter.once
Defined in
node_modules/.pnpm/@types+node@22.5.5/node_modules/@types/node/events.d.ts:217
once(emitter, eventName, options)
static
once(emitter
,eventName
,options
?):Promise
<any
[]>
Parameters
• emitter: EventTarget
• eventName: string
• options?: StaticEventEmitterOptions
Returns
Promise
<any
[]>
Inherited from
EventEmitter.once
Defined in
node_modules/.pnpm/@types+node@22.5.5/node_modules/@types/node/events.d.ts:222
setMaxListeners()
static
setMaxListeners(n
?, ...eventTargets
?):void
import { setMaxListeners, EventEmitter } from 'node:events';
const target = new EventTarget();
const emitter = new EventEmitter();
setMaxListeners(5, target, emitter);
Parameters
• n?: number
A non-negative number. The maximum number of listeners per EventTarget
event.
• ...eventTargets?: (EventTarget
| EventEmitter
<DefaultEventMap
>)[]
Returns
void
Since
v15.4.0
Inherited from
EventEmitter.setMaxListeners
Defined in
node_modules/.pnpm/@types+node@22.5.5/node_modules/@types/node/events.d.ts:402