LogsSubscription

LogSubscription to be used to subscribe to events logs.

Following events are supported and can be accessed with either LogsSubscription.once or $LogsSubscription.on methods.

• connected: Emitted when the subscription is connected.
• data: Fires on each incoming event with the event object as argument.
• changed: Fires on each event which was removed from the blockchain. The event will have the additional property removed: true.
• error: Fires on each error.

const subscription = await myContract.events.MyEvent({
  filter: {myIndexedParam: [20,23], myOtherIndexedParam: '0x123456789...'}, // Using an array means OR: e.g. 20 or 23
  fromBlock: 0
});

subscription.on("connected", function(subscriptionId){
  console.log(subscriptionId);
});

subscription.on('data', function(event){
  console.log(event); // same results as the optional callback above
});

subscription.on('changed', function(event){
  // remove event from local database
})

subscription.on('error', function(error, receipt) { // If the transaction was rejected by the network with a receipt, the second parameter will be the receipt.
  ...
});

// event output example
> {
  returnValues: {
      myIndexedParam: 20,
      myOtherIndexedParam: '0x123456789...',
      myNonIndexParam: 'My String'
  },
  raw: {
      data: '0x7f9fade1c0d57a7af66ab4ead79fade1c0d57a7af66ab4ead7c2c2eb7b11a91385',
      topics: ['0xfd43ade1c09fade1c0d57a7af66ab4ead7c2c2eb7b11a91ffdd57a7af66ab4ead7', '0x7f9fade1c0d57a7af66ab4ead79fade1c0d57a7af66ab4ead7c2c2eb7b11a91385']
  },
  event: 'MyEvent',
  signature: '0xfd43ade1c09fade1c0d57a7af66ab4ead7c2c2eb7b11a91ffdd57a7af66ab4ead7',
  logIndex: 0,
  transactionIndex: 0,
  transactionHash: '0x7f9fade1c0d57a7af66ab4ead79fade1c0d57a7af66ab4ead7c2c2eb7b11a91385',
  blockHash: '0xfd43ade1c09fade1c0d57a7af66ab4ead7c2c2eb7b11a91ffdd57a7af66ab4ead7',
  blockNumber: 1234,
  address: '0xde0B295669a9FD93d5F28D9Ec85E40f4cb697BAe'
}

Hierarchy

• Web3Subscription<{ changed: EventLog & { removed: true }; data: EventLog }, { abi: AbiEventFragment; address?: HexString; topics?: (Topic | Topic[] | null)[] }>
  • LogsSubscription

Index

Constructors

• constructor

Properties

• abi
• address
• args
• jsonInterface
• topics

Accessors

• id
• lastBlock

Methods

• _processSubscriptionError
• _processSubscriptionResult
• emit
• eventNames
• getMaxListeners
• listenerCount
• listeners
• off
• on
• once
• processSubscriptionData
• removeAllListeners
• resubscribe
• sendSubscriptionRequest
• sendUnsubscribeRequest
• setMaxListenerWarningThreshold
• subscribe
• unsubscribe

Constructors

publicconstructor

• new LogsSubscription(args: { abi: AbiBaseFragment & { anonymous?: boolean; inputs?: readonly AbiParameter[]; name: string; type: string } & { signature: string }; address?: string; jsonInterface: ContractAbiWithSignature; topics?: (null | string | string[])[] }, options: { returnFormat?: DataFormat; subscriptionManager: Web3SubscriptionManager<unknown, {}> }): LogsSubscription
• new LogsSubscription(args: { abi: AbiBaseFragment & { anonymous?: boolean; inputs?: readonly AbiParameter[]; name: string; type: string } & { signature: string }; address?: string; jsonInterface: ContractAbiWithSignature; topics?: (null | string | string[])[] }, options: { requestManager: Web3RequestManager<EthExecutionAPI>; returnFormat?: DataFormat }): LogsSubscription

• Overrides Web3Subscription.constructor

  Parameters

  • args: { abi: AbiBaseFragment & { anonymous?: boolean; inputs?: readonly AbiParameter[]; name: string; type: string } & { signature: string }; address?: string; jsonInterface: ContractAbiWithSignature; topics?: (null | string | string[])[] }

  • options: { returnFormat?: DataFormat; subscriptionManager: Web3SubscriptionManager<unknown, {}> }

  Returns LogsSubscription

Properties

publicreadonlyabi

abi: AbiBaseFragment & { anonymous?: boolean; inputs?: readonly AbiParameter[]; name: string; type: string } & { signature: string }

The JSON Interface of the event.

publicoptionalreadonlyaddress

address?: string

Address of tye contract

readonlyargs

args: { abi: AbiEventFragment; address?: string; topics?: (null | string | string[])[] }

Inherited from Web3Subscription.args

Type declaration

• abi: AbiEventFragment

• optionaladdress?: string

• optionaltopics?: (null | string | string[])[]

publicreadonlyjsonInterface

jsonInterface: ContractAbiWithSignature

publicoptionalreadonlytopics

topics?: (null | string | string[])[]

The list of topics subscribed

Accessors

id

• get id(): undefined | string

• Inherited from Web3Subscription.id

  Returns undefined | string

lastBlock

• get lastBlock(): undefined | BlockOutput

• Inherited from Web3Subscription.lastBlock

  Returns undefined | BlockOutput

Methods

_processSubscriptionError

• _processSubscriptionError(error: Error): void

• Inherited from Web3Subscription._processSubscriptionError

  Parameters

  • error: Error

  Returns void

_processSubscriptionResult

• _processSubscriptionResult(data: unknown): void

• Inherited from Web3Subscription._processSubscriptionResult

  Parameters

  • data: unknown

  Returns void

emit

• emit<K>(eventName: K, params: { changed: EventLog & { removed: true }; data: EventLog } & CommonSubscriptionEvents[K]): void

• Inherited from Web3Subscription.emit

  Type parameters

  • K: Web3EventKey<{ changed: EventLog & { removed: true }; data: EventLog } & CommonSubscriptionEvents>

  Parameters

  • eventName: K

  • params: { changed: EventLog & { removed: true }; data: EventLog } & CommonSubscriptionEvents[K]

  Returns void

eventNames

• eventNames(): (string | symbol)[]

• Inherited from Web3Subscription.eventNames

  Returns (string | symbol)[]

getMaxListeners

• getMaxListeners(): number

• Inherited from Web3Subscription.getMaxListeners

  Returns number

listenerCount

• listenerCount<K>(eventName: K): number

• Inherited from Web3Subscription.listenerCount

  Type parameters

  • K: Web3EventKey<{ changed: EventLog & { removed: true }; data: EventLog } & CommonSubscriptionEvents>

  Parameters

  • eventName: K

  Returns number

listeners

• listeners<K>(eventName: K): (...args: any[]) => void[]

• Inherited from Web3Subscription.listeners

  Type parameters

  • K: Web3EventKey<{ changed: EventLog & { removed: true }; data: EventLog } & CommonSubscriptionEvents>

  Parameters

  • eventName: K

  Returns (...args: any[]) => void[]

off

• off<K>(eventName: K, fn: Web3EventCallback<{ changed: EventLog & { removed: true }; data: EventLog } & CommonSubscriptionEvents[K]>): void

• Inherited from Web3Subscription.off

  Type parameters

  • K: Web3EventKey<{ changed: EventLog & { removed: true }; data: EventLog } & CommonSubscriptionEvents>

  Parameters

  • eventName: K

  • fn: Web3EventCallback<{ changed: EventLog & { removed: true }; data: EventLog } & CommonSubscriptionEvents[K]>

  Returns void

on

• on<K>(eventName: K, fn: Web3EventCallback<{ changed: EventLog & { removed: true }; data: EventLog } & CommonSubscriptionEvents[K]>): void

• Inherited from Web3Subscription.on

  Type parameters

  • K: Web3EventKey<{ changed: EventLog & { removed: true }; data: EventLog } & CommonSubscriptionEvents>

  Parameters

  • eventName: K

  • fn: Web3EventCallback<{ changed: EventLog & { removed: true }; data: EventLog } & CommonSubscriptionEvents[K]>

  Returns void

once

• once<K>(eventName: K, fn: Web3EventCallback<{ changed: EventLog & { removed: true }; data: EventLog } & CommonSubscriptionEvents[K]>): void

• Inherited from Web3Subscription.once

  Type parameters

  • K: Web3EventKey<{ changed: EventLog & { removed: true }; data: EventLog } & CommonSubscriptionEvents>

  Parameters

  • eventName: K

  • fn: Web3EventCallback<{ changed: EventLog & { removed: true }; data: EventLog } & CommonSubscriptionEvents[K]>

  Returns void

processSubscriptionData

• processSubscriptionData(data: JsonRpcSubscriptionResult | JsonRpcSubscriptionResultOld<Log> | JsonRpcNotification<Log>): void

• Inherited from Web3Subscription.processSubscriptionData

  Parameters

  • data: JsonRpcSubscriptionResult | JsonRpcSubscriptionResultOld<Log> | JsonRpcNotification<Log>

  Returns void

removeAllListeners

• removeAllListeners(): EventEmitter

• Inherited from Web3Subscription.removeAllListeners

  Returns EventEmitter

resubscribe

• resubscribe(): Promise<void>

• Inherited from Web3Subscription.resubscribe

  Returns Promise<void>

sendSubscriptionRequest

• sendSubscriptionRequest(): Promise<string>

• Inherited from Web3Subscription.sendSubscriptionRequest

  Returns Promise<string>

sendUnsubscribeRequest

• sendUnsubscribeRequest(): Promise<void>

• Inherited from Web3Subscription.sendUnsubscribeRequest

  Returns Promise<void>

setMaxListenerWarningThreshold

• setMaxListenerWarningThreshold(maxListenersWarningThreshold: number): void

• Inherited from Web3Subscription.setMaxListenerWarningThreshold

  Parameters

  • maxListenersWarningThreshold: number

  Returns void

subscribe

• subscribe(): Promise<string>

• Inherited from Web3Subscription.subscribe

  Returns Promise<string>

unsubscribe

• unsubscribe(): Promise<void>

• Inherited from Web3Subscription.unsubscribe

  Returns Promise<void>