Event handling

This section covers event subscriptions for tracking action progress and state changes.

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Overview

Actions emit events throughout their lifecycle. These events can be used to update application UI and track progress.

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Event Types

Event	Payload	Description
status-change	string	Status changed
progress	StrategyProgress	Detailed progress update
completed	void	Operation completed successfully
failed	void	Operation failed
error	LombardError	Error occurred

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Subscribing to Events

import { createLombardSDK, Chain, AssetId, StakeEvent } from '@lombard.finance/sdk';
import { config } from './lib/lombard';

const sdk = createLombardSDK(config);

const stake = sdk.chain.btc.stake({
  destChain: Chain.ETHEREUM,
  assetOut: AssetId.LBTC,
});

stake.on(StakeEvent.StatusChange, (status) => {
  // status: 'idle' | 'needs_fee_authorization' | 'ready' | 'address_ready'
});

stake.on(StakeEvent.Progress, (progress) => {
  // progress.status, progress.steps, progress.confirmations
});

stake.on(StakeEvent.Completed, () => {
  // Operation completed
});

stake.on(StakeEvent.Error, (error) => {
  // error.code, error.message, error.metadata
});

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Progress Object

interface StrategyProgress<TStatus> {
  status: TStatus;
  steps: Record<string, StepStatus>;
  confirmations?: number;
  requiredConfirmations?: number;
  metadata?: Record<string, unknown>;
}

const StepStatus = {
  IDLE: 'idle',
  PENDING: 'pending',
  COMPLETE: 'complete',
  FAILED: 'failed',
};

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Unsubscribing

const handler = (status: string) => {
  // Handle status change
};

stake.on(StakeEvent.StatusChange, handler);

// Later...
stake.off(StakeEvent.StatusChange, handler);

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Event Constants

Each action type has its own event constants.

import {
  StakeEvent,
  DepositEvent,
  UnstakeEvent,
  DeployEvent,
  RedeemEvent,
  BridgeEvent,
} from '@lombard.finance/sdk';

All event types have the same shape:

const StakeEvent = {
  Progress: 'progress',
  StatusChange: 'status-change',
  Completed: 'completed',
  Failed: 'failed',
  Error: 'error',
};

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