Wait Library

The Wait library provides a convenient way to implement polling mechanisms with customizable timeouts and intervals in TypeScript.

Installation

You can install the Wait library via npm:

npm install ts-wait

Usage

import { Wait } from 'ts-wait';

// Basic usage
await new Wait<Document>(() => client.documents.getDocument(id))
        .pollingEvery(1000)
        .withTimeout(20000)
        .until(document => document.status === 'COMPLETED')

// With maximum attempts limit
await new Wait<Document>(() => client.documents.getDocument(id))
        .pollingEvery(1000)
        .withMaxAttempts(10) // Stop after 10 polling attempts
        .until(document => document.status === 'COMPLETED')

// With exponential backoff
await new Wait<Document>(() => client.documents.getDocument(id))
        .pollingEvery(1000) // Initial interval
        .withExponentialBackoff(2, 10000) // Multiply by 2 each time, max 10 seconds
        .withTimeout(60000)
        .until(document => document.status === 'COMPLETED')

// Combining features
await new Wait<Document>(() => client.documents.getDocument(id))
        .pollingEvery(500)
        .withMaxAttempts(15)
        .withExponentialBackoff(1.5) // Gradually increase with 1.5x multiplier
        .withTimeout(30000)
        .until(document => document.status === 'COMPLETED')       

API

Wait<T> A class that represents the Wait library.

Constructor new Wait(call: () => Promise<T>): Creates a new Wait instance with the provided asynchronous function.

Methods:

withTimeout(timeout: number): Wait<T>: Sets the timeout for waiting in milliseconds (default: 30000)

pollingEvery(interval: number): Wait<T>: Sets the polling interval in milliseconds (default: 1000).

withMessage(message: string): Wait<T>: Sets a custom error message.

withMaxAttempts(maxAttempts: number): Wait<T>: Sets the maximum number of polling attempts. The polling will stop when either the timeout is reached or the maximum number of attempts is exceeded, whichever comes first.

withExponentialBackoff(multiplier: number = 2, maxInterval?: number): Wait<T>: Enables exponential backoff for the polling interval. The interval will be multiplied by the specified multiplier after each attempt. Optionally, you can set a maximum interval to cap the growth.

• multiplier: The factor by which to multiply the interval (default: 2)
• maxInterval: Optional maximum interval in milliseconds to prevent unbounded growth

async until(condition: (it: T) => boolean): Promise<T>: Waits until the provided condition function returns true or the timeout/max attempts is reached. Returns the result when the condition is met.

Contributions

Contributions are welcome! Feel free to submit issues or pull requests.

License

This library is licensed under the MIT License. See the LICENSE file for details.