Retry

The retry function is a utility method for executing promise functions with a retry mechanism.

Documents in Other Language

中文文档

Key Features

Promise: The retry function returns a Promise object that can be used to handle the final result or errors using the .then() and .catch() methods.
Asynchronous Task: An asynchronous operation performed by the function passed to promiseFn.
Retry Mechanism: In case of failure, the retry function automatically retries the task according to the specified retry count and interval to increase the chances of success.

Usage

retry(promiseFn, retryCount, retryIntervalSeconds, errorCallback);

Parameters

promiseFn: A callable Promise function that will be executed repeatedly until the maximum retry count is reached or it succeeds.
retryCount: The maximum number of retries allowed.
retryIntervalSeconds: The time interval in seconds between each retry.
errorCallback (optional): A callback function called when the last retry fails. It receives an error object as a parameter and allows you to perform custom error handling logic. If not provided, the promise will be rejected with the original error.

Installation

npm install @damo/retry

Example

const retry = require("@damo/retry");

// Define an asynchronous task
function simulateAsyncTask() {
  return new Promise((resolve, reject) => {
    const isSuccess = Math.random() < 0.5; // 50% success rate

    if (isSuccess) {
      resolve("Operation successful!");
    } else {
      reject(new Error("Operation failed!"));
    }
  });
}

// Usage example
const maxRetryCount = 3;
const retryIntervalSeconds = 2;

retry(simulateAsyncTask, maxRetryCount, retryIntervalSeconds, (error) => {
  console.error("Retry failed:", error.message);
  return "Custom error handling result";
})
  .then((result) => {
    console.log("Final result:", result);
  })
  .catch((error) => {
    console.error("Retry failed:", error.message);
  });

In the above example, we've added an errorCallback parameter as the fourth argument and handled it accordingly. When the last retry fails, the callback function is called with the error information as a parameter. You can handle custom error logic within the callback function and return the desired result.

Replace simulateAsyncTask with your actual asynchronous task function and adjust the values of maxRetryCount, retryIntervalSeconds, and errorCallback according to your requirements.

wyyxdgm / retry