Promise based generic polling.
Using npm:
$ npm install generic-polling-pulse
Basic usage (async):
const { Polling } = require('generic-polling-pulse');
//Or
import { Polling } from "generic-polling-pulse"; //ES6
const poll = new Polling();
async function doSomething() {
const run = await poll.run({
waitForFn: () => 'Basic command',
delay:1000,
retry:5,
})
}
// Basic poll is waiting for truthy response from waitForFn callback.
// poll.run will return the wanted result from the waitfor function.Basic usage (then):
const { Polling } = require('generic-polling-pulse');
//Or
import { Polling } from "generic-polling-pulse"; //ES6
const poll = new Polling();
const run = poll.run({
waitForFn: () => 'Basic command',
delay:1000,
retry:5,
});
run.then((res) => {
console.log(res)
});
// Basic poll is waiting for truthy response from waitForFn callback.
// poll.run will return the wanted result from the waitfor function.Basic usage with exponential backoff:
import { Polling } from "generic-polling-pulse";
const poll = new Polling({exponential: true});
const waitFor = () => {
Waiting for answer...
}
async function doSomething() {
const run = await poll.run({
waitForFn: waitFor,
delay: 2, // Delay in ms
retry: 10,
// We have added log function if we want to debug and more info.
logFn: ({delayTime}) => console.log('delay: '+ delayTime)
})
}Advanced examples:
A. The use of custom validations:
import { Polling } from "generic-polling-pulse";
const poll = new Polling();
const waitFor = () => {
// Waiting for answer... can return 200 | 201 | 404 | 500
// first return 404
// second return 404
// third return 200;
}
// We can use custom validate callback function to validate our waitForFn response.
// We are looking for status 200;
// The param - is actuall response response from waitForFn callback.
const customValid = (param: null | number) => {
// We are looking for 200 response from waitFor callback.
if(param === 200) return 200;
}
async function doSomething() {
const result = await poll.run({
waitForFn: waitFor,
delay:100,
retry:11,
validateFn: customValid
})
}B. Usage of types
import { Polling } from "generic-polling-pulse";
const poll = new Polling();
async function doSomething() {
const result = await poll.run<{name: string, last: string}>({
waitForFn: waitFor,
delay:100,
retry:11,
// We can use custom validate callback function to validate our waitForFn response.
validateFn: (obj) => {if(obj && obj.name && obj.last) return true}
})
}C. WaitFor usage of parameters:
import { Polling } from "generic-polling-pulse";
const poll = new Polling();
const waitForWithParams = async (token: string) => {
... fetch(url) logic waits untill data recived;
return 'My name is: ' + ' ' + name + ' ' + lastName;
}
async function doSomething() {
const result = await poll.run<{name: string, last: string}>({
waitForFn: waitForWithParams,
delay:100, // delay in ms
retry:11, // Number of retries
params: ['12345678a'] // Params used for waitForFn
})
} run<T>({waitForFn, validateFn, logFn, delay, retry, params, power}): Promise<T>| CallBacks | explanation |
|---|---|
| waitForFn | WaitFor Function is the function you want to run poll on. The default validation process checks if the WaitFor has a truthy response. For custom validation please use "validateFn". |
| validateFn | Validate Function accepts waitForFunction's result. The default validation checks if the response is truthy or not. You can use this function to write your own custom logic. |
| logFn | logger accepts callback function that returns some logging information. {result, retry, delayTime}. |
| Params | -- |
| delay | Sets a delay in ms. |
| retry | Sets the number of maximum polling runs. |
| params | Sets a parameters that will be called by the waitForFn method. |
| power | Sets the power |
| retryErrorMessage | Sets custom retry error message. |
stop():{ status: string } // in case you want to stop polling manually. (abort/cancel)