Security News
The Dark Side of Open Source
At Node Congress, Socket CEO Feross Aboukhadijeh uncovers the darker aspects of open source, where applications that rely heavily on third-party dependencies can be exploited in supply chain attacks.
@hmcts/requestretry
Advanced tools
Readme
request-retry - HTTP(s) request retry on recoverable errors.
When the connection fails with one of ECONNRESET
, ENOTFOUND
, ESOCKETTIMEDOUT
, ETIMEDOUT
, ECONNREFUSED
, EHOSTUNREACH
, EPIPE
, EAI_AGAIN
or when an HTTP 5xx error occurrs, the request will automatically be re-attempted as these are often recoverable errors and will go away on retry.
❤️ Shameless plug
Install with npm.
npm install --save requestretry
Request-retry is a drop-in replacement for request but adds two new options maxAttempts
and retryDelay
. It also adds one property to the response (or the error object, upon a network error), attempts
. It supports callbacks or promises.
var request = require('requestretry');
request({
url: 'https://api.domain.com/v1/a/b',
json: true,
// The below parameters are specific to request-retry
maxAttempts: 5, // (default) try 5 times
retryDelay: 5000, // (default) wait for 5s before trying again
retryStrategy: request.RetryStrategies.HTTPOrNetworkError // (default) retry on 5xx or network errors
}, function(err, response, body){
// this callback will only be called when the request succeeded or after maxAttempts or on error
if (response) {
console.log('The number of request attempts: ' + response.attempts);
}
});
When you're using promises, you can pass the two following options:
fullResponse
(default true) - To resolve the promise with the full response or just the bodypromiseFactory
(default whenjs) - A function to allow the usage of a different promise implementation libraryrequest({
url: 'https://api.domain.com/v1/a/b',
json: true,
fullResponse: true // (default) To resolve the promise with the full response or just the body
})
.then(function (response) {
// response = The full response object or just the body
})
.catch(function(error) {
// error = Any occurred error
})
Using promiseFactory
option to use a different promise implementation library
// See the tests for different libraries usage examples
/**
* @param {Function} resolver The promise resolver function
* @return {Object} The promise instance
*/
function customPromiseFactory(resolver) {
// With when.js
return require('when').promise(resolver);
// With RSVP.js
var Promise = require('rsvp').Promise;
return new Promise(resolver);
}
request({
url: 'https://api.domain.com/v1/a/b',
json: true,
// Custom promise factory function
promiseFactory: customPromiseFactory
})
.then(function (response) {
// response = The full response object or just the body
})
.catch(function(error) {
// error = Any occurred error
})
A retry strategy let you specify when request-retry should retry a request
/**
* @param {Null | Object} err
* @param {Object} response
* @param {Object} body
* @return {Boolean} true if the request should be retried
*/
function myRetryStrategy(err, response, body){
// retry the request if we had an error or if the response was a 'Bad Gateway'
return err || response.statusCode === 502;
}
request({
url: 'https://api.domain.com/v1/a/b'
json:true,
retryStrategy: myRetryStrategy
}, function(err, response, body){
// this callback will only be called when the request succeeded or after maxAttempts or on error
});
A delay strategy let you specify how long request-retry should wait before trying again the request
/**
* @param {Null | Object} err
* @param {Object} response
* @param {Object} body
* @return {Number} number of milliseconds to wait before trying again the request
*/
function myDelayStrategy(err, response, body){
// set delay of retry to a random number between 500 and 3500 ms
return Math.floor(Math.random() * (3500 - 500 + 1) + 500);
}
request({
url: 'https://api.domain.com/v1/a/b'
json:true,
delayStrategy: myDelayStrategy // delayStrategy is called 1 less times than the maxAttempts set
}, function(err, response, body){
// this callback will only be called when the request succeeded or after maxAttempts or on error
});
Here is how to implement an exponential backoff strategy:
/**
* @param {Number} attempts The number of times that the request has been attempted.
* @return {Number} number of milliseconds to wait before retrying again the request.
*/
function getExponentialBackoff(attempts) {
return (Math.pow(2, attempts) * 100) + Math.floor(Math.random() * 50);
}
function constructExponentialBackoffStrategy() {
let attempts = 0;
return () => {
attempts += 1;
return getExponentialBackoff(attempts);
};
}
request({
url: 'https://api.domain.com/v1/a/b'
json:true,
delayStrategy: constructExponentialBackoffStrategy() // need to invoke the function to return the closure.
}, function(err, response, body){
// this callback will only be called when the request succeeded or after maxAttempts or on error
});
request
optionsYou can use the defaults
method to provide default options like so:
var request = require('requestretry').defaults({ json: true, retryStrategy: myRetryStrategy });
As with request
, several helpers are provided for various HTTP methods and usage:
request(options [, callback])
.request(url [, callback])
- same as request(options [, callback])
.request(url, options [, callback])
- same as request(options [, callback])
.request.get(url [, callback])
- same as request(options [, callback])
, defaults options.method
to GET
.request.get(url, options [, callback])
- same as request(options [, callback])
, defaults options.method
to GET
.request.head(url)
- same as request(options [, callback])
, defaults options.method
to HEAD
.request.post(url)
- same as request(options [, callback])
, defaults options.method
to POST
.request.put(url)
- same as request(options [, callback])
, defaults options.method
to PUT
.request.patch(url)
- same as request(options [, callback])
, defaults options.method
to PATCH
.request.del(url)
- same as request(options [, callback])
, defaults options.method
to DELETE
.request.delete(url)
- same as request(options [, callback])
, defaults options.method
to DELETE
.I maintain this project in my free time, if it helped you, well, I would be grateful to buy a beer thanks to your paypal or Bitcoins, donation!
FAQs
request-retry wrap nodejs request to retry http(s) requests in case of error
The npm package @hmcts/requestretry receives a total of 38 weekly downloads. As such, @hmcts/requestretry popularity was classified as not popular.
We found that @hmcts/requestretry demonstrated a not healthy version release cadence and project activity because the last version was released a year ago. It has 14 open source maintainers collaborating on the project.
Did you know?
Socket for GitHub automatically highlights issues in each pull request and monitors the health of all your open source dependencies. Discover the contents of your packages and block harmful activity before you install or update your dependencies.
Security News
At Node Congress, Socket CEO Feross Aboukhadijeh uncovers the darker aspects of open source, where applications that rely heavily on third-party dependencies can be exploited in supply chain attacks.
Research
Security News
The Socket Research team found this npm package includes code for collecting sensitive developer information, including your operating system username, Git username, and Git email.
Security News
OpenJS is warning of social engineering takeovers targeting open source projects after receiving a credible attempt on the foundation.