Awesome
<h1 align="center"> <a href="https://elbywan.github.io/wretch"><img src="https://cdn.rawgit.com/elbywan/wretch/08831345/wretch.svg" alt="wretch-logo" width="220px"></a><br> <br> <a href="https://elbywan.github.io/wretch">Wretch middlewares</a><br> <br> <a href="https://elbywan.github.io/wretch"><img alt="homepage-badge" src="https://img.shields.io/website-up-down-green-red/http/shields.io.svg?label=wretch-homepage"></a> <a href="https://www.npmjs.com/package/wretch-middlewares"><img alt="npm-badge" src="https://img.shields.io/npm/v/wretch-middlewares.svg?colorB=ff733e" height="20"></a> <a href="https://github.com/elbywan/wretch-middlewares/blob/master/LICENSE"><img src="https://img.shields.io/badge/license-MIT-blue.svg" alt="license-badge" height="20"></a> </h1> <h4 align="center"> A collection of <a href="https://github.com/elbywan/wretch#middlewares" target="_blank">middlewares</a> for the <a href="https://github.com/elbywan/wretch" target="_blank">Wretch</a> library. </h4>Deprecation Notice
:warning: This repository is now deprecated, middlewares have been integrated into the main wretch
package starting from wretch v2.0.0
Installation
Prerequisite: install Wretch
Npm
npm i wretch-middlewares
Cdn
<!-- Global variable name : window.wretchMiddlewares -->
<script src="https://unpkg.com/wretch-middlewares"></script>
Middlewares
Dedupe | Retry | Throttling cache | Delay |
---|
Dedupe
Prevents having multiple identical requests on the fly at the same time.
Options
- skip :
(url, opts) => boolean
If skip returns true, then the dedupe check is skipped.
- key :
(url, opts) => string
Returns a key that is used to identify the request.
- resolver :
(response: Response) => Response
This function is called when resolving the fetch response from duplicate calls. By default it clones the response to allow reading the body from multiple sources.
Usage
import wretch from 'wretch'
import { dedupe } from 'wretch-middlewares'
wretch().middlewares([
dedupe({
/* Options - defaults below */
skip: (url, opts) => opts.skipDedupe || opts.method !== 'GET',
key: (url, opts) => opts.method + '@' + url,
resolver: response => response.clone()
})
])./* ... */
Retry
Retries a request multiple times in case of an error (or until a custom condition is true).
Options
- delayTimer :
milliseconds
The timer between each attempt.
- delayRamp :
(delay, nbOfAttempts) => milliseconds
The custom function that is used to calculate the actual delay based on the the timer & the number of attemps.
- maxAttempts :
number
The maximum number of retries before resolving the promise with the last error. Specifying 0 means infinite retries.
- until :
(fetchResponse, error) => boolean | Promise<boolean>
The request will be retried until that condition is satisfied.
- onRetry :
({ response, error, url, options }) => { url?, options? } || Promise<{url?, options?}>
Callback that will get executed before retrying the request. If this function returns an object having url and/or options properties, they will override existing values in the retried request. If it returns a Promise, it will be awaited before retrying the request.
- retryOnNetworkError :
boolean
If true, will retry the request if a network error was thrown. Will also provide an 'error' argument to the onRetry
and until
methods.
- resolver :
(response: Response) => Response
This function is called when resolving the fetch response from duplicate calls. By default it clones the response to allow reading the body from multiple sources.
Usage
import wretch from 'wretch'
import { retry } from 'wretch-middlewares'
wretch().middlewares([
retry({
/* Options - defaults below */
delayTimer: 500,
delayRamp: (delay, nbOfAttempts) => delay * nbOfAttempts,
maxAttempts: 10,
until: (response, error) => response && response.ok,
onRetry: null,
retryOnNetworkError: false,
resolver: response => response.clone()
})
])./* ... */
// You can also return a Promise, which is useful if you want to inspect the body:
wretch().middlewares([
retry({
until: response =>
response.json().then(body =>
body.field === 'something'
)
})
])
Throttling cache
A throttling cache which stores and serves server responses for a certain amount of time.
Options
- throttle :
milliseconds
The response will be stored for this amount of time before being deleted from the cache.
- skip :
(url, opts) => boolean
If skip returns true, then the dedupe check is skipped.
- key :
(url, opts) => string
Returns a key that is used to identify the request.
- clear
(url, opts) => boolean
Clears the cache if true.
- invalidate
(url, opts) => string | RegExp | Array<string | RegExp> | null
Removes url(s) matching the string or RegExp from the cache. Can use an array to invalidate multiple values.
- condition
response => boolean
If false then the response will not be added to the cache.
- flagResponseOnCacheHit
string
If set, a Response returned from the cache whill be flagged with a property name equal to this option.
Usage
import wretch from 'wretch'
import { throttlingCache } from 'wretch-middlewares'
wretch().middlewares([
throttlingCache({
/* Options - defaults below */
throttle: 1000,
skip: (url, opts) => opts.skipCache || opts.method !== 'GET',
key: (url, opts) => opts.method + '@' + url,
clear: (url, opts) => false,
invalidate: (url, opts) => null,
condition: response => response.ok,
flagResponseOnCacheHit: '__cached'
})
])./* ... */
Delay
Delays the request by a specific amount of time.
Options
- time :
milliseconds
The request will be delayed by that amount of time.
Usage
import wretch from 'wretch'
import { delay } from 'wretch-middlewares'
wretch().middlewares([
delay(1000)
])./* ... */