https://github.com/gcanti/retry-ts

Retry combinators for monadic actions that may fail
https://github.com/gcanti/retry-ts

fp-ts functional-programming typescript

Last synced: 20 days ago
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Retry combinators for monadic actions that may fail

• Host: GitHub
• URL: https://github.com/gcanti/retry-ts
• Owner: gcanti
• License: mit
• Created: 2018-07-02T09:48:01.000Z (over 6 years ago)
• Default Branch: master
• Last Pushed: 2022-04-05T08:14:04.000Z (over 2 years ago)
• Last Synced: 2024-10-12T22:55:30.034Z (2 months ago)
• Topics: fp-ts, functional-programming, typescript
• Language: TypeScript
• Homepage: https://gcanti.github.io/retry-ts/
• Size: 354 KB
• Stars: 168
• Watchers: 8
• Forks: 8
• Open Issues: 1
• Metadata Files:
  • Readme: README.md
  • Changelog: CHANGELOG.md
  • License: LICENSE

Awesome Lists containing this project

• awesome-ccamel - gcanti/retry-ts - Retry combinators for monadic actions that may fail (TypeScript)
• awesome-fp-ts - gcanti/retry-ts - Retry combinators for monadic actions that may fail (Domain modeling in TypeScript by Benoit Ruiz)

README

        
TypeScript port of PureScript's [purescript-aff-retry](https://github.com/Unisay/purescript-aff-retry) package

which in turn is a porting of Haskell's [retry](https://github.com/Soostone/retry) package

# Example

```ts

import { log } from 'fp-ts/Console'

import * as E from 'fp-ts/Either'

import { pipe } from 'fp-ts/function'

import * as O from 'fp-ts/Option'

import * as TE from 'fp-ts/TaskEither'

import { capDelay, exponentialBackoff, limitRetries, Monoid, RetryStatus } from 'retry-ts'

import { retrying } from 'retry-ts/Task'

const policy = capDelay(2000, Monoid.concat(exponentialBackoff(200), limitRetries(5)))

const fakeAPI = TE.left('API errored out')

const logDelay = (status: RetryStatus) =>

  TE.rightIO(

    log(

      pipe(

        status.previousDelay,

        O.map((delay) => `retrying in ${delay} milliseconds...`),

        O.getOrElse(() => 'first attempt...')

      )

    )

  )

const result = retrying(policy, (status) => pipe(logDelay(status), TE.apSecond(fakeAPI)), E.isLeft)

result().then((e) => console.log(e))

/*

first attempt...

retrying in 200 milliseconds...  <= exponentialBackoff

retrying in 400 milliseconds...  <= exponentialBackoff

retrying in 800 milliseconds...  <= exponentialBackoff

retrying in 1600 milliseconds... <= exponentialBackoff

retrying in 2000 milliseconds... <= exponentialBackoff + capDelay

left("API errored out")          <= limitRetries

*/

```

# Documentation

- [API Reference](https://gcanti.github.io/retry-ts)

# License

The MIT License (MIT)