@http-ext/plugin-retry

A retry plugin for HttpExt.

This plugin retries failed network requests using a configurable back-off strategy.

Requirements

The plugin requires @http-ext/core and @http-ext/angular to be installed.

Installation

yarn add @http-ext/plugin-retry

or

npm install @http-ext/plugin-retry

Usage

The whole configuration object is optional.

import { HttpExtModule } from '@http-ext/angular';
import { createRetryPlugin } from '@http-ext/plugin-retry';

@NgModule({
  declarations: [AppComponent],
  imports: [
    BrowserModule,
    HttpClientModule,
    HttpExtModule.forRoot({
      plugins: [createRetryPlugin()]
    })
  ],
  bootstrap: [AppComponent]
})
export class AppModule {}

Available options

You can give a partial configuration object it will be merged with default values.

Property	Type	Default value	Description
initialIntervalMs	number	300	Duration before the first retry.
maxIntervalMs	number	10_000	Maximum time span before retrying.
maxRetries	number	3	Maximum number of retries.
shouldRetry	RetryPredicate	isServerOrUnknownError	Predicate function to know which failed request should be retried.
shouldHandleRequest	RequestCondition	() => true	Predicate function to know which request the plugin should handle.

Here is an example passing a configuration object.

Keep in mind that HTTP error is not emitted while the plugin is retrying. In the following example the HTTP error will be emitted after 10 retries, then the observable completes.

import { MemoryStorage } from '@http-ext/plugin-cache';

@NgModule({
  imports: [
    HttpExtModule.forRoot({
      plugins: [
        createRetryPlugin({
          initialIntervalMs: 500,
          maxIntervalMs: 20_000,
          maxRetries: 10,
          shouldRetry: response => response.status !== 404,
          shouldHandleRequest: ({ request }) =>
            request.url.includes('api.github.com')
        })
      ]
    })
  ]
})
export class AppModule {}