2020-04-20 04:23:05 +08:00
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go-retryablehttp
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================
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[![Build Status](http://img.shields.io/travis/hashicorp/go-retryablehttp.svg?style=flat-square)][travis]
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[![Go Documentation](http://img.shields.io/badge/go-documentation-blue.svg?style=flat-square)][godocs]
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[travis]: http://travis-ci.org/hashicorp/go-retryablehttp
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[godocs]: http://godoc.org/github.com/hashicorp/go-retryablehttp
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The `retryablehttp` package provides a familiar HTTP client interface with
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automatic retries and exponential backoff. It is a thin wrapper over the
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standard `net/http` client library and exposes nearly the same public API. This
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makes `retryablehttp` very easy to drop into existing programs.
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`retryablehttp` performs automatic retries under certain conditions. Mainly, if
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an error is returned by the client (connection errors, etc.), or if a 500-range
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response code is received (except 501), then a retry is invoked after a wait
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period. Otherwise, the response is returned and left to the caller to
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interpret.
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The main difference from `net/http` is that requests which take a request body
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(POST/PUT et. al) can have the body provided in a number of ways (some more or
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less efficient) that allow "rewinding" the request body if the initial request
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fails so that the full request can be attempted again. See the
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[godoc](http://godoc.org/github.com/hashicorp/go-retryablehttp) for more
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details.
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Version 0.6.0 and before are compatible with Go prior to 1.12. From 0.6.1 onward, Go 1.12+ is required.
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2020-11-07 02:41:42 +08:00
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From 0.6.7 onward, Go 1.13+ is required.
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2020-04-20 04:23:05 +08:00
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Example Use
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===========
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Using this library should look almost identical to what you would do with
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`net/http`. The most simple example of a GET request is shown below:
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```go
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resp, err := retryablehttp.Get("/foo")
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if err != nil {
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panic(err)
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}
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```
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The returned response object is an `*http.Response`, the same thing you would
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usually get from `net/http`. Had the request failed one or more times, the above
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call would block and retry with exponential backoff.
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## Getting a stdlib `*http.Client` with retries
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It's possible to convert a `*retryablehttp.Client` directly to a `*http.Client`.
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This makes use of retryablehttp broadly applicable with minimal effort. Simply
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configure a `*retryablehttp.Client` as you wish, and then call `StandardClient()`:
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```go
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retryClient := retryablehttp.NewClient()
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retryClient.RetryMax = 10
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standardClient := retryClient.StandardClient() // *http.Client
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```
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For more usage and examples see the
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[godoc](http://godoc.org/github.com/hashicorp/go-retryablehttp).
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