httpcache

README

HTTPcache

HTTPcache is a fast, local cache for HTTP requests and responses and wraps the default http.RoundTripper from Go standard library.

Features

HTTPcache has a few useful features:

• Store and retrieve HTTP responses for any type of request.
• Expire responses after a customisable time duration.
• Decide when to store responses based on status code.

If you want to request a feature then open a GitHub Issue today!

Quick Start

This module can be installed using the command line:

go get -u github.com/alexmerren/httpcache

Here's an example of using the httpcache module to cache responses:

package main

func main() {
    // Create a new cached round tripper that:
    // * Only stores responses with status code 200.
    // * Refuses to store responses with status code 404. 
    cache := httpcache.NewCachedRoundTripper(
        httpcache.WithAllowedStatusCodes([]int{200}),
        httpcache.WithDeniedStatusCodes([]int{404}),
    )

    // Create HTTP client with cached round tripper.
    httpClient := &http.Client{
        Transport: cache,
    }

    // Do first request to populate local database.
    httpClient.Get("https://www.google.com") 

    // Subsequent requests read from database with no outgoing HTTP request.
    for _ = range 10 {
        response, _ = httpClient.Get("https://www.google.com")
        defer response.Body.Close()
        responseBody = io.ReadAll(response.body)

        fmt.Println(responseBody)
    }
}

❓ Questions and Support

Any questions can be submitted via GitHub Issues. Feel free to start contributing or asking any questions required!

Documentation

Index

• Variables
• func WithAllowedStatusCodes(allowedStatusCodes []int) func(*CachedRoundTripper)
• func WithCacheStore(store ResponseStorer) func(*CachedRoundTripper)
• func WithDeniedStatusCodes(deniedStatusCodes []int) func(*CachedRoundTripper)
• func WithExpiryTime(expiryTime time.Duration) func(*CachedRoundTripper)
• func WithName(name string) func(*CachedRoundTripper)
• type CachedRoundTripper
  • func NewCachedRoundTripper(options ...func(*CachedRoundTripper)) *CachedRoundTripper
  • func (h *CachedRoundTripper) RoundTrip(request *http.Request) (*http.Response, error)
• type ResponseStorer

Variables

var (
	ErrNoResponse = errors.New("no stored response")
)

Functions

func WithAllowedStatusCodes

func WithAllowedStatusCodes(allowedStatusCodes []int) func(*CachedRoundTripper)

func WithCacheStore

func WithCacheStore(store ResponseStorer) func(*CachedRoundTripper)

func WithDeniedStatusCodes

func WithDeniedStatusCodes(deniedStatusCodes []int) func(*CachedRoundTripper)

func WithExpiryTime

func WithExpiryTime(expiryTime time.Duration) func(*CachedRoundTripper)

func WithName

func WithName(name string) func(*CachedRoundTripper)

Types

type CachedRoundTripper

type CachedRoundTripper struct {
	// contains filtered or unexported fields
}

func NewCachedRoundTripper

func NewCachedRoundTripper(options ...func(*CachedRoundTripper)) *CachedRoundTripper

func (*CachedRoundTripper) RoundTrip

func (h *CachedRoundTripper) RoundTrip(request *http.Request) (*http.Response, error)

type ResponseStorer

type ResponseStorer interface {
	Save(response *http.Response) error
	Read(request *http.Request) (*http.Response, error)
	SaveContext(ctx context.Context, response *http.Response) error
	ReadContext(ctx context.Context, request *http.Request) (*http.Response, error)
}