Echo Etag Middleware

Etag middleware for Echo Framework

Features

• Support Etag and Weak Etag
• Support Skipper
• Configurable Hash Function (default: sha256 for Etag and crc32 for Weak Etag) Any hash function that implements the hash.Hash interface can be used.

BEWARE: Creating an Etag will buffer the entire response body. This may consume a lot of memory if the response body is large (files). If this is a concern, you should use the Skipper option to skip Etag generation for large responses and use other method of caching, for example: Last-Modified header.

Installation

$ go get github.com/pablor21/echo-etag/v4

Usage

package main

import (
    "github.com/labstack/echo/v4"
    etag "github.com/pablor21/echo-etag/v4"
)

func main() {
    e := echo.New()

    //Etag middleware
    e.Use(etag.Etag())

    e.Start(":1323")
}

Example

package main

import (
    "github.com/labstack/echo/v4"
    etag "github.com/pablor21/echo-etag/v4"
)

func main() {
    e := echo.New()

    //Etag middleware
    e.Use(etag.Etag())

    e.GET("/", func(c echo.Context) error {
        return c.String(200, "Hello, World!")
    })

    e.Start(":1323")
}

Configuration

package main

import (
    "crypto/md5"
    "github.com/labstack/echo/v4"
    etag "github.com/pablor21/echo-etag/v4"
)

func main() {
    e := echo.New()

    //Etag middleware
    e.Use(etag.WithConfig(etag.Config{
        Skipper: func(c echo.Context) bool {
            return c.Path() == "/skip"
        },
        Weak: true,
        HashFn: func(config etag.Config) hash.Hash {
            return md5.New() //use md5 hash
		},
    }))

    e.GET("/", func(c echo.Context) error {
        return c.String(200, "Hello, World!")
    })

    e.Start(":1323")
}

License

MIT License