handler

README

handler

http.Handlers for Go

Domains

Handlers are separated into their own domains. They are:

• log - handlers used for logging purposes
  • Access - logs each request to the provided logger.
  • Panic - catches panics, logs the stack traces to a provided logger, and returns an Internal Server Error. Optionally prints the stack trace in the response body.
• encoding - handlers dealing with encoding
  • Gzip - compresses the response body
• lang - handlers for language/translation support
  • I18N - deals with language handling, redirecting to a url with a supported language code. Provides the supported languages and current one in the request context.

Example

Using the I18N handler to process a requested language.

When a user visits '/', a language will be picked from the list of supported ones, based on what the browser has set in the Accepted-Language header, or fall back to the first one in the list. If, for example, the selected language was English, a redirect will be sent to '/en/', where the final handler extracts the selected language from the request context.

package main

import (
	"net/http"

	"golang.org/x/text/language"
	"golang.org/x/text/language/display"

	"github.com/urandom/handler/lang"
)

func main() {
	handler := http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		val := r.Context().Value(lang.ContextKey).(lang.ContextValue)

		w.Write([]byte("Current language: " + display.Self.Name(val.Current)))
	})
  
	http.Handle("/", lang.I18N(handler, lang.I18NOpts{
		Languages: []language.Tag{language.German, language.French, language.English},
	}))
  
	http.ListenAndServe(":8080", nil)
}

Documentation

Overview

Package handler is a collection of useful http.Handlers

The following subpackages contain:

• log - handlers for logging requests and panics
• encoding - a handler for using gzip compression on the response
• lang - a handler for setting up i18n urls

The package itself contains some common interfaces and useful types used by all handlers.

Index

• type Logger
  • func ErrLogger() Logger
  • func NopLogger() Logger
  • func OutLogger() Logger
• type ResponseWrapper
  • func NewResponseWrapper(w http.ResponseWriter) *ResponseWrapper
  • func (w *ResponseWrapper) CloseNotify() <-chan bool
  • func (w *ResponseWrapper) Hijack() (net.Conn, *bufio.ReadWriter, error)
• type Session

Types

type Logger

type Logger interface {
	Print(v ...interface{})
}

A Logger interface is used by handlers to when some kind of output needs to be provided

func ErrLogger

func ErrLogger() Logger

ErrLogger returns a Logger implementation that outputs to os.Stderr

func NopLogger

func NopLogger() Logger

NopLogger returns a Logger implementation that does nothing

func OutLogger

func OutLogger() Logger

OutLogger returns a Logger implementation that outputs to os.Stdout

type ResponseWrapper

type ResponseWrapper struct {
	*httptest.ResponseRecorder

	// Hijacked will be set to true if the original http.ResponseWriter was
	// hijacked successfully.
	Hijacked bool
	// contains filtered or unexported fields
}

ResponseWrapper is a simple wrapper around httptest.ResponseRecorder, implementing the http.Hijacker interface.

func NewResponseWrapper

func NewResponseWrapper(w http.ResponseWriter) *ResponseWrapper

NewResponseWrapper creates a new wrapper. The passed http.ResponseWriter is used in case the wrapper needs to be hijacked.

func (*ResponseWrapper) CloseNotify

func (w *ResponseWrapper) CloseNotify() <-chan bool

CloseNotify tries to use the original http.ResponseWriter for close notification. If the original writer doesn't implement http.CloseNotifier, it returns a channel that will never close.

func (*ResponseWrapper) Hijack

func (w *ResponseWrapper) Hijack() (net.Conn, *bufio.ReadWriter, error)

Hijack tries to use the original http.ResponseWriter for hijacking. If the original writer doesn't implement http.Hijacker, it returns an error.

type Session

type Session interface {
	Get(r *http.Request, key string) (string, error)
	Set(r *http.Request, key string, value string) error
}

Session allows storing arbitrary data in between requests.