cors

Documentation

Overview

Package cors is net/http handler to handle CORS related requests as defined by http://www.w3.org/TR/cors/

You can configure it by passing an option struct to cors.New:

c := cors.New(cors.Options{
    AllowedOrigins:   []string{"foo.com"},
    AllowedMethods:   []string{http.MethodGet, http.MethodPost, http.MethodDelete},
    AllowCredentials: true,
})

Then insert the handler in the chain:

handler = c.Handler(handler)

See Options documentation for more options.

The resulting handler is a standard net/http handler.

Index

• func ConvertCanonicalHeaderKey(s []string) []string
• func ConvertToUpper(s []string) []string
• type Cors
  • func AllowAll() *Cors
  • func Default() *Cors
  • func New(options Options) *Cors
  • func (c *Cors) Handler(h http.Handler) http.Handler
  • func (c *Cors) HandlerFunc(w http.ResponseWriter, r *http.Request)
  • func (c *Cors) ServeHTTP(w http.ResponseWriter, r *http.Request, next http.HandlerFunc)
• type Logger
• type Options

Functions

func ConvertCanonicalHeaderKey

func ConvertCanonicalHeaderKey(s []string) []string

func ConvertToUpper

func ConvertToUpper(s []string) []string

Types

type Cors

type Cors struct {
	// Debug logger
	Log Logger
	// contains filtered or unexported fields
}

Cors http handler

func AllowAll

func AllowAll() *Cors

AllowAll create a new Cors handler with permissive configuration allowing all origins with all standard methods with any header and credentials.

func Default

func Default() *Cors

Default creates a new Cors handler with default options.

func New

func New(options Options) *Cors

New creates a new Cors handler with the provided options.

func (*Cors) Handler

func (c *Cors) Handler(h http.Handler) http.Handler

Handler apply the CORS specification on the request, and add relevant CORS headers as necessary.

func (*Cors) HandlerFunc

func (c *Cors) HandlerFunc(w http.ResponseWriter, r *http.Request)

HandlerFunc provides Martini compatible handler

func (*Cors) ServeHTTP

func (c *Cors) ServeHTTP(w http.ResponseWriter, r *http.Request, next http.HandlerFunc)

Negroni compatible interface

type Logger

type Logger interface {
	Printf(string, ...interface{})
}

Logger generic interface for logger

type Options

type Options struct {
	// AllowedOrigins is a list of origins a cross-domain request can be executed from.
	// If the special "*" value is present in the list, all origins will be allowed.
	// An origin may contain a wildcard (*) to replace 0 or more characters
	// (i.e.: http://*.domain.com). Usage of wildcards implies a small performance penalty.
	// Only one wildcard can be used per origin.
	// Default value is ["*"]
	AllowedOrigins []string
	// AllowOriginFunc is a custom function to validate the origin. It take the origin
	// as argument and returns true if allowed or false otherwise. If this option is
	// set, the content of AllowedOrigins is ignored.
	AllowOriginFunc func(origin string) bool
	// AllowOriginFunc is a custom function to validate the origin. It takes the HTTP Request object and the origin as
	// argument and returns true if allowed or false otherwise. If this option is set, the content of `AllowedOrigins`
	// and `AllowOriginFunc` is ignored.
	AllowOriginRequestFunc func(r *http.Request, origin string) bool
	// AllowedMethods is a list of methods the client is allowed to use with
	// cross-domain requests. Default value is simple methods (HEAD, GET and POST).
	AllowedMethods []string
	// AllowedHeaders is list of non simple headers the client is allowed to use with
	// cross-domain requests.
	// If the special "*" value is present in the list, all headers will be allowed.
	// Default value is [] but "Origin" is always appended to the list.
	AllowedHeaders []string
	// ExposedHeaders indicates which headers are safe to expose to the API of a CORS
	// API specification
	ExposedHeaders []string
	// MaxAge indicates how long (in seconds) the results of a preflight request
	// can be cached
	MaxAge int
	// AllowCredentials indicates whether the request can include user credentials like
	// cookies, HTTP authentication or client side SSL certificates.
	AllowCredentials bool
	// OptionsPassthrough instructs preflight to let other potential next handlers to
	// process the OPTIONS method. Turn this on if your application handles OPTIONS.
	OptionsPassthrough bool
	// Debugging flag adds additional output to debug server side CORS issues
	Debug bool
}

Options is a configuration container to setup the CORS middleware.