/*
Package echo implements high performance, minimalist Go web framework.
Example:
package main
import (
"net/http"
"github.com/labstack/echo/v4"
"github.com/labstack/echo/v4/middleware"
)
// Handler
func hello(c echo.Context) error {
return c.String(http.StatusOK, "Hello, World!")
}
func main() {
// Echo instance
e := echo.New()
// Middleware
e.Use(middleware.Logger())
e.Use(middleware.Recover())
// Routes
e.GET("/", hello)
// Start server
e.Logger.Fatal(e.Start(":1323"))
}
Learn more at https://echo.labstack.com
*/
package echo
import (
"bytes"
stdContext "context"
"crypto/tls"
"errors"
"fmt"
"io"
"io/ioutil"
stdLog "log"
"net"
"net/http"
"net/url"
"path"
"path/filepath"
"reflect"
"runtime"
"sync"
"time"
"github.com/labstack/gommon/color"
"github.com/labstack/gommon/log"
"golang.org/x/crypto/acme"
"golang.org/x/crypto/acme/autocert"
)
type (
// Echo is the top-level framework instance.
Echo struct {
common
StdLogger *stdLog.Logger
colorer *color.Color
premiddleware []MiddlewareFunc
middleware []MiddlewareFunc
maxParam *int
router *Router
routers map[string]*Router
notFoundHandler HandlerFunc
pool sync.Pool
Server *http.Server
TLSServer *http.Server
Listener net.Listener
TLSListener net.Listener
AutoTLSManager autocert.Manager
DisableHTTP2 bool
Debug bool
HideBanner bool
HidePort bool
HTTPErrorHandler HTTPErrorHandler
Binder Binder
Validator Validator
Renderer Renderer
Logger Logger
}
// Route contains a handler and information for matching against requests.
Route struct {
Method string `json:"method"`
Path string `json:"path"`
Name string `json:"name"`
}
// HTTPError represents an error that occurred while handling a request.
HTTPError struct {
Code int `json:"-"`
Message interface{} `json:"message"`
Internal error `json:"-"` // Stores the error returned by an external dependency
}
// MiddlewareFunc defines a function to process middleware.
MiddlewareFunc func(HandlerFunc) HandlerFunc
// HandlerFunc defines a function to serve HTTP requests.
HandlerFunc func(Context) error
// HTTPErrorHandler is a centralized HTTP error handler.
HTTPErrorHandler func(error, Context)
// Validator is the interface that wraps the Validate function.
Validator interface {
Validate(i interface{}) error
}
// Renderer is the interface that wraps the Render function.
Renderer interface {
Render(io.Writer, string, interface{}, Context) error
}
// Map defines a generic map of type `map[string]interface{}`.
Map map[string]interface{}
// Common struct for Echo & Group.
common struct{}
)
// HTTP methods
// NOTE: Deprecated, please use the stdlib constants directly instead.
const (
CONNECT = http.MethodConnect
DELETE = http.MethodDelete
GET = http.MethodGet
HEAD = http.MethodHead
OPTIONS = http.MethodOptions
PATCH = http.MethodPatch
POST = http.MethodPost
// PROPFIND = "PROPFIND"
PUT = http.MethodPut
TRACE = http.MethodTrace
)
// MIME types
const (
MIMEApplicationJSON = "application/json"
MIMEApplicationJSONCharsetUTF8 = MIMEApplicationJSON + "; " + charsetUTF8
MIMEApplicationJavaScript = "application/javascript"
MIMEApplicationJavaScriptCharsetUTF8 = MIMEApplicationJavaScript + "; " + charsetUTF8
MIMEApplicationXML = "application/xml"
MIMEApplicationXMLCharsetUTF8 = MIMEApplicationXML + "; " + charsetUTF8
MIMETextXML = "text/xml"
MIMETextXMLCharsetUTF8 = MIMETextXML + "; " + charsetUTF8
MIMEApplicationForm = "application/x-www-form-urlencoded"
MIMEApplicationProtobuf = "application/protobuf"
MIMEApplicationMsgpack = "application/msgpack"
MIMETextHTML = "text/html"
MIMETextHTMLCharsetUTF8 = MIMETextHTML + "; " + charsetUTF8
MIMETextPlain = "text/plain"
MIMETextPlainCharsetUTF8 = MIMETextPlain + "; " + charsetUTF8
MIMEMultipartForm = "multipart/form-data"
MIMEOctetStream = "application/octet-stream"
)
const (
charsetUTF8 = "charset=UTF-8"
// PROPFIND Method can be used on collection and property resources.
PROPFIND = "PROPFIND"
// REPORT Method can be used to get information about a resource, see rfc 3253
REPORT = "REPORT"
)
// Headers
const (
HeaderAccept = "Accept"
HeaderAcceptEncoding = "Accept-Encoding"
HeaderAllow = "Allow"
HeaderAuthorization = "Authorization"
HeaderContentDisposition = "Content-Disposition"
HeaderContentEncoding = "Content-Encoding"
HeaderContentLength = "Content-Length"
HeaderContentType = "Content-Type"
HeaderCookie = "Cookie"
HeaderSetCookie = "Set-Cookie"
HeaderIfModifiedSince = "If-Modified-Since"
HeaderLastModified = "Last-Modified"
HeaderLocation = "Location"
HeaderUpgrade = "Upgrade"
HeaderVary = "Vary"
HeaderWWWAuthenticate = "WWW-Authenticate"
HeaderXForwardedFor = "X-Forwarded-For"
HeaderXForwardedProto = "X-Forwarded-Proto"
HeaderXForwardedProtocol = "X-Forwarded-Protocol"
HeaderXForwardedSsl = "X-Forwarded-Ssl"
HeaderXUrlScheme = "X-Url-Scheme"
HeaderXHTTPMethodOverride = "X-HTTP-Method-Override"
HeaderXRealIP = "X-Real-IP"
HeaderXRequestID = "X-Request-ID"
HeaderXRequestedWith = "X-Requested-With"
HeaderServer = "Server"
HeaderOrigin = "Origin"
// Access control
HeaderAccessControlRequestMethod = "Access-Control-Request-Method"
HeaderAccessControlRequestHeaders = "Access-Control-Request-Headers"
HeaderAccessControlAllowOrigin = "Access-Control-Allow-Origin"
HeaderAccessControlAllowMethods = "Access-Control-Allow-Methods"
HeaderAccessControlAllowHeaders = "Access-Control-Allow-Headers"
HeaderAccessControlAllowCredentials = "Access-Control-Allow-Credentials"
HeaderAccessControlExposeHeaders = "Access-Control-Expose-Headers"
HeaderAccessControlMaxAge = "Access-Control-Max-Age"
// Security
HeaderStrictTransportSecurity = "Strict-Transport-Security"
HeaderXContentTypeOptions = "X-Content-Type-Options"
HeaderXXSSProtection = "X-XSS-Protection"
HeaderXFrameOptions = "X-Frame-Options"
HeaderContentSecurityPolicy = "Content-Security-Policy"
HeaderContentSecurityPolicyReportOnly = "Content-Security-Policy-Report-Only"
HeaderXCSRFToken = "X-CSRF-Token"
HeaderReferrerPolicy = "Referrer-Policy"
)
const (
// Version of Echo
Version = "4.1.11"
website = "https://echo.labstack.com"
// http://patorjk.com/software/taag/#p=display&f=Small%20Slant&t=Echo
banner = `
____ __
/ __/___/ / ___
/ _// __/ _ \/ _ \
/___/\__/_//_/\___/ %s
High performance, minimalist Go web framework
%s
____________________________________O/_______
O\
`
)
var (
methods = [...]string{
http.MethodConnect,
http.MethodDelete,
http.MethodGet,
http.MethodHead,
http.MethodOptions,
http.MethodPatch,
http.MethodPost,
PROPFIND,
http.MethodPut,
http.MethodTrace,
REPORT,
}
)
// Errors
var (
ErrUnsupportedMediaType = NewHTTPError(http.StatusUnsupportedMediaType)
ErrNotFound = NewHTTPError(http.StatusNotFound)
ErrUnauthorized = NewHTTPError(http.StatusUnauthorized)
ErrForbidden = NewHTTPError(http.StatusForbidden)
ErrMethodNotAllowed = NewHTTPError(http.StatusMethodNotAllowed)
ErrStatusRequestEntityTooLarge = NewHTTPError(http.StatusRequestEntityTooLarge)
ErrTooManyRequests = NewHTTPError(http.StatusTooManyRequests)
ErrBadRequest = NewHTTPError(http.StatusBadRequest)
ErrBadGateway = NewHTTPError(http.StatusBadGateway)
ErrInternalServerError = NewHTTPError(http.StatusInternalServerError)
ErrRequestTimeout = NewHTTPError(http.StatusRequestTimeout)
ErrServiceUnavailable = NewHTTPError(http.StatusServiceUnavailable)
ErrValidatorNotRegistered = errors.New("validator not registered")
ErrRendererNotRegistered = errors.New("renderer not registered")
ErrInvalidRedirectCode = errors.New("invalid redirect status code")
ErrCookieNotFound = errors.New("cookie not found")
ErrInvalidCertOrKeyType = errors.New("invalid cert or key type, must be string or []byte")
)
// Error handlers
var (
NotFoundHandler = func(c Context) error {
return ErrNotFound
}
MethodNotAllowedHandler = func(c Context) error {
return ErrMethodNotAllowed
}
)
// New creates an instance of Echo.
func New() (e *Echo) {
e = &Echo{
Server: new(http.Server),
TLSServer: new(http.Server),
AutoTLSManager: autocert.Manager{
Prompt: autocert.AcceptTOS,
},
Logger: log.New("echo"),
colorer: color.New(),
maxParam: new(int),
}
e.Server.Handler = e
e.TLSServer.Handler = e
e.HTTPErrorHandler = e.DefaultHTTPErrorHandler
e.Binder = &DefaultBinder{}
e.Logger.SetLevel(log.ERROR)
e.StdLogger = stdLog.New(e.Logger.Output(), e.Logger.Prefix()+": ", 0)
e.pool.New = func() interface{} {
return e.NewContext(nil, nil)
}
e.router = NewRouter(e)
e.routers = map[string]*Router{}
return
}
// NewContext returns a Context instance.
func (e *Echo) NewContext(r *http.Request, w http.ResponseWriter) Context {
return &context{
request: r,
response: NewResponse(w, e),
store: make(Map),
echo: e,
pvalues: make([]string, *e.maxParam),
handler: NotFoundHandler,
}
}
// Router returns the default router.
func (e *Echo) Router() *Router {
return e.router
}
// Routers returns the map of host => router.
func (e *Echo) Routers() map[string]*Router {
return e.routers
}
// DefaultHTTPErrorHandler is the default HTTP error handler. It sends a JSON response
// with status code.
func (e *Echo) DefaultHTTPErrorHandler(err error, c Context) {
he, ok := err.(*HTTPError)
if ok {
if he.Internal != nil {
if herr, ok := he.Internal.(*HTTPError); ok {
he = herr
}
}
} else {
he = &HTTPError{
Code: http.StatusInternalServerError,
Message: http.StatusText(http.StatusInternalServerError),
}
}
if e.Debug {
he.Message = err.Error()
} else if m, ok := he.Message.(string); ok {
he.Message = Map{"message": m}
}
// Send response
if !c.Response().Committed {
if c.Request().Method == http.MethodHead { // Issue #608
err = c.NoContent(he.Code)
} else {
err = c.JSON(he.Code, he.Message)
}
if err != nil {
e.Logger.Error(err)
}
}
}
// Pre adds middleware to the chain which is run before router.
func (e *Echo) Pre(middleware ...MiddlewareFunc) {
e.premiddleware = append(e.premiddleware, middleware...)
}
// Use adds middleware to the chain which is run after router.
func (e *Echo) Use(middleware ...MiddlewareFunc) {
e.middleware = append(e.middleware, middleware...)
}
// CONNECT registers a new CONNECT route for a path with matching handler in the
// router with optional route-level middleware.
func (e *Echo) CONNECT(path string, h HandlerFunc, m ...MiddlewareFunc) *Route {
return e.Add(http.MethodConnect, path, h, m...)
}
// DELETE registers a new DELETE route for a path with matching handler in the router
// with optional route-level middleware.
func (e *Echo) DELETE(path string, h HandlerFunc, m ...MiddlewareFunc) *Route {
return e.Add(http.MethodDelete, path, h, m...)
}
// GET registers a new GET route for a path with matching handler in the router
// with optional route-level middleware.
func (e *Echo) GET(path string, h HandlerFunc, m ...MiddlewareFunc) *Route {
return e.Add(http.MethodGet, path, h, m...)
}
// HEAD registers a new HEAD route for a path with matching handler in the
// router with optional route-level middleware.
func (e *Echo) HEAD(path string, h HandlerFunc, m ...MiddlewareFunc) *Route {
return e.Add(http.MethodHead, path, h, m...)
}
// OPTIONS registers a new OPTIONS route for a path with matching handler in the
// router with optional route-level middleware.
func (e *Echo) OPTIONS(path string, h HandlerFunc, m ...MiddlewareFunc) *Route {
return e.Add(http.MethodOptions, path, h, m...)
}
// PATCH registers a new PATCH route for a path with matching handler in the
// router with optional route-level middleware.
func (e *Echo) PATCH(path string, h HandlerFunc, m ...MiddlewareFunc) *Route {
return e.Add(http.MethodPatch, path, h, m...)
}
// POST registers a new POST route for a path with matching handler in the
// router with optional route-level middleware.
func (e *Echo) POST(path string, h HandlerFunc, m ...MiddlewareFunc) *Route {
return e.Add(http.MethodPost, path, h, m...)
}
// PUT registers a new PUT route for a path with matching handler in the
// router with optional route-level middleware.
func (e *Echo) PUT(path string, h HandlerFunc, m ...MiddlewareFunc) *Route {
return e.Add(http.MethodPut, path, h, m...)
}
// TRACE registers a new TRACE route for a path with matching handler in the
// router with optional route-level middleware.
func (e *Echo) TRACE(path string, h HandlerFunc, m ...MiddlewareFunc) *Route {
return e.Add(http.MethodTrace, path, h, m...)
}
// Any registers a new route for all HTTP methods and path with matching handler
// in the router with optional route-level middleware.
func (e *Echo) Any(path string, handler HandlerFunc, middleware ...MiddlewareFunc) []*Route {
routes := make([]*Route, len(methods))
for i, m := range methods {
routes[i] = e.Add(m, path, handler, middleware...)
}
return routes
}
// Match registers a new route for multiple HTTP methods and path with matching
// handler in the router with optional route-level middleware.
func (e *Echo) Match(methods []string, path string, handler HandlerFunc, middleware ...MiddlewareFunc) []*Route {
routes := make([]*Route, len(methods))
for i, m := range methods {
routes[i] = e.Add(m, path, handler, middleware...)
}
return routes
}
// Static registers a new route with path prefix to serve static files from the
// provided root directory.
func (e *Echo) Static(prefix, root string) *Route {
if root == "" {
root = "." // For security we want to restrict to CWD.
}
return e.static(prefix, root, e.GET)
}
func (common) static(prefix, root string, get func(string, HandlerFunc, ...MiddlewareFunc) *Route) *Route {
h := func(c Context) error {
p, err := url.PathUnescape(c.Param("*"))
if err != nil {
return err
}
name := filepath.Join(root, path.Clean("/"+p)) // "/"+ for security
return c.File(name)
}
if prefix == "/" {
return get(prefix+"*", h)
}
return get(prefix+"/*", h)
}
func (common) file(path, file string, get func(string, HandlerFunc, ...MiddlewareFunc) *Route,
m ...MiddlewareFunc) *Route {
return get(path, func(c Context) error {
return c.File(file)
}, m...)
}
// File registers a new route with path to serve a static file with optional route-level middleware.
func (e *Echo) File(path, file string, m ...MiddlewareFunc) *Route {
return e.file(path, file, e.GET, m...)
}
func (e *Echo) add(host, method, path string, handler HandlerFunc, middleware ...MiddlewareFunc) *Route {
name := handlerName(handler)
router := e.findRouter(host)
router.Add(method, path, func(c Context) error {
h := handler
// Chain middleware
for i := len(middleware) - 1; i >= 0; i-- {
h = middleware[i](h)
}
return h(c)
})
r := &Route{
Method: method,
Path: path,
Name: name,
}
e.router.routes[method+path] = r
return r
}
// Add registers a new route for an HTTP method and path with matching handler
// in the router with optional route-level middleware.
func (e *Echo) Add(method, path string, handler HandlerFunc, middleware ...MiddlewareFunc) *Route {
return e.add("", method, path, handler, middleware...)
}
// Host creates a new router group for the provided host and optional host-level middleware.
func (e *Echo) Host(name string, m ...MiddlewareFunc) (g *Group) {
e.routers[name] = NewRouter(e)
g = &Group{host: name, echo: e}
g.Use(m...)
return
}
// Group creates a new router group with prefix and optional group-level middleware.
func (e *Echo) Group(prefix string, m ...MiddlewareFunc) (g *Group) {
g = &Group{prefix: prefix, echo: e}
g.Use(m...)
return
}
// URI generates a URI from handler.
func (e *Echo) URI(handler HandlerFunc, params ...interface{}) string {
name := handlerName(handler)
return e.Reverse(name, params...)
}
// URL is an alias for `URI` function.
func (e *Echo) URL(h HandlerFunc, params ...interface{}) string {
return e.URI(h, params...)
}
// Reverse generates an URL from route name and provided parameters.
func (e *Echo) Reverse(name string, params ...interface{}) string {
uri := new(bytes.Buffer)
ln := len(params)
n := 0
for _, r := range e.router.routes {
if r.Name == name {
for i, l := 0, len(r.Path); i < l; i++ {
if r.Path[i] == ':' && n < ln {
for ; i < l && r.Path[i] != '/'; i++ {
}
uri.WriteString(fmt.Sprintf("%v", params[n]))
n++
}
if i < l {
uri.WriteByte(r.Path[i])
}
}
break
}
}
return uri.String()
}
// Routes returns the registered routes.
func (e *Echo) Routes() []*Route {
routes := make([]*Route, 0, len(e.router.routes))
for _, v := range e.router.routes {
routes = append(routes, v)
}
return routes
}
// AcquireContext returns an empty `Context` instance from the pool.
// You must return the context by calling `ReleaseContext()`.
func (e *Echo) AcquireContext() Context {
return e.pool.Get().(Context)
}
// ReleaseContext returns the `Context` instance back to the pool.
// You must call it after `AcquireContext()`.
func (e *Echo) ReleaseContext(c Context) {
e.pool.Put(c)
}
// ServeHTTP implements `http.Handler` interface, which serves HTTP requests.
func (e *Echo) ServeHTTP(w http.ResponseWriter, r *http.Request) {
// Acquire context
c := e.pool.Get().(*context)
c.Reset(r, w)
h := NotFoundHandler
if e.premiddleware == nil {
e.findRouter(r.Host).Find(r.Method, getPath(r), c)
h = c.Handler()
h = applyMiddleware(h, e.middleware...)
} else {
h = func(c Context) error {
e.findRouter(r.Host).Find(r.Method, getPath(r), c)
h := c.Handler()
h = applyMiddleware(h, e.middleware...)
return h(c)
}
h = applyMiddleware(h, e.premiddleware...)
}
// Execute chain
if err := h(c); err != nil {
e.HTTPErrorHandler(err, c)
}
// Release context
e.pool.Put(c)
}
// Start starts an HTTP server.
func (e *Echo) Start(address string) error {
e.Server.Addr = address
return e.StartServer(e.Server)
}
// StartTLS starts an HTTPS server.
// If `certFile` or `keyFile` is `string` the values are treated as file paths.
// If `certFile` or `keyFile` is `[]byte` the values are treated as the certificate or key as-is.
func (e *Echo) StartTLS(address string, certFile, keyFile interface{}) (err error) {
var cert []byte
if cert, err = filepathOrContent(certFile); err != nil {
return
}
var key []byte
if key, err = filepathOrContent(keyFile); err != nil {
return
}
s := e.TLSServer
s.TLSConfig = new(tls.Config)
s.TLSConfig.Certificates = make([]tls.Certificate, 1)
if s.TLSConfig.Certificates[0], err = tls.X509KeyPair(cert, key); err != nil {
return
}
return e.startTLS(address)
}
func filepathOrContent(fileOrContent interface{}) (content []byte, err error) {
switch v := fileOrContent.(type) {
case string:
return ioutil.ReadFile(v)
case []byte:
return v, nil
default:
return nil, ErrInvalidCertOrKeyType
}
}
// StartAutoTLS starts an HTTPS server using certificates automatically installed from https://letsencrypt.org.
func (e *Echo) StartAutoTLS(address string) error {
s := e.TLSServer
s.TLSConfig = new(tls.Config)
s.TLSConfig.GetCertificate = e.AutoTLSManager.GetCertificate
s.TLSConfig.NextProtos = append(s.TLSConfig.NextProtos, acme.ALPNProto)
return e.startTLS(address)
}
func (e *Echo) startTLS(address string) error {
s := e.TLSServer
s.Addr = address
if !e.DisableHTTP2 {
s.TLSConfig.NextProtos = append(s.TLSConfig.NextProtos, "h2")
}
return e.StartServer(e.TLSServer)
}
// StartServer starts a custom http server.
func (e *Echo) StartServer(s *http.Server) (err error) {
// Setup
e.colorer.SetOutput(e.Logger.Output())
s.ErrorLog = e.StdLogger
s.Handler = e
if e.Debug {
e.Logger.SetLevel(log.DEBUG)
}
if !e.HideBanner {
e.colorer.Printf(banner, e.colorer.Red("v"+Version), e.colorer.Blue(website))
}
if s.TLSConfig == nil {
if e.Listener == nil {
e.Listener, err = newListener(s.Addr)
if err != nil {
return err
}
}
if !e.HidePort {
e.colorer.Printf("⇨ http server started on %s\n", e.colorer.Green(e.Listener.Addr()))
}
return s.Serve(e.Listener)
}
if e.TLSListener == nil {
l, err := newListener(s.Addr)
if err != nil {
return err
}
e.TLSListener = tls.NewListener(l, s.TLSConfig)
}
if !e.HidePort {
e.colorer.Printf("⇨ https server started on %s\n", e.colorer.Green(e.TLSListener.Addr()))
}
return s.Serve(e.TLSListener)
}
// Close immediately stops the server.
// It internally calls `http.Server#Close()`.
func (e *Echo) Close() error {
if err := e.TLSServer.Close(); err != nil {
return err
}
return e.Server.Close()
}
// Shutdown stops the server gracefully.
// It internally calls `http.Server#Shutdown()`.
func (e *Echo) Shutdown(ctx stdContext.Context) error {
if err := e.TLSServer.Shutdown(ctx); err != nil {
return err
}
return e.Server.Shutdown(ctx)
}
// NewHTTPError creates a new HTTPError instance.
func NewHTTPError(code int, message ...interface{}) *HTTPError {
he := &HTTPError{Code: code, Message: http.StatusText(code)}
if len(message) > 0 {
he.Message = message[0]
}
return he
}
// Error makes it compatible with `error` interface.
func (he *HTTPError) Error() string {
return fmt.Sprintf("code=%d, message=%v, internal=%v", he.Code, he.Message, he.Internal)
}
// SetInternal sets error to HTTPError.Internal
func (he *HTTPError) SetInternal(err error) *HTTPError {
he.Internal = err
return he
}
// WrapHandler wraps `http.Handler` into `echo.HandlerFunc`.
func WrapHandler(h http.Handler) HandlerFunc {
return func(c Context) error {
h.ServeHTTP(c.Response(), c.Request())
return nil
}
}
// WrapMiddleware wraps `func(http.Handler) http.Handler` into `echo.MiddlewareFunc`
func WrapMiddleware(m func(http.Handler) http.Handler) MiddlewareFunc {
return func(next HandlerFunc) HandlerFunc {
return func(c Context) (err error) {
m(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
c.SetRequest(r)
c.SetResponse(NewResponse(w, c.Echo()))
err = next(c)
})).ServeHTTP(c.Response(), c.Request())
return
}
}
}
func getPath(r *http.Request) string {
path := r.URL.RawPath
if path == "" {
path = r.URL.Path
}
return path
}
func (e *Echo) findRouter(host string) *Router {
if len(e.routers) > 0 {
if r, ok := e.routers[host]; ok {
return r
}
}
return e.router
}
func handlerName(h HandlerFunc) string {
t := reflect.ValueOf(h).Type()
if t.Kind() == reflect.Func {
return runtime.FuncForPC(reflect.ValueOf(h).Pointer()).Name()
}
return t.String()
}
// // PathUnescape is wraps `url.PathUnescape`
// func PathUnescape(s string) (string, error) {
// return url.PathUnescape(s)
// }
// tcpKeepAliveListener sets TCP keep-alive timeouts on accepted
// connections. It's used by ListenAndServe and ListenAndServeTLS so
// dead TCP connections (e.g. closing laptop mid-download) eventually
// go away.
type tcpKeepAliveListener struct {
*net.TCPListener
}
func (ln tcpKeepAliveListener) Accept() (c net.Conn, err error) {
if c, err = ln.AcceptTCP(); err != nil {
return
} else if err = c.(*net.TCPConn).SetKeepAlive(true); err != nil {
return
} else if err = c.(*net.TCPConn).SetKeepAlivePeriod(3 * time.Minute); err != nil {
return
}
return
}
func newListener(address string) (*tcpKeepAliveListener, error) {
l, err := net.Listen("tcp", address)
if err != nil {
return nil, err
}
return &tcpKeepAliveListener{l.(*net.TCPListener)}, nil
}
func applyMiddleware(h HandlerFunc, middleware ...MiddlewareFunc) HandlerFunc {
for i := len(middleware) - 1; i >= 0; i-- {
h = middleware[i](h)
}
return h
}