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* Adds a test case for the repro given in issue #534 * Fixes the logic in CORSMethodMiddleware to handle matching routes better
package mux | |
import ( | |
"net/http" | |
"strings" | |
) | |
// MiddlewareFunc is a function which receives an http.Handler and returns another http.Handler. | |
// Typically, the returned handler is a closure which does something with the http.ResponseWriter and http.Request passed | |
// to it, and then calls the handler passed as parameter to the MiddlewareFunc. | |
type MiddlewareFunc func(http.Handler) http.Handler | |
// middleware interface is anything which implements a MiddlewareFunc named Middleware. | |
type middleware interface { | |
Middleware(handler http.Handler) http.Handler | |
} | |
// Middleware allows MiddlewareFunc to implement the middleware interface. | |
func (mw MiddlewareFunc) Middleware(handler http.Handler) http.Handler { | |
return mw(handler) | |
} | |
// Use appends a MiddlewareFunc to the chain. Middleware can be used to intercept or otherwise modify requests and/or responses, and are executed in the order that they are applied to the Router. | |
func (r *Router) Use(mwf ...MiddlewareFunc) { | |
for _, fn := range mwf { | |
r.middlewares = append(r.middlewares, fn) | |
} | |
} | |
// useInterface appends a middleware to the chain. Middleware can be used to intercept or otherwise modify requests and/or responses, and are executed in the order that they are applied to the Router. | |
func (r *Router) useInterface(mw middleware) { | |
r.middlewares = append(r.middlewares, mw) | |
} | |
// CORSMethodMiddleware automatically sets the Access-Control-Allow-Methods response header | |
// on requests for routes that have an OPTIONS method matcher to all the method matchers on | |
// the route. Routes that do not explicitly handle OPTIONS requests will not be processed | |
// by the middleware. See examples for usage. | |
func CORSMethodMiddleware(r *Router) MiddlewareFunc { | |
return func(next http.Handler) http.Handler { | |
return http.HandlerFunc(func(w http.ResponseWriter, req *http.Request) { | |
allMethods, err := getAllMethodsForRoute(r, req) | |
if err == nil { | |
for _, v := range allMethods { | |
if v == http.MethodOptions { | |
w.Header().Set("Access-Control-Allow-Methods", strings.Join(allMethods, ",")) | |
} | |
} | |
} | |
next.ServeHTTP(w, req) | |
}) | |
} | |
} | |
// getAllMethodsForRoute returns all the methods from method matchers matching a given | |
// request. | |
func getAllMethodsForRoute(r *Router, req *http.Request) ([]string, error) { | |
var allMethods []string | |
for _, route := range r.routes { | |
var match RouteMatch | |
if route.Match(req, &match) || match.MatchErr == ErrMethodMismatch { | |
methods, err := route.GetMethods() | |
if err != nil { | |
return nil, err | |
} | |
allMethods = append(allMethods, methods...) | |
} | |
} | |
return allMethods, nil | |
} |