go-pulse/vendor/github.com/rs/xhandler/middleware.go
Péter Szilágyi 289b30715d Godeps, vendor: convert dependency management to trash (#3198)
This commit converts the dependency management from Godeps to the vendor
folder, also switching the tool from godep to trash. Since the upstream tool
lacks a few features proposed via a few PRs, until those PRs are merged in
(if), use github.com/karalabe/trash.

You can update dependencies via trash --update.

All dependencies have been updated to their latest version.

Parts of the build system are reworked to drop old notions of Godeps and
invocation of the go vet command so that it doesn't run against the vendor
folder, as that will just blow up during vetting.

The conversion drops OpenCL (and hence GPU mining support) from ethash and our
codebase. The short reasoning is that there's noone to maintain and having
opencl libs in our deps messes up builds as go install ./... tries to build
them, failing with unsatisfied link errors for the C OpenCL deps.

golang.org/x/net/context is not vendored in. We expect it to be fetched by the
user (i.e. using go get). To keep ci.go builds reproducible the package is
"vendored" in build/_vendor.
2016-10-28 19:05:01 +02:00

60 lines
1.7 KiB
Go

package xhandler
import (
"net/http"
"time"
"golang.org/x/net/context"
)
// CloseHandler returns a Handler, cancelling the context when the client
// connection closes unexpectedly.
func CloseHandler(next HandlerC) HandlerC {
return HandlerFuncC(func(ctx context.Context, w http.ResponseWriter, r *http.Request) {
// Cancel the context if the client closes the connection
if wcn, ok := w.(http.CloseNotifier); ok {
var cancel context.CancelFunc
ctx, cancel = context.WithCancel(ctx)
defer cancel()
notify := wcn.CloseNotify()
go func() {
select {
case <-notify:
cancel()
case <-ctx.Done():
}
}()
}
next.ServeHTTPC(ctx, w, r)
})
}
// TimeoutHandler returns a Handler which adds a timeout to the context.
//
// Child handlers have the responsability of obeying the context deadline and to return
// an appropriate error (or not) response in case of timeout.
func TimeoutHandler(timeout time.Duration) func(next HandlerC) HandlerC {
return func(next HandlerC) HandlerC {
return HandlerFuncC(func(ctx context.Context, w http.ResponseWriter, r *http.Request) {
ctx, _ = context.WithTimeout(ctx, timeout)
next.ServeHTTPC(ctx, w, r)
})
}
}
// If is a special handler that will skip insert the condNext handler only if a condition
// applies at runtime.
func If(cond func(ctx context.Context, w http.ResponseWriter, r *http.Request) bool, condNext func(next HandlerC) HandlerC) func(next HandlerC) HandlerC {
return func(next HandlerC) HandlerC {
return HandlerFuncC(func(ctx context.Context, w http.ResponseWriter, r *http.Request) {
if cond(ctx, w, r) {
condNext(next).ServeHTTPC(ctx, w, r)
} else {
next.ServeHTTPC(ctx, w, r)
}
})
}
}