plugeth/swarm/api/http/middleware.go

96 lines
3.2 KiB
Go

package http
import (
"fmt"
"net/http"
"runtime/debug"
"strings"
"github.com/ethereum/go-ethereum/metrics"
"github.com/ethereum/go-ethereum/swarm/api"
"github.com/ethereum/go-ethereum/swarm/log"
"github.com/ethereum/go-ethereum/swarm/spancontext"
"github.com/pborman/uuid"
)
// Adapt chains h (main request handler) main handler to adapters (middleware handlers)
// Please note that the order of execution for `adapters` is FIFO (adapters[0] will be executed first)
func Adapt(h http.Handler, adapters ...Adapter) http.Handler {
for i := range adapters {
adapter := adapters[len(adapters)-1-i]
h = adapter(h)
}
return h
}
type Adapter func(http.Handler) http.Handler
func SetRequestID(h http.Handler) http.Handler {
return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
r = r.WithContext(SetRUID(r.Context(), uuid.New()[:8]))
metrics.GetOrRegisterCounter(fmt.Sprintf("http.request.%s", r.Method), nil).Inc(1)
log.Info("created ruid for request", "ruid", GetRUID(r.Context()), "method", r.Method, "url", r.RequestURI)
h.ServeHTTP(w, r)
})
}
func ParseURI(h http.Handler) http.Handler {
return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
uri, err := api.Parse(strings.TrimLeft(r.URL.Path, "/"))
if err != nil {
w.WriteHeader(http.StatusBadRequest)
RespondError(w, r, fmt.Sprintf("invalid URI %q", r.URL.Path), http.StatusBadRequest)
return
}
if uri.Addr != "" && strings.HasPrefix(uri.Addr, "0x") {
uri.Addr = strings.TrimPrefix(uri.Addr, "0x")
msg := fmt.Sprintf(`The requested hash seems to be prefixed with '0x'. You will be redirected to the correct URL within 5 seconds.<br/>
Please click <a href='%[1]s'>here</a> if your browser does not redirect you within 5 seconds.<script>setTimeout("location.href='%[1]s';",5000);</script>`, "/"+uri.String())
w.WriteHeader(http.StatusNotFound)
w.Write([]byte(msg))
return
}
ctx := r.Context()
r = r.WithContext(SetURI(ctx, uri))
log.Debug("parsed request path", "ruid", GetRUID(r.Context()), "method", r.Method, "uri.Addr", uri.Addr, "uri.Path", uri.Path, "uri.Scheme", uri.Scheme)
h.ServeHTTP(w, r)
})
}
func InitLoggingResponseWriter(h http.Handler) http.Handler {
return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
writer := newLoggingResponseWriter(w)
h.ServeHTTP(writer, r)
log.Debug("request served", "ruid", GetRUID(r.Context()), "code", writer.statusCode)
})
}
func InstrumentOpenTracing(h http.Handler) http.Handler {
return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
uri := GetURI(r.Context())
if uri == nil || r.Method == "" || (uri != nil && uri.Scheme == "") {
h.ServeHTTP(w, r) // soft fail
return
}
spanName := fmt.Sprintf("http.%s.%s", r.Method, uri.Scheme)
ctx, sp := spancontext.StartSpan(r.Context(), spanName)
defer sp.Finish()
h.ServeHTTP(w, r.WithContext(ctx))
})
}
func RecoverPanic(h http.Handler) http.Handler {
return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
defer func() {
if err := recover(); err != nil {
log.Error("panic recovery!", "stack trace", debug.Stack(), "url", r.URL.String(), "headers", r.Header)
}
}()
h.ServeHTTP(w, r)
})
}