116 lines
2.6 KiB
Go
116 lines
2.6 KiB
Go
// Copyright 2025 The Go Authors. All rights reserved.
|
|
// Use of this source code is governed by a BSD-style
|
|
// license that can be found in the LICENSE file.
|
|
|
|
package httpcommon
|
|
|
|
import (
|
|
"net/http"
|
|
"sync"
|
|
)
|
|
|
|
var (
|
|
commonBuildOnce sync.Once
|
|
commonLowerHeader map[string]string // Go-Canonical-Case -> lower-case
|
|
commonCanonHeader map[string]string // lower-case -> Go-Canonical-Case
|
|
)
|
|
|
|
func buildCommonHeaderMapsOnce() {
|
|
commonBuildOnce.Do(buildCommonHeaderMaps)
|
|
}
|
|
|
|
func buildCommonHeaderMaps() {
|
|
common := []string{
|
|
"accept",
|
|
"accept-charset",
|
|
"accept-encoding",
|
|
"accept-language",
|
|
"accept-ranges",
|
|
"age",
|
|
"access-control-allow-credentials",
|
|
"access-control-allow-headers",
|
|
"access-control-allow-methods",
|
|
"access-control-allow-origin",
|
|
"access-control-expose-headers",
|
|
"access-control-max-age",
|
|
"access-control-request-headers",
|
|
"access-control-request-method",
|
|
"allow",
|
|
"authorization",
|
|
"cache-control",
|
|
"content-disposition",
|
|
"content-encoding",
|
|
"content-language",
|
|
"content-length",
|
|
"content-location",
|
|
"content-range",
|
|
"content-type",
|
|
"cookie",
|
|
"date",
|
|
"etag",
|
|
"expect",
|
|
"expires",
|
|
"from",
|
|
"host",
|
|
"if-match",
|
|
"if-modified-since",
|
|
"if-none-match",
|
|
"if-unmodified-since",
|
|
"last-modified",
|
|
"link",
|
|
"location",
|
|
"max-forwards",
|
|
"origin",
|
|
"proxy-authenticate",
|
|
"proxy-authorization",
|
|
"range",
|
|
"referer",
|
|
"refresh",
|
|
"retry-after",
|
|
"server",
|
|
"set-cookie",
|
|
"strict-transport-security",
|
|
"trailer",
|
|
"transfer-encoding",
|
|
"user-agent",
|
|
"vary",
|
|
"via",
|
|
"www-authenticate",
|
|
"x-forwarded-for",
|
|
"x-forwarded-proto",
|
|
}
|
|
commonLowerHeader = make(map[string]string, len(common))
|
|
commonCanonHeader = make(map[string]string, len(common))
|
|
for _, v := range common {
|
|
chk := http.CanonicalHeaderKey(v)
|
|
commonLowerHeader[chk] = v
|
|
commonCanonHeader[v] = chk
|
|
}
|
|
}
|
|
|
|
// LowerHeader returns the lowercase form of a header name,
|
|
// used on the wire for HTTP/2 and HTTP/3 requests.
|
|
func LowerHeader(v string) (lower string, ascii bool) {
|
|
buildCommonHeaderMapsOnce()
|
|
if s, ok := commonLowerHeader[v]; ok {
|
|
return s, true
|
|
}
|
|
return asciiToLower(v)
|
|
}
|
|
|
|
// CanonicalHeader canonicalizes a header name. (For example, "host" becomes "Host".)
|
|
func CanonicalHeader(v string) string {
|
|
buildCommonHeaderMapsOnce()
|
|
if s, ok := commonCanonHeader[v]; ok {
|
|
return s
|
|
}
|
|
return http.CanonicalHeaderKey(v)
|
|
}
|
|
|
|
// CachedCanonicalHeader returns the canonical form of a well-known header name.
|
|
func CachedCanonicalHeader(v string) (string, bool) {
|
|
buildCommonHeaderMapsOnce()
|
|
s, ok := commonCanonHeader[v]
|
|
return s, ok
|
|
}
|