This commit is contained in:
root 2022-02-08 10:13:19 +08:00
parent 433fde4b18
commit 7f0c793083
2 changed files with 64 additions and 20 deletions

View file

@ -21,6 +21,64 @@ import (
"github.com/chrislusf/seaweedfs/weed/util" "github.com/chrislusf/seaweedfs/weed/util"
) )
// Validates the preconditions. Returns true if GET/HEAD operation should not proceed.
// Preconditions supported are:
// If-Modified-Since
// If-Unmodified-Since
// If-Match
// If-None-Match
func checkPreconditions(w http.ResponseWriter, r *http.Request, entry *filer.Entry) bool {
etag := filer.ETagEntry(entry)
/// When more than one conditional request header field is present in a
/// request, the order in which the fields are evaluated becomes
/// important. In practice, the fields defined in this document are
/// consistently implemented in a single, logical order, since "lost
/// update" preconditions have more strict requirements than cache
/// validation, a validated cache is more efficient than a partial
/// response, and entity tags are presumed to be more accurate than date
/// validators. https://tools.ietf.org/html/rfc7232#section-5
if entry.Attr.Mtime.IsZero() {
return false
}
w.Header().Set("Last-Modified", entry.Attr.Mtime.UTC().Format(http.TimeFormat))
ifMatchETagHeader := r.Header.Get("If-Match")
ifUnmodifiedSinceHeader := r.Header.Get("If-Unmodified-Since")
if ifMatchETagHeader != "" {
if util.CanonicalizeETag(etag) != util.CanonicalizeETag(ifMatchETagHeader) {
w.WriteHeader(http.StatusPreconditionFailed)
return true
}
} else if ifUnmodifiedSinceHeader != "" {
if t, parseError := time.Parse(http.TimeFormat, ifUnmodifiedSinceHeader); parseError == nil {
if t.Before(entry.Attr.Mtime) {
w.WriteHeader(http.StatusPreconditionFailed)
return true
}
}
}
ifNoneMatchETagHeader := r.Header.Get("If-None-Match")
ifModifiedSinceHeader := r.Header.Get("If-Modified-Since")
if ifNoneMatchETagHeader != "" {
if util.CanonicalizeETag(etag) == util.CanonicalizeETag(ifNoneMatchETagHeader) {
w.WriteHeader(http.StatusNotModified)
return true
}
} else if ifModifiedSinceHeader != "" {
if t, parseError := time.Parse(http.TimeFormat, ifModifiedSinceHeader); parseError == nil {
if t.After(entry.Attr.Mtime) {
w.WriteHeader(http.StatusNotModified)
return true
}
}
}
return false
}
func (fs *FilerServer) GetOrHeadHandler(w http.ResponseWriter, r *http.Request) { func (fs *FilerServer) GetOrHeadHandler(w http.ResponseWriter, r *http.Request) {
path := r.URL.Path path := r.URL.Path
@ -61,10 +119,8 @@ func (fs *FilerServer) GetOrHeadHandler(w http.ResponseWriter, r *http.Request)
return return
} }
// set etag
etag := filer.ETagEntry(entry) etag := filer.ETagEntry(entry)
if ifm := r.Header.Get("If-Match"); ifm != "" && (ifm != "\""+etag+"\"" && ifm != etag) { if checkPreconditions(w, r, entry) {
w.WriteHeader(http.StatusPreconditionFailed)
return return
} }
@ -81,19 +137,6 @@ func (fs *FilerServer) GetOrHeadHandler(w http.ResponseWriter, r *http.Request)
w.Header().Set("Content-Type", mimeType) w.Header().Set("Content-Type", mimeType)
} }
// if modified since
if !entry.Attr.Mtime.IsZero() {
w.Header().Set("Last-Modified", entry.Attr.Mtime.UTC().Format(http.TimeFormat))
if r.Header.Get("If-Modified-Since") != "" {
if t, parseError := time.Parse(http.TimeFormat, r.Header.Get("If-Modified-Since")); parseError == nil {
if !t.Before(entry.Attr.Mtime) {
w.WriteHeader(http.StatusNotModified)
return
}
}
}
}
// print out the header from extended properties // print out the header from extended properties
for k, v := range entry.Extended { for k, v := range entry.Extended {
if !strings.HasPrefix(k, "xattr-") { if !strings.HasPrefix(k, "xattr-") {
@ -123,10 +166,6 @@ func (fs *FilerServer) GetOrHeadHandler(w http.ResponseWriter, r *http.Request)
w.Header().Set(xhttp.AmzTagCount, strconv.Itoa(tagCount)) w.Header().Set(xhttp.AmzTagCount, strconv.Itoa(tagCount))
} }
if inm := r.Header.Get("If-None-Match"); inm == "\""+etag+"\"" {
w.WriteHeader(http.StatusNotModified)
return
}
setEtag(w, etag) setEtag(w, etag)
filename := entry.Name() filename := entry.Name()

View file

@ -61,3 +61,8 @@ func ParseHostPort(hostPort string) (filerServer string, filerPort int64, err er
return return
} }
func CanonicalizeETag(etag string) string {
canonicalETag := strings.TrimPrefix(etag, "\"")
return strings.TrimSuffix(canonicalETag, "\"")
}