s3 test get w/ If-Match: bogus ETag

weed/s3api/s3api_object_handlers.go

@@ -333,6 +333,11 @@ func (s3a *S3ApiServer) proxyToFiler(w http.ResponseWriter, r *http.Request, des
 	}
 	defer util.CloseResponse(resp)
 
+	if resp.StatusCode == http.StatusPreconditionFailed {
+		writeErrorResponse(w, s3err.ErrPreconditionFailed, r.URL)
+		return
+	}
+
 	if (resp.ContentLength == -1 || resp.StatusCode == 404) && resp.StatusCode != 304 {
 		if r.Method != "DELETE" {
 			writeErrorResponse(w, s3err.ErrNoSuchKey, r.URL)

weed/s3api/s3err/s3api_errors.go

@@ -93,6 +93,7 @@ const (
 	ErrInvalidRequest
 	ErrAuthNotSetup
 	ErrNotImplemented
+	ErrPreconditionFailed
 
 	ErrExistingObjectIsDirectory
 )
@@ -342,7 +343,7 @@ var errorCodeResponse = map[ErrorCode]APIError{
 		Description:    "Invalid Request",
 		HTTPStatusCode: http.StatusBadRequest,
 	},
-	ErrAuthNotSetup : {
+	ErrAuthNotSetup: {
 		Code:           "InvalidRequest",
 		Description:    "Signed request requires setting up SeaweedFS S3 authentication",
 		HTTPStatusCode: http.StatusBadRequest,
@@ -352,6 +353,11 @@ var errorCodeResponse = map[ErrorCode]APIError{
 		Description:    "A header you provided implies functionality that is not implemented",
 		HTTPStatusCode: http.StatusNotImplemented,
 	},
+	ErrPreconditionFailed: {
+		Code:           "PreconditionFailed",
+		Description:    "At least one of the pre-conditions you specified did not hold",
+		HTTPStatusCode: http.StatusPreconditionFailed,
+	},
 	ErrExistingObjectIsDirectory: {
 		Code:           "ExistingObjectIsDirectory",
 		Description:    "Existing Object is a directory.",

weed/server/filer_server_handlers_read.go

@@ -61,6 +61,13 @@ func (fs *FilerServer) GetOrHeadHandler(w http.ResponseWriter, r *http.Request,
 		return
 	}
 
+	// set etag
+	etag := filer.ETagEntry(entry)
+	if ifm := r.Header.Get("If-Match"); ifm != "" && ifm != "\""+etag+"\"" {
+		w.WriteHeader(http.StatusPreconditionFailed)
+		return
+	}
+
 	w.Header().Set("Accept-Ranges", "bytes")
 
 	// mime type
@@ -115,8 +122,6 @@ func (fs *FilerServer) GetOrHeadHandler(w http.ResponseWriter, r *http.Request,
 		}
 	}
 
-	// set etag
-	etag := filer.ETagEntry(entry)
 	if inm := r.Header.Get("If-None-Match"); inm == "\""+etag+"\"" {
 		w.WriteHeader(http.StatusNotModified)
 		return