refactor

weed/s3api/s3err/error_handler.go

@@ -0,0 +1,81 @@
+package s3err
+
+import (
+	"bytes"
+	"encoding/xml"
+	"fmt"
+	"github.com/chrislusf/seaweedfs/weed/glog"
+	"net/http"
+	"strconv"
+	"time"
+)
+
+type mimeType string
+
+const (
+	mimeNone mimeType = ""
+	MimeXML  mimeType = "application/xml"
+)
+
+func WriteXMLResponse(w http.ResponseWriter, statusCode int, response interface{}) {
+	WriteResponse(w, statusCode, EncodeXMLResponse(response), MimeXML)
+}
+
+func WriteEmptyResponse(w http.ResponseWriter, statusCode int) {
+	WriteResponse(w, statusCode, []byte{}, mimeNone)
+}
+
+func WriteErrorResponse(w http.ResponseWriter, errorCode ErrorCode, r *http.Request) {
+	apiError := GetAPIError(errorCode)
+	errorResponse := getRESTErrorResponse(apiError, r.URL.Path)
+	encodedErrorResponse := EncodeXMLResponse(errorResponse)
+	WriteResponse(w, apiError.HTTPStatusCode, encodedErrorResponse, MimeXML)
+}
+
+func getRESTErrorResponse(err APIError, resource string) RESTErrorResponse {
+	return RESTErrorResponse{
+		Code:      err.Code,
+		Message:   err.Description,
+		Resource:  resource,
+		RequestID: fmt.Sprintf("%d", time.Now().UnixNano()),
+	}
+}
+
+// Encodes the response headers into XML format.
+func EncodeXMLResponse(response interface{}) []byte {
+	var bytesBuffer bytes.Buffer
+	bytesBuffer.WriteString(xml.Header)
+	e := xml.NewEncoder(&bytesBuffer)
+	e.Encode(response)
+	return bytesBuffer.Bytes()
+}
+
+func setCommonHeaders(w http.ResponseWriter) {
+	w.Header().Set("x-amz-request-id", fmt.Sprintf("%d", time.Now().UnixNano()))
+	w.Header().Set("Accept-Ranges", "bytes")
+}
+
+func WriteResponse(w http.ResponseWriter, statusCode int, response []byte, mType mimeType) {
+	setCommonHeaders(w)
+	if response != nil {
+		w.Header().Set("Content-Length", strconv.Itoa(len(response)))
+	}
+	if mType != mimeNone {
+		w.Header().Set("Content-Type", string(mType))
+	}
+	w.WriteHeader(statusCode)
+	if response != nil {
+		glog.V(4).Infof("status %d %s: %s", statusCode, mType, string(response))
+		_, err := w.Write(response)
+		if err != nil {
+			glog.V(0).Infof("write err: %v", err)
+		}
+		w.(http.Flusher).Flush()
+	}
+}
+
+// If none of the http routes match respond with MethodNotAllowed
+func NotFoundHandler(w http.ResponseWriter, r *http.Request) {
+	glog.V(0).Infof("unsupported %s %s", r.Method, r.RequestURI)
+	WriteErrorResponse(w, ErrMethodNotAllowed, r)
+}