minio/pkg/server/api/headers.go

112 lines
3.3 KiB
Go

/*
* Minio Cloud Storage, (C) 2015 Minio, Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package api
import (
"bytes"
"crypto/rand"
"encoding/json"
"encoding/xml"
"net/http"
"strconv"
"github.com/minio/minio/pkg/donut"
)
// No encoder interface exists, so we create one.
type encoder interface {
Encode(v interface{}) error
}
//// helpers
// Static alphaNumeric table used for generating unique request ids
var alphaNumericTable = []byte("0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ")
// generateRequestID generate request id
func generateRequestID() []byte {
alpha := make([]byte, 16)
rand.Read(alpha)
for i := 0; i < 16; i++ {
alpha[i] = alphaNumericTable[alpha[i]%byte(len(alphaNumericTable))]
}
return alpha
}
// Write http common headers
func setCommonHeaders(w http.ResponseWriter, acceptsType string, contentLength int) {
// set unique request ID for each reply
w.Header().Set("X-Amz-Request-Id", string(generateRequestID()))
w.Header().Set("Server", "Minio")
w.Header().Set("Accept-Ranges", "bytes")
w.Header().Set("Content-Type", acceptsType)
w.Header().Set("Connection", "close")
// should be set to '0' by default
w.Header().Set("Content-Length", strconv.Itoa(contentLength))
}
// Write error response headers
func encodeErrorResponse(response interface{}, acceptsType contentType) []byte {
var bytesBuffer bytes.Buffer
var encoder encoder
// write common headers
switch acceptsType {
case xmlContentType:
encoder = xml.NewEncoder(&bytesBuffer)
case jsonContentType:
encoder = json.NewEncoder(&bytesBuffer)
// by default even if unknown Accept header received handle it by sending XML contenttype response
default:
encoder = xml.NewEncoder(&bytesBuffer)
}
encoder.Encode(response)
return bytesBuffer.Bytes()
}
// Write object header
func setObjectHeaders(w http.ResponseWriter, metadata donut.ObjectMetadata) {
lastModified := metadata.Created.Format(http.TimeFormat)
// common headers
setCommonHeaders(w, metadata.Metadata["contentType"], int(metadata.Size))
// object related headers
w.Header().Set("ETag", "\""+metadata.MD5Sum+"\"")
w.Header().Set("Last-Modified", lastModified)
}
// Write range object header
func setRangeObjectHeaders(w http.ResponseWriter, metadata donut.ObjectMetadata, contentRange *httpRange) {
// set common headers
setCommonHeaders(w, metadata.Metadata["contentType"], int(metadata.Size))
// set object headers
setObjectHeaders(w, metadata)
// set content range
w.Header().Set("Content-Range", contentRange.getContentRange())
}
func encodeSuccessResponse(response interface{}, acceptsType contentType) []byte {
var encoder encoder
var bytesBuffer bytes.Buffer
switch acceptsType {
case xmlContentType:
encoder = xml.NewEncoder(&bytesBuffer)
case jsonContentType:
encoder = json.NewEncoder(&bytesBuffer)
}
encoder.Encode(response)
return bytesBuffer.Bytes()
}