Restructure minio api, move signature checks from utils to Api.

pkg/api/headers.go

@@ -0,0 +1,98 @@
+/*
+ * Mini Object 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"
+	"encoding/json"
+	"encoding/xml"
+	"net/http"
+	"strconv"
+	"time"
+
+	mstorage "github.com/minio-io/minio/pkg/storage"
+)
+
+// No encoder interface exists, so we create one.
+type encoder interface {
+	Encode(v interface{}) error
+}
+
+//// helpers
+
+// Write http common headers
+func writeCommonHeaders(w http.ResponseWriter, acceptsType string) {
+	w.Header().Set("Server", "Minio")
+	w.Header().Set("Accept-Ranges", "bytes")
+	w.Header().Set("Content-Type", acceptsType)
+}
+
+// Write error response headers
+func writeErrorResponse(w http.ResponseWriter, response interface{}, acceptsType contentType) []byte {
+	var bytesBuffer bytes.Buffer
+	var encoder encoder
+	// write common headers
+	writeCommonHeaders(w, getContentString(acceptsType))
+	switch acceptsType {
+	case xmlType:
+		encoder = xml.NewEncoder(&bytesBuffer)
+	case jsonType:
+		encoder = json.NewEncoder(&bytesBuffer)
+	}
+	encoder.Encode(response)
+	return bytesBuffer.Bytes()
+}
+
+// Write object header
+func writeObjectHeaders(w http.ResponseWriter, metadata mstorage.ObjectMetadata) {
+	lastModified := metadata.Created.Format(time.RFC1123)
+	// common headers
+	writeCommonHeaders(w, metadata.ContentType)
+	w.Header().Set("ETag", metadata.Md5)
+	w.Header().Set("Last-Modified", lastModified)
+	w.Header().Set("Content-Length", strconv.FormatInt(metadata.Size, 10))
+	w.Header().Set("Connection", "close")
+}
+
+// Write range object header
+func writeRangeObjectHeaders(w http.ResponseWriter, metadata mstorage.ObjectMetadata, ra string) {
+	lastModified := metadata.Created.Format(time.RFC1123)
+	// common headers
+	writeCommonHeaders(w, metadata.ContentType)
+	w.Header().Set("ETag", metadata.Md5)
+	w.Header().Set("Last-Modified", lastModified)
+	w.Header().Set("Content-Range", ra)
+	w.Header().Set("Content-Length", strconv.FormatInt(metadata.Size, 10))
+}
+
+// Write object header and response
+func writeObjectHeadersAndResponse(w http.ResponseWriter, response interface{}, acceptsType contentType) []byte {
+	var bytesBuffer bytes.Buffer
+	var encoder encoder
+	// common headers
+	writeCommonHeaders(w, getContentString(acceptsType))
+	switch acceptsType {
+	case xmlType:
+		encoder = xml.NewEncoder(&bytesBuffer)
+	case jsonType:
+		encoder = json.NewEncoder(&bytesBuffer)
+	}
+
+	w.Header().Set("Connection", "close")
+	encoder.Encode(response)
+	return bytesBuffer.Bytes()
+}