objectget.go

// Copyright (c) 2018 Huawei Technologies Co., Ltd. All Rights Reserved.
//
// 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 s3

import (
	"bytes"
	"net/http"
	"strconv"
	"strings"

	"github.com/opensds/multi-cloud/api/pkg/s3/datastore"

	"github.com/emicklei/go-restful"
	"github.com/micro/go-log"

	. "github.com/opensds/multi-cloud/s3/pkg/exception"
	s3 "github.com/opensds/multi-cloud/s3/proto"
	"golang.org/x/net/context"
)

//ObjectGet -
func (s *APIService) ObjectGet(request *restful.Request, response *restful.Response) {
	bucketName := request.PathParameter("bucketName")
	objectKey := request.PathParameter("objectKey")
	rangestr := request.HeaderParameter("Range")
	log.Logf("%v\n", rangestr)
	ctx := context.WithValue(request.Request.Context(), "operation", "download")
	start := 0
	end := 0
	if rangestr != "" {
		index := strings.Index(rangestr, "-")
		startstr := string([]rune(rangestr)[6:index])
		endstr := string([]rune(rangestr)[index+1:])
		start, _ = strconv.Atoi(startstr)
		end, _ = strconv.Atoi(endstr)
	}
	log.Logf("Received request for create bucket: %s", bucketName)
	object := s3.Object{}
	objectInput := s3.GetObjectInput{Bucket: bucketName, Key: objectKey}
	log.Logf("enter the s3Client download method")
	objectMD, _ := s.s3Client.GetObject(ctx, &objectInput)
	log.Logf("out the s3Client download method")
	var backendname string
	if objectMD != nil {
		object.Size = objectMD.Size
		backendname = objectMD.Backend
	} else {
		log.Logf("No such object")
		response.WriteError(http.StatusInternalServerError, NoSuchObject.Error())
		return
	}

	object.ObjectKey = objectKey
	object.BucketName = bucketName
	var client datastore.DataStoreAdapter
	if backendname != "" {
		client = getBackendByName(s, backendname)
	} else {
		client = getBackendClient(s, bucketName)
	}
	if client == nil {
		response.WriteError(http.StatusInternalServerError, NoSuchBackend.Error())
		return
	}
	log.Logf("enter the download method")
	body, s3err := client.GET(&object, ctx, int64(start), int64(end))
	log.Logf("out  the download method")
	if s3err != NoError {
		response.WriteError(http.StatusInternalServerError, s3err.Error())
		return
	}
	buf := new(bytes.Buffer)
	buf.ReadFrom(body)
	response.Write(buf.Bytes())
}