minio/cmd/gateway-b2-anonymous.go

135 lines
4.5 KiB
Go

/*
* Minio Cloud Storage, (C) 2017 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 cmd
import (
"fmt"
"io"
"net/http"
"net/url"
"strconv"
"strings"
"time"
"github.com/minio/minio/pkg/errors"
)
// mkRange converts offset, size into Range header equivalent.
func mkRange(offset, size int64) string {
if offset == 0 && size == 0 {
return ""
}
if size == 0 {
return fmt.Sprintf("%s%d-", byteRangePrefix, offset)
}
return fmt.Sprintf("%s%d-%d", byteRangePrefix, offset, offset+size-1)
}
// AnonGetObject - performs a plain http GET request on a public resource,
// fails if the resource is not public.
func (l *b2Objects) AnonGetObject(bucket string, object string, startOffset int64, length int64, writer io.Writer) error {
uri := fmt.Sprintf("%s/file/%s/%s", l.b2Client.DownloadURI, bucket, object)
req, err := http.NewRequest("GET", uri, nil)
if err != nil {
return b2ToObjectError(errors.Trace(err), bucket, object)
}
rng := mkRange(startOffset, length)
if rng != "" {
req.Header.Set("Range", rng)
}
resp, err := l.anonClient.Do(req)
if err != nil {
return b2ToObjectError(errors.Trace(err), bucket, object)
}
defer resp.Body.Close()
if resp.StatusCode != http.StatusOK {
return b2ToObjectError(errors.Trace(fmt.Errorf(resp.Status)), bucket, object)
}
_, err = io.Copy(writer, resp.Body)
return b2ToObjectError(errors.Trace(err), bucket, object)
}
// Converts http Header into ObjectInfo. This function looks for all the
// standard Backblaze B2 headers to convert into ObjectInfo.
//
// Content-Length is converted to Size.
// X-Bz-Upload-Timestamp is converted to ModTime.
// X-Bz-Info-<header>:<value> is converted to <header>:<value>
// Content-Type is converted to ContentType.
// X-Bz-Content-Sha1 is converted to ETag.
func headerToObjectInfo(bucket, object string, header http.Header) (objInfo ObjectInfo, err error) {
clen, err := strconv.ParseInt(header.Get("Content-Length"), 10, 64)
if err != nil {
return objInfo, b2ToObjectError(errors.Trace(err), bucket, object)
}
// Converting upload timestamp in milliseconds to a time.Time value for ObjectInfo.ModTime.
timeStamp, err := strconv.ParseInt(header.Get("X-Bz-Upload-Timestamp"), 10, 64)
if err != nil {
return objInfo, b2ToObjectError(errors.Trace(err), bucket, object)
}
// Populate user metadata by looking for all the X-Bz-Info-<name>
// HTTP headers, ignore other headers since they have their own
// designated meaning, for more details refer B2 API documentation.
userMetadata := make(map[string]string)
for key := range header {
if strings.HasPrefix(key, "X-Bz-Info-") {
var name string
name, err = url.QueryUnescape(strings.TrimPrefix(key, "X-Bz-Info-"))
if err != nil {
return objInfo, b2ToObjectError(errors.Trace(err), bucket, object)
}
var val string
val, err = url.QueryUnescape(header.Get(key))
if err != nil {
return objInfo, b2ToObjectError(errors.Trace(err), bucket, object)
}
userMetadata[name] = val
}
}
return ObjectInfo{
Bucket: bucket,
Name: object,
ContentType: header.Get("Content-Type"),
ModTime: time.Unix(0, 0).Add(time.Duration(timeStamp) * time.Millisecond),
Size: clen,
ETag: header.Get("X-Bz-File-Id"),
UserDefined: userMetadata,
}, nil
}
// AnonGetObjectInfo - performs a plain http HEAD request on a public resource,
// fails if the resource is not public.
func (l *b2Objects) AnonGetObjectInfo(bucket string, object string) (objInfo ObjectInfo, err error) {
uri := fmt.Sprintf("%s/file/%s/%s", l.b2Client.DownloadURI, bucket, object)
req, err := http.NewRequest("HEAD", uri, nil)
if err != nil {
return objInfo, b2ToObjectError(errors.Trace(err), bucket, object)
}
resp, err := l.anonClient.Do(req)
if err != nil {
return objInfo, b2ToObjectError(errors.Trace(err), bucket, object)
}
defer resp.Body.Close()
if resp.StatusCode != http.StatusOK {
return objInfo, b2ToObjectError(errors.Trace(fmt.Errorf(resp.Status)), bucket, object)
}
return headerToObjectInfo(bucket, object, resp.Header)
}