1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
|
/*
* Minio Go Library for Amazon S3 Compatible Cloud Storage (C) 2015, 2016 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 minio
import (
"net/http"
"strconv"
"strings"
"time"
"github.com/minio/minio-go/pkg/s3utils"
)
// BucketExists verify if bucket exists and you have permission to access it.
func (c Client) BucketExists(bucketName string) (bool, error) {
// Input validation.
if err := isValidBucketName(bucketName); err != nil {
return false, err
}
// Execute HEAD on bucketName.
resp, err := c.executeMethod("HEAD", requestMetadata{
bucketName: bucketName,
contentSHA256Bytes: emptySHA256,
})
defer closeResponse(resp)
if err != nil {
if ToErrorResponse(err).Code == "NoSuchBucket" {
return false, nil
}
return false, err
}
if resp != nil {
if resp.StatusCode != http.StatusOK {
return false, httpRespToErrorResponse(resp, bucketName, "")
}
}
return true, nil
}
// List of header keys to be filtered, usually
// from all S3 API http responses.
var defaultFilterKeys = []string{
"Transfer-Encoding",
"Accept-Ranges",
"Date",
"Server",
"Vary",
"x-amz-request-id",
"x-amz-id-2",
// Add new headers to be ignored.
}
// Extract only necessary metadata header key/values by
// filtering them out with a list of custom header keys.
func extractObjMetadata(header http.Header) http.Header {
filterKeys := append([]string{
"ETag",
"Content-Length",
"Last-Modified",
"Content-Type",
}, defaultFilterKeys...)
return filterHeader(header, filterKeys)
}
// StatObject verifies if object exists and you have permission to access.
func (c Client) StatObject(bucketName, objectName string) (ObjectInfo, error) {
// Input validation.
if err := isValidBucketName(bucketName); err != nil {
return ObjectInfo{}, err
}
if err := isValidObjectName(objectName); err != nil {
return ObjectInfo{}, err
}
reqHeaders := NewHeadReqHeaders()
return c.statObject(bucketName, objectName, reqHeaders)
}
// Lower level API for statObject supporting pre-conditions and range headers.
func (c Client) statObject(bucketName, objectName string, reqHeaders RequestHeaders) (ObjectInfo, error) {
// Input validation.
if err := isValidBucketName(bucketName); err != nil {
return ObjectInfo{}, err
}
if err := isValidObjectName(objectName); err != nil {
return ObjectInfo{}, err
}
customHeader := make(http.Header)
for k, v := range reqHeaders.Header {
customHeader[k] = v
}
// Execute HEAD on objectName.
resp, err := c.executeMethod("HEAD", requestMetadata{
bucketName: bucketName,
objectName: objectName,
contentSHA256Bytes: emptySHA256,
customHeader: customHeader,
})
defer closeResponse(resp)
if err != nil {
return ObjectInfo{}, err
}
if resp != nil {
if resp.StatusCode != http.StatusOK {
return ObjectInfo{}, httpRespToErrorResponse(resp, bucketName, objectName)
}
}
// Trim off the odd double quotes from ETag in the beginning and end.
md5sum := strings.TrimPrefix(resp.Header.Get("ETag"), "\"")
md5sum = strings.TrimSuffix(md5sum, "\"")
// Content-Length is not valid for Google Cloud Storage, do not verify.
var size int64 = -1
if !s3utils.IsGoogleEndpoint(c.endpointURL) {
// Parse content length.
size, err = strconv.ParseInt(resp.Header.Get("Content-Length"), 10, 64)
if err != nil {
return ObjectInfo{}, ErrorResponse{
Code: "InternalError",
Message: "Content-Length is invalid. " + reportIssue,
BucketName: bucketName,
Key: objectName,
RequestID: resp.Header.Get("x-amz-request-id"),
HostID: resp.Header.Get("x-amz-id-2"),
Region: resp.Header.Get("x-amz-bucket-region"),
}
}
}
// Parse Last-Modified has http time format.
date, err := time.Parse(http.TimeFormat, resp.Header.Get("Last-Modified"))
if err != nil {
return ObjectInfo{}, ErrorResponse{
Code: "InternalError",
Message: "Last-Modified time format is invalid. " + reportIssue,
BucketName: bucketName,
Key: objectName,
RequestID: resp.Header.Get("x-amz-request-id"),
HostID: resp.Header.Get("x-amz-id-2"),
Region: resp.Header.Get("x-amz-bucket-region"),
}
}
// Fetch content type if any present.
contentType := strings.TrimSpace(resp.Header.Get("Content-Type"))
if contentType == "" {
contentType = "application/octet-stream"
}
// Extract only the relevant header keys describing the object.
// following function filters out a list of standard set of keys
// which are not part of object metadata.
metadata := extractObjMetadata(resp.Header)
// Save object metadata info.
return ObjectInfo{
ETag: md5sum,
Key: objectName,
Size: size,
LastModified: date,
ContentType: contentType,
Metadata: metadata,
}, nil
}
|
