summaryrefslogtreecommitdiffstats
path: root/vendor/github.com/minio/minio-go/api-notification.go
blob: 25a283af5554104cb0b1d2898961cfa2eb0be600 (plain)
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
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
/*
 * Minio Go Library for Amazon S3 Compatible Cloud Storage (C) 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 (
	"bufio"
	"encoding/json"
	"io"
	"net/http"
	"net/url"
	"time"

	"github.com/minio/minio-go/pkg/s3utils"
)

// GetBucketNotification - get bucket notification at a given path.
func (c Client) GetBucketNotification(bucketName string) (bucketNotification BucketNotification, err error) {
	// Input validation.
	if err := s3utils.CheckValidBucketName(bucketName); err != nil {
		return BucketNotification{}, err
	}
	notification, err := c.getBucketNotification(bucketName)
	if err != nil {
		return BucketNotification{}, err
	}
	return notification, nil
}

// Request server for notification rules.
func (c Client) getBucketNotification(bucketName string) (BucketNotification, error) {
	urlValues := make(url.Values)
	urlValues.Set("notification", "")

	// Execute GET on bucket to list objects.
	resp, err := c.executeMethod("GET", requestMetadata{
		bucketName:         bucketName,
		queryValues:        urlValues,
		contentSHA256Bytes: emptySHA256,
	})

	defer closeResponse(resp)
	if err != nil {
		return BucketNotification{}, err
	}
	return processBucketNotificationResponse(bucketName, resp)

}

// processes the GetNotification http response from the server.
func processBucketNotificationResponse(bucketName string, resp *http.Response) (BucketNotification, error) {
	if resp.StatusCode != http.StatusOK {
		errResponse := httpRespToErrorResponse(resp, bucketName, "")
		return BucketNotification{}, errResponse
	}
	var bucketNotification BucketNotification
	err := xmlDecoder(resp.Body, &bucketNotification)
	if err != nil {
		return BucketNotification{}, err
	}
	return bucketNotification, nil
}

// Indentity represents the user id, this is a compliance field.
type identity struct {
	PrincipalID string `json:"principalId"`
}

// Notification event bucket metadata.
type bucketMeta struct {
	Name          string   `json:"name"`
	OwnerIdentity identity `json:"ownerIdentity"`
	ARN           string   `json:"arn"`
}

// Notification event object metadata.
type objectMeta struct {
	Key       string `json:"key"`
	Size      int64  `json:"size,omitempty"`
	ETag      string `json:"eTag,omitempty"`
	VersionID string `json:"versionId,omitempty"`
	Sequencer string `json:"sequencer"`
}

// Notification event server specific metadata.
type eventMeta struct {
	SchemaVersion   string     `json:"s3SchemaVersion"`
	ConfigurationID string     `json:"configurationId"`
	Bucket          bucketMeta `json:"bucket"`
	Object          objectMeta `json:"object"`
}

// sourceInfo represents information on the client that
// triggered the event notification.
type sourceInfo struct {
	Host      string `json:"host"`
	Port      string `json:"port"`
	UserAgent string `json:"userAgent"`
}

// NotificationEvent represents an Amazon an S3 bucket notification event.
type NotificationEvent struct {
	EventVersion      string            `json:"eventVersion"`
	EventSource       string            `json:"eventSource"`
	AwsRegion         string            `json:"awsRegion"`
	EventTime         string            `json:"eventTime"`
	EventName         string            `json:"eventName"`
	UserIdentity      identity          `json:"userIdentity"`
	RequestParameters map[string]string `json:"requestParameters"`
	ResponseElements  map[string]string `json:"responseElements"`
	S3                eventMeta         `json:"s3"`
	Source            sourceInfo        `json:"source"`
}

// NotificationInfo - represents the collection of notification events, additionally
// also reports errors if any while listening on bucket notifications.
type NotificationInfo struct {
	Records []NotificationEvent
	Err     error
}

// ListenBucketNotification - listen on bucket notifications.
func (c Client) ListenBucketNotification(bucketName, prefix, suffix string, events []string, doneCh <-chan struct{}) <-chan NotificationInfo {
	notificationInfoCh := make(chan NotificationInfo, 1)
	// Only success, start a routine to start reading line by line.
	go func(notificationInfoCh chan<- NotificationInfo) {
		defer close(notificationInfoCh)

		// Validate the bucket name.
		if err := s3utils.CheckValidBucketName(bucketName); err != nil {
			notificationInfoCh <- NotificationInfo{
				Err: err,
			}
			return
		}

		// Check ARN partition to verify if listening bucket is supported
		if s3utils.IsAmazonEndpoint(c.endpointURL) || s3utils.IsGoogleEndpoint(c.endpointURL) {
			notificationInfoCh <- NotificationInfo{
				Err: ErrAPINotSupported("Listening bucket notification is specific only to `minio` partitions"),
			}
			return
		}

		// Continuously run and listen on bucket notification.
		// Create a done channel to control 'ListObjects' go routine.
		retryDoneCh := make(chan struct{}, 1)

		// Indicate to our routine to exit cleanly upon return.
		defer close(retryDoneCh)

		// Wait on the jitter retry loop.
		for range c.newRetryTimerContinous(time.Second, time.Second*30, MaxJitter, retryDoneCh) {
			urlValues := make(url.Values)
			urlValues.Set("prefix", prefix)
			urlValues.Set("suffix", suffix)
			urlValues["events"] = events

			// Execute GET on bucket to list objects.
			resp, err := c.executeMethod("GET", requestMetadata{
				bucketName:         bucketName,
				queryValues:        urlValues,
				contentSHA256Bytes: emptySHA256,
			})
			if err != nil {
				continue
			}

			// Validate http response, upon error return quickly.
			if resp.StatusCode != http.StatusOK {
				errResponse := httpRespToErrorResponse(resp, bucketName, "")
				notificationInfoCh <- NotificationInfo{
					Err: errResponse,
				}
				return
			}

			// Initialize a new bufio scanner, to read line by line.
			bio := bufio.NewScanner(resp.Body)

			// Close the response body.
			defer resp.Body.Close()

			// Unmarshal each line, returns marshalled values.
			for bio.Scan() {
				var notificationInfo NotificationInfo
				if err = json.Unmarshal(bio.Bytes(), &notificationInfo); err != nil {
					continue
				}
				// Send notifications on channel only if there are events received.
				if len(notificationInfo.Records) > 0 {
					select {
					case notificationInfoCh <- notificationInfo:
					case <-doneCh:
						return
					}
				}
			}
			// Look for any underlying errors.
			if err = bio.Err(); err != nil {
				// For an unexpected connection drop from server, we close the body
				// and re-connect.
				if err == io.ErrUnexpectedEOF {
					resp.Body.Close()
				}
			}
		}
	}(notificationInfoCh)

	// Returns the notification info channel, for caller to start reading from.
	return notificationInfoCh
}