forked from minio/minio
-
Notifications
You must be signed in to change notification settings - Fork 0
/
queuestore.go
190 lines (155 loc) · 3.8 KB
/
queuestore.go
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
/*
* MinIO Cloud Storage, (C) 2019 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 target
import (
"encoding/json"
"io/ioutil"
"os"
"path/filepath"
"sort"
"sync"
"github.com/minio/minio/pkg/event"
"github.com/minio/minio/pkg/sys"
)
const (
maxLimit = 10000 // Max store limit.
eventExt = ".event"
)
// QueueStore - Filestore for persisting events.
type QueueStore struct {
sync.RWMutex
directory string
eC uint64
limit uint64
}
// NewQueueStore - Creates an instance for QueueStore.
func NewQueueStore(directory string, limit uint64) *QueueStore {
if limit == 0 {
limit = maxLimit
currRlimit, _, err := sys.GetMaxOpenFileLimit()
if err == nil {
if currRlimit > limit {
limit = currRlimit
}
}
}
queueStore := &QueueStore{
directory: directory,
limit: limit,
}
return queueStore
}
// Open - Creates the directory if not present.
func (store *QueueStore) Open() error {
store.Lock()
defer store.Unlock()
if terr := os.MkdirAll(store.directory, os.FileMode(0770)); terr != nil {
return terr
}
eCount := uint64(len(store.list()))
if eCount >= store.limit {
return errLimitExceeded
}
store.eC = eCount
return nil
}
// write - writes event to the directory.
func (store *QueueStore) write(directory string, key string, e event.Event) error {
// Marshalls the event.
eventData, err := json.Marshal(e)
if err != nil {
return err
}
path := filepath.Join(store.directory, key+eventExt)
if err := ioutil.WriteFile(path, eventData, os.FileMode(0770)); err != nil {
return err
}
// Increment the event count.
store.eC++
return nil
}
// Put - puts a event to the store.
func (store *QueueStore) Put(e event.Event) error {
store.Lock()
defer store.Unlock()
if store.eC >= store.limit {
return errLimitExceeded
}
key, kErr := getNewUUID()
if kErr != nil {
return kErr
}
return store.write(store.directory, key, e)
}
// Get - gets a event from the store.
func (store *QueueStore) Get(key string) (event.Event, error) {
store.RLock()
defer store.RUnlock()
var event event.Event
filepath := filepath.Join(store.directory, key+eventExt)
eventData, rerr := ioutil.ReadFile(filepath)
if rerr != nil {
store.del(key)
return event, rerr
}
if len(eventData) == 0 {
store.del(key)
}
uerr := json.Unmarshal(eventData, &event)
if uerr != nil {
store.del(key)
return event, uerr
}
return event, nil
}
// Del - Deletes an entry from the store.
func (store *QueueStore) Del(key string) error {
store.Lock()
defer store.Unlock()
return store.del(key)
}
// lockless call
func (store *QueueStore) del(key string) error {
p := filepath.Join(store.directory, key+eventExt)
rerr := os.Remove(p)
if rerr != nil {
return rerr
}
// Decrement the event count.
store.eC--
return nil
}
// List - lists all files from the directory.
func (store *QueueStore) List() []string {
store.RLock()
defer store.RUnlock()
return store.list()
}
// lockless call.
func (store *QueueStore) list() []string {
var names []string
storeDir, _ := os.Open(store.directory)
files, _ := storeDir.Readdir(-1)
// Sort the dentries.
sort.Slice(files, func(i, j int) bool {
return files[i].ModTime().Unix() < files[j].ModTime().Unix()
})
for _, file := range files {
names = append(names, file.Name())
}
_ = storeDir.Close()
return names
}