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
|
// Copyright 2011 The Closure Library Authors. 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.
/**
* @fileoverview Provides a convenient API for data persistence with data
* expiration and user-initiated expired key collection.
*
*/
goog.provide('goog.storage.CollectableStorage');
goog.require('goog.array');
goog.require('goog.iter');
goog.require('goog.storage.ErrorCode');
goog.require('goog.storage.ExpiringStorage');
goog.require('goog.storage.RichStorage');
/**
* Provides a storage with expiring keys and a collection method.
*
* @param {!goog.storage.mechanism.IterableMechanism} mechanism The underlying
* storage mechanism.
* @constructor
* @struct
* @extends {goog.storage.ExpiringStorage}
*/
goog.storage.CollectableStorage = function(mechanism) {
goog.storage.CollectableStorage.base(this, 'constructor', mechanism);
};
goog.inherits(goog.storage.CollectableStorage, goog.storage.ExpiringStorage);
/**
* Iterate over keys and returns those that expired.
*
* @param {goog.iter.Iterable} keys keys to iterate over.
* @param {boolean=} opt_strict Also return invalid keys.
* @return {!Array<string>} Keys of values that expired.
* @private
*/
goog.storage.CollectableStorage.prototype.getExpiredKeys_ = function(
keys, opt_strict) {
var keysToRemove = [];
goog.iter.forEach(keys, function(key) {
// Get the wrapper.
var wrapper;
try {
wrapper = goog.storage.CollectableStorage.prototype.getWrapper.call(
this, key, true);
} catch (ex) {
if (ex == goog.storage.ErrorCode.INVALID_VALUE) {
// Bad wrappers are removed in strict mode.
if (opt_strict) {
keysToRemove.push(key);
}
// Skip over bad wrappers and continue.
return;
}
// Unknown error, escalate.
throw ex;
}
if (!goog.isDef(wrapper)) {
// A value for a given key is no longer available. Clean it up.
keysToRemove.push(key);
return;
}
// Remove expired objects.
if (goog.storage.ExpiringStorage.isExpired(wrapper)) {
keysToRemove.push(key);
// Continue with the next key.
return;
}
// Objects which can't be decoded are removed in strict mode.
if (opt_strict) {
try {
goog.storage.RichStorage.Wrapper.unwrap(wrapper);
} catch (ex) {
if (ex == goog.storage.ErrorCode.INVALID_VALUE) {
keysToRemove.push(key);
// Skip over bad wrappers and continue.
return;
}
// Unknown error, escalate.
throw ex;
}
}
}, this);
return keysToRemove;
};
/**
* Cleans up the storage by removing expired keys.
*
* @param {goog.iter.Iterable} keys List of all keys.
* @param {boolean=} opt_strict Also remove invalid keys.
* @return {!Array<string>} a list of expired keys.
* @protected
*/
goog.storage.CollectableStorage.prototype.collectInternal = function(
keys, opt_strict) {
var keysToRemove = this.getExpiredKeys_(keys, opt_strict);
goog.array.forEach(keysToRemove, function(key) {
goog.storage.CollectableStorage.prototype.remove.call(this, key);
}, this);
return keysToRemove;
};
/**
* Cleans up the storage by removing expired keys.
*
* @param {boolean=} opt_strict Also remove invalid keys.
*/
goog.storage.CollectableStorage.prototype.collect = function(opt_strict) {
this.collectInternal(
/** @type {goog.storage.mechanism.IterableMechanism} */ (this.mechanism)
.__iterator__(true),
opt_strict);
};
|
