blob: 3dd13b7e601c51af0b965c788b297c08cd6a1a52 (
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
|
/*-
* ============LICENSE_START=======================================================
* ONAP : APPC
* ================================================================================
* Copyright (C) 2017-2018 AT&T Intellectual Property. All rights reserved.
* ================================================================================
* Copyright (C) 2017 Amdocs
* =============================================================================
* 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.
*
* ============LICENSE_END=========================================================
*/
package org.onap.appc.workflow.impl;
import java.util.concurrent.locks.ReentrantLock;
import org.onap.appc.rankingframework.RankedAttributesContext;
import org.onap.appc.rankingframework.RankedAttributesResolver;
import com.att.eelf.configuration.EELFLogger;
import com.att.eelf.configuration.EELFManager;
class WorkflowResolver {
private final EELFLogger logger = EELFManager.getInstance().getLogger(WorkFlowManagerImpl.class);
private long interval;
private volatile long lastUpdate = 0L;
private volatile boolean isUpdateInProgress = false;
private volatile RankedAttributesResolver<WorkflowKey> dgResolver;
private final ReentrantLock INIT_LOCK = new ReentrantLock();
WorkflowResolver(int interval) {
this.interval = interval * 1000l;
}
private RankedAttributesResolver<WorkflowKey> createResolver() {
WorkflowResolverDataReader reader = new WorkflowResolverDataReader();
return reader.read();
}
private boolean isExpired() {
return (System.currentTimeMillis() - lastUpdate) > interval;
}
private RankedAttributesResolver<WorkflowKey> resolver() {
/*
* In general case, the method implementation is non-blocking. The first
* thread that identifies data expiration will be used to refresh it. In
* meanwhile, any other thread will get the old instance without waiting
* for the updated one. The only exception is the very first time when
* previous instance doesn't exist - in such a cases all the threads
* will be waiting on INIT_LOCK while one of them initializes the
* resolver instance. NOTE: The initialization is intentionally
* implemented in lazy manner to make sure the bundle is initialized
* properly on startup regardless whether or not the data is correct.
* Afterwards, the resolver may be instantiated as many times as needed.
*/
try {
if (dgResolver == null) {
INIT_LOCK.lock();
if (dgResolver != null) {
INIT_LOCK.unlock();
}
}
if (!isUpdateInProgress && isExpired()) {
boolean doUpgrade = false;
synchronized (this) {
if (!isUpdateInProgress) {
isUpdateInProgress = true;
doUpgrade = true;
}
}
if (doUpgrade) {
logger.info("DG resolver configuration data has expired - initiating refresh");
try {
dgResolver = createResolver();
lastUpdate = System.currentTimeMillis();
logger.info("DG resolver configuration data has been refreshed successfully");
} finally {
isUpdateInProgress = false;
}
}
}
} finally {
if (INIT_LOCK.isHeldByCurrentThread()) {
INIT_LOCK.unlock();
}
}
return dgResolver;
}
WorkflowKey resolve(final String action, final String vnfType, final String vnfVersion,final String apiVersion) {
RankedAttributesContext context = new RankedAttributesContext() {
@Override
public Object getAttributeValue(String name) {
switch (name) {
case "action":
return action;
case "api_version":
return apiVersion;
case "vnf_type":
return vnfType;
case "vnf_version":
return vnfVersion;
default:
throw new IllegalStateException(name);
}
}
};
return resolver().resolve(context);
}
}
|
