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
|
// Copyright Yahoo. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
package com.yahoo.container.di;
import com.google.common.collect.Sets;
import com.yahoo.config.ConfigInstance;
import com.yahoo.container.di.componentgraph.core.Keys;
import com.yahoo.container.di.config.Subscriber;
import com.yahoo.vespa.config.ConfigKey;
import java.util.Collections;
import java.util.HashSet;
import java.util.Map;
import java.util.Optional;
import java.util.Set;
import java.util.function.Function;
import java.util.logging.Level;
import java.util.logging.Logger;
import static java.util.logging.Level.FINE;
/**
* @author Tony Vaagenes
* @author gjoranv
* @author ollivir
*/
public final class ConfigRetriever {
private static final Logger log = Logger.getLogger(ConfigRetriever.class.getName());
private final Set<ConfigKey<? extends ConfigInstance>> bootstrapKeys;
private Set<ConfigKey<? extends ConfigInstance>> componentSubscriberKeys;
private final Subscriber bootstrapSubscriber;
private Subscriber componentSubscriber;
private final Function<Set<ConfigKey<? extends ConfigInstance>>, Subscriber> subscribe;
public ConfigRetriever(Set<ConfigKey<? extends ConfigInstance>> bootstrapKeys,
Function<Set<ConfigKey<? extends ConfigInstance>>, Subscriber> subscribe) {
this.bootstrapKeys = bootstrapKeys;
this.componentSubscriberKeys = new HashSet<>();
this.subscribe = subscribe;
if (bootstrapKeys.isEmpty()) {
throw new IllegalArgumentException("Bootstrap key set is empty");
}
this.bootstrapSubscriber = subscribe.apply(bootstrapKeys);
this.componentSubscriber = subscribe.apply(componentSubscriberKeys);
}
public ConfigSnapshot getConfigs(Set<ConfigKey<? extends ConfigInstance>> componentConfigKeys,
long leastGeneration, boolean isInitializing) {
// Loop until we get config.
while (true) {
Optional<ConfigSnapshot> maybeSnapshot = getConfigsOnce(componentConfigKeys, leastGeneration, isInitializing);
if (maybeSnapshot.isPresent()) {
var configSnapshot = maybeSnapshot.get();
resetComponentSubscriberIfBootstrap(configSnapshot);
return configSnapshot;
}
}
}
Optional<ConfigSnapshot> getConfigsOnce(Set<ConfigKey<? extends ConfigInstance>> componentConfigKeys,
long leastGeneration, boolean isInitializing) {
if (!Sets.intersection(componentConfigKeys, bootstrapKeys).isEmpty()) {
throw new IllegalArgumentException(
"Component config keys [" + componentConfigKeys + "] overlaps with bootstrap config keys [" + bootstrapKeys + "]");
}
log.log(FINE, () -> "getConfigsOnce: " + componentConfigKeys);
Set<ConfigKey<? extends ConfigInstance>> allKeys = new HashSet<>(componentConfigKeys);
allKeys.addAll(bootstrapKeys);
setupComponentSubscriber(allKeys);
return getConfigsOptional(leastGeneration, isInitializing);
}
private Optional<ConfigSnapshot> getConfigsOptional(long leastGeneration, boolean isInitializing) {
long newestComponentGeneration = componentSubscriber.waitNextGeneration(isInitializing);
log.log(FINE, () -> "getConfigsOptional: new component generation: " + newestComponentGeneration);
// leastGeneration is only used to ensure newer generation when the previous generation was invalidated due to an exception
if (newestComponentGeneration < leastGeneration) {
return Optional.empty();
} else if (bootstrapSubscriber.generation() < newestComponentGeneration) {
long newestBootstrapGeneration = bootstrapSubscriber.waitNextGeneration(isInitializing);
log.log(FINE, () -> "getConfigsOptional: new bootstrap generation: " + bootstrapSubscriber.generation());
Optional<ConfigSnapshot> bootstrapConfig = bootstrapConfigIfChanged();
if (bootstrapConfig.isPresent()) {
return bootstrapConfig;
} else {
if (newestBootstrapGeneration == newestComponentGeneration) {
log.log(FINE, () -> "Got new components configs with unchanged bootstrap configs.");
return componentsConfigIfChanged();
} else {
// This should not be a normal case, and hence a warning to allow investigation.
log.warning("Did not get same generation for bootstrap (" + newestBootstrapGeneration +
") and components configs (" + newestComponentGeneration + ").");
return Optional.empty();
}
}
} else {
// bootstrapGen==componentGen (happens only when a new component subscriber returns first config after bootstrap)
return componentsConfigIfChanged();
}
}
private Optional<ConfigSnapshot> bootstrapConfigIfChanged() {
return configIfChanged(bootstrapSubscriber, BootstrapConfigs::new);
}
private Optional<ConfigSnapshot> componentsConfigIfChanged() {
return configIfChanged(componentSubscriber, ComponentsConfigs::new);
}
private Optional<ConfigSnapshot> configIfChanged(Subscriber subscriber,
Function<Map<ConfigKey<? extends ConfigInstance>, ConfigInstance>, ConfigSnapshot> constructor) {
if (subscriber.configChanged()) {
return Optional.of(constructor.apply(Keys.covariantCopy(subscriber.config())));
} else {
return Optional.empty();
}
}
private void resetComponentSubscriberIfBootstrap(ConfigSnapshot snapshot) {
if (snapshot instanceof BootstrapConfigs) {
setupComponentSubscriber(Collections.emptySet());
}
}
private void setupComponentSubscriber(Set<ConfigKey<? extends ConfigInstance>> keys) {
if (! componentSubscriberKeys.equals(keys)) {
componentSubscriber.close();
componentSubscriberKeys = keys;
try {
log.log(FINE, () -> "Setting up new component subscriber for keys: " + keys);
componentSubscriber = subscribe.apply(keys);
} catch (Throwable e) {
log.log(Level.WARNING, "Failed setting up subscriptions for component configs: " + e.getMessage());
log.log(Level.WARNING, "Config keys: " + keys);
throw e;
}
}
}
public void shutdown() {
bootstrapSubscriber.close();
componentSubscriber.close();
}
//TODO: check if these are really needed
public long getBootstrapGeneration() {
return bootstrapSubscriber.generation();
}
public long getComponentsGeneration() {
return componentSubscriber.generation();
}
public static class ConfigSnapshot {
private final Map<ConfigKey<? extends ConfigInstance>, ConfigInstance> configs;
ConfigSnapshot(Map<ConfigKey<? extends ConfigInstance>, ConfigInstance> configs) {
this.configs = configs;
}
public Map<ConfigKey<? extends ConfigInstance>, ConfigInstance> configs() {
return configs;
}
public int size() {
return configs.size();
}
}
public static class BootstrapConfigs extends ConfigSnapshot {
BootstrapConfigs(Map<ConfigKey<? extends ConfigInstance>, ConfigInstance> configs) {
super(configs);
}
}
public static class ComponentsConfigs extends ConfigSnapshot {
ComponentsConfigs(Map<ConfigKey<? extends ConfigInstance>, ConfigInstance> configs) {
super(configs);
}
}
}
|
