/
SignalTransformer.java
72 lines (59 loc) · 2.63 KB
/
SignalTransformer.java
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
/*
* Copyright (c) 2022 Contributors to the Eclipse Foundation
*
* See the NOTICE file(s) distributed with this work for additional
* information regarding copyright ownership.
*
* This program and the accompanying materials are made available under the
* terms of the Eclipse Public License 2.0 which is available at
* http://www.eclipse.org/legal/epl-2.0
*
* SPDX-License-Identifier: EPL-2.0
*/
package org.eclipse.ditto.edge.service.dispatching;
import static org.eclipse.ditto.base.model.common.ConditionChecker.checkNotNull;
import java.util.concurrent.CompletionStage;
import java.util.function.Function;
import org.eclipse.ditto.base.model.signals.Signal;
import org.eclipse.ditto.base.service.DittoExtensionIds;
import org.eclipse.ditto.base.service.DittoExtensionPoint;
import com.typesafe.config.Config;
import akka.actor.ActorSystem;
/**
* Extension which transforms a received {@link Signal} (at the "edge") to a CompletionStage of a transformed Signal,
* e.g. in order to enhance the Signal.
*/
@FunctionalInterface
public interface SignalTransformer extends Function<Signal<?>, CompletionStage<Signal<?>>>, DittoExtensionPoint {
/**
* Loads the implementation of {@code SignalTransformer} which is configured for the
* {@code ActorSystem}.
*
* @param actorSystem the actorSystem in which the {@code SignalTransformer} should be loaded.
* @param config the configuration of this extension.
* @return the {@code SignalTransformer} implementation.
* @throws NullPointerException if {@code actorSystem} is {@code null}.
*/
static SignalTransformer get(final ActorSystem actorSystem, final Config config) {
checkNotNull(actorSystem, "actorSystem");
checkNotNull(config, "config");
final var extensionIdConfig = ExtensionId.computeConfig(config);
return DittoExtensionIds.get(actorSystem)
.computeIfAbsent(extensionIdConfig, ExtensionId::new)
.get(actorSystem);
}
final class ExtensionId extends DittoExtensionPoint.ExtensionId<SignalTransformer> {
private static final String CONFIG_KEY = "signal-transformer";
private static final String CONFIG_PATH = "ditto.extensions." + CONFIG_KEY;
private ExtensionId(final ExtensionIdConfig<SignalTransformer> extensionIdConfig) {
super(extensionIdConfig);
}
static ExtensionIdConfig<SignalTransformer> computeConfig(final Config config) {
return ExtensionIdConfig.of(SignalTransformer.class, config, CONFIG_KEY);
}
@Override
protected String getConfigPath() {
return CONFIG_PATH;
}
}
}