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
|
/*
* Copyright (c) 2017 Cisco and/or its affiliates.
*
* 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 io.fd.honeycomb.infra.distro.activation;
import com.google.inject.Inject;
import com.google.inject.Module;
import com.google.inject.Provider;
import io.fd.honeycomb.infra.distro.schema.ResourceLoader;
import java.util.ArrayList;
import java.util.List;
import java.util.Set;
import java.util.stream.Collectors;
import javax.annotation.Nonnull;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* Provides list of active modules for distribution
*/
public class ActiveModuleProvider implements Provider<ActiveModules>, ResourceLoader {
private static final Logger LOG = LoggerFactory.getLogger(ActiveModuleProvider.class);
@Inject
private ActivationConfig config;
@Override
public ActiveModules get() {
return new ActiveModules(loadActiveModules(
aggregateResources(config.getModulesResourcePath())));
}
/**
* Provide unique set of active modules filtered from provided resources
*/
static Set<Class<? extends Module>> loadActiveModules(@Nonnull final List<String> moduleNames) {
final ClassLoader classLoader = ActiveModuleProvider.class.getClassLoader();
LOG.info("Reading active modules configuration for distribution");
// process resources to resource modules
return moduleNames.stream()
.map(String::trim)
.filter(trimmedLine -> trimmedLine.length() != 0)
// filter out commented lines
.filter(nonEmptyLine -> !nonEmptyLine.startsWith("//"))
// filter duplicates
.distinct()
.map(validLine -> moduleNameToClass(validLine, classLoader))
// filters out classes that are not modules
.filter(ActiveModuleProvider::filterNonModules)
.collect(Collectors.toSet());
}
/**
* Aggregate all resources from provided relative path into a {@code List<String>}
*/
public List<String> aggregateResources(final String relativePath) {
// must use universal approach of loading from folder/jar
// because of memory footprint benchmark
return new ArrayList<>(loadResourceContentsOnPath(relativePath));
}
private static boolean filterNonModules(final Class<?> clazz) {
final boolean isModule = Module.class.isAssignableFrom(clazz);
if (!isModule) {
LOG.warn("Class {} is provided in modules configuration, but is not a Module and will be ignored", clazz);
}
return isModule;
}
/**
* Loads class by provided name
*/
private static Class<? extends Module> moduleNameToClass(final String name,
final ClassLoader classLoader) {
try {
LOG.debug("Loading module class {}", name);
return (Class<? extends Module>) classLoader.loadClass(name);
} catch (ClassNotFoundException e) {
LOG.error("Unable to convert {} to class, make sure you've provided sources to classpath", name);
throw new IllegalStateException(
"Unable to convert " + name + " to class, make sure you've provided sources to classpath", e);
}
}
}
|
