org.springframework.boot.context.properties.source.SpringConfigurationPropertySource Maven / Gradle / Ivy
/*
* Copyright 2012-2018 the original author or authors.
*
* 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
*
* https://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 org.springframework.boot.context.properties.source;
import java.util.Map;
import java.util.Random;
import java.util.function.Function;
import org.springframework.boot.origin.Origin;
import org.springframework.boot.origin.PropertySourceOrigin;
import org.springframework.core.env.EnumerablePropertySource;
import org.springframework.core.env.PropertySource;
import org.springframework.core.env.StandardEnvironment;
import org.springframework.core.env.SystemEnvironmentPropertySource;
import org.springframework.util.Assert;
import org.springframework.util.ObjectUtils;
/**
* {@link ConfigurationPropertySource} backed by a non-enumerable Spring
* {@link PropertySource} or a restricted {@link EnumerablePropertySource} implementation
* (such as a security restricted {@code systemEnvironment} source). A
* {@link PropertySource} is adapted with the help of a {@link PropertyMapper} which
* provides the mapping rules for individual properties.
*
* Each {@link ConfigurationPropertySource#getConfigurationProperty
* getConfigurationProperty} call attempts to
* {@link PropertyMapper#map(ConfigurationPropertyName) map} the
* {@link ConfigurationPropertyName} to one or more {@code String} based names. This
* allows fast property resolution for well formed property sources.
*
* When possible the {@link SpringIterableConfigurationPropertySource} will be used in
* preference to this implementation since it supports full "relaxed" style resolution.
*
* @author Phillip Webb
* @author Madhura Bhave
* @see #from(PropertySource)
* @see PropertyMapper
* @see SpringIterableConfigurationPropertySource
*/
class SpringConfigurationPropertySource implements ConfigurationPropertySource {
private static final ConfigurationPropertyName RANDOM = ConfigurationPropertyName
.of("random");
private final PropertySource propertySource;
private final PropertyMapper mapper;
private final Function containsDescendantOf;
/**
* Create a new {@link SpringConfigurationPropertySource} implementation.
* @param propertySource the source property source
* @param mapper the property mapper
* @param containsDescendantOf function used to implement
* {@link #containsDescendantOf(ConfigurationPropertyName)} (may be {@code null})
*/
SpringConfigurationPropertySource(PropertySource propertySource,
PropertyMapper mapper,
Function containsDescendantOf) {
Assert.notNull(propertySource, "PropertySource must not be null");
Assert.notNull(mapper, "Mapper must not be null");
this.propertySource = propertySource;
this.mapper = (mapper instanceof DelegatingPropertyMapper) ? mapper
: new DelegatingPropertyMapper(mapper);
this.containsDescendantOf = (containsDescendantOf != null) ? containsDescendantOf
: (n) -> ConfigurationPropertyState.UNKNOWN;
}
@Override
public ConfigurationProperty getConfigurationProperty(
ConfigurationPropertyName name) {
PropertyMapping[] mappings = getMapper().map(name);
return find(mappings, name);
}
@Override
public ConfigurationPropertyState containsDescendantOf(
ConfigurationPropertyName name) {
return this.containsDescendantOf.apply(name);
}
@Override
public Object getUnderlyingSource() {
return this.propertySource;
}
protected final ConfigurationProperty find(PropertyMapping[] mappings,
ConfigurationPropertyName name) {
for (PropertyMapping candidate : mappings) {
if (candidate.isApplicable(name)) {
ConfigurationProperty result = find(candidate);
if (result != null) {
return result;
}
}
}
return null;
}
private ConfigurationProperty find(PropertyMapping mapping) {
String propertySourceName = mapping.getPropertySourceName();
Object value = getPropertySource().getProperty(propertySourceName);
if (value == null) {
return null;
}
ConfigurationPropertyName configurationPropertyName = mapping
.getConfigurationPropertyName();
Origin origin = PropertySourceOrigin.get(this.propertySource, propertySourceName);
return ConfigurationProperty.of(configurationPropertyName, value, origin);
}
protected PropertySource getPropertySource() {
return this.propertySource;
}
protected final PropertyMapper getMapper() {
return this.mapper;
}
@Override
public String toString() {
return this.propertySource.toString();
}
/**
* Create a new {@link SpringConfigurationPropertySource} for the specified
* {@link PropertySource}.
* @param source the source Spring {@link PropertySource}
* @return a {@link SpringConfigurationPropertySource} or
* {@link SpringIterableConfigurationPropertySource} instance
*/
public static SpringConfigurationPropertySource from(PropertySource source) {
Assert.notNull(source, "Source must not be null");
PropertyMapper mapper = getPropertyMapper(source);
if (isFullEnumerable(source)) {
return new SpringIterableConfigurationPropertySource(
(EnumerablePropertySource) source, mapper);
}
return new SpringConfigurationPropertySource(source, mapper,
getContainsDescendantOfForSource(source));
}
private static PropertyMapper getPropertyMapper(PropertySource source) {
if (source instanceof SystemEnvironmentPropertySource
&& hasSystemEnvironmentName(source)) {
return new DelegatingPropertyMapper(SystemEnvironmentPropertyMapper.INSTANCE,
DefaultPropertyMapper.INSTANCE);
}
return new DelegatingPropertyMapper(DefaultPropertyMapper.INSTANCE);
}
private static boolean hasSystemEnvironmentName(PropertySource source) {
String name = source.getName();
return StandardEnvironment.SYSTEM_ENVIRONMENT_PROPERTY_SOURCE_NAME.equals(name)
|| name.endsWith("-"
+ StandardEnvironment.SYSTEM_ENVIRONMENT_PROPERTY_SOURCE_NAME);
}
private static boolean isFullEnumerable(PropertySource source) {
PropertySource rootSource = getRootSource(source);
if (rootSource.getSource() instanceof Map) {
// Check we're not security restricted
try {
((Map) rootSource.getSource()).size();
}
catch (UnsupportedOperationException ex) {
return false;
}
}
return (source instanceof EnumerablePropertySource);
}
private static PropertySource getRootSource(PropertySource source) {
while (source.getSource() != null
&& source.getSource() instanceof PropertySource) {
source = (PropertySource) source.getSource();
}
return source;
}
private static Function getContainsDescendantOfForSource(
PropertySource source) {
if (source.getSource() instanceof Random) {
return SpringConfigurationPropertySource::containsDescendantOfForRandom;
}
return null;
}
private static ConfigurationPropertyState containsDescendantOfForRandom(
ConfigurationPropertyName name) {
if (name.isAncestorOf(RANDOM) || name.equals(RANDOM)) {
return ConfigurationPropertyState.PRESENT;
}
return ConfigurationPropertyState.ABSENT;
}
/**
* {@link PropertyMapper} that delegates to other {@link PropertyMapper}s and also
* swallows exceptions when the mapping fails.
*/
private static class DelegatingPropertyMapper implements PropertyMapper {
private static final PropertyMapping[] NONE = {};
private final PropertyMapper first;
private final PropertyMapper second;
DelegatingPropertyMapper(PropertyMapper first) {
this(first, null);
}
DelegatingPropertyMapper(PropertyMapper first, PropertyMapper second) {
this.first = first;
this.second = second;
}
@Override
public PropertyMapping[] map(
ConfigurationPropertyName configurationPropertyName) {
PropertyMapping[] first = map(this.first, configurationPropertyName);
PropertyMapping[] second = map(this.second, configurationPropertyName);
return merge(first, second);
}
private PropertyMapping[] map(PropertyMapper mapper,
ConfigurationPropertyName configurationPropertyName) {
try {
return (mapper != null) ? mapper.map(configurationPropertyName) : NONE;
}
catch (Exception ex) {
return NONE;
}
}
@Override
public PropertyMapping[] map(String propertySourceName) {
PropertyMapping[] first = map(this.first, propertySourceName);
PropertyMapping[] second = map(this.second, propertySourceName);
return merge(first, second);
}
private PropertyMapping[] map(PropertyMapper mapper, String propertySourceName) {
try {
return (mapper != null) ? mapper.map(propertySourceName) : NONE;
}
catch (Exception ex) {
return NONE;
}
}
private PropertyMapping[] merge(PropertyMapping[] first,
PropertyMapping[] second) {
if (ObjectUtils.isEmpty(second)) {
return first;
}
if (ObjectUtils.isEmpty(first)) {
return second;
}
PropertyMapping[] merged = new PropertyMapping[first.length + second.length];
System.arraycopy(first, 0, merged, 0, first.length);
System.arraycopy(second, 0, merged, first.length, second.length);
return merged;
}
}
}