Spring/spring-framework
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

Introduce ConfigurableEnvironment#merge

Browse Source 
Prior to this change, AbstractApplicationContext#setParent replaced the
child context's Environment with the parent's Environment if available.
This has the negative effect of potentially changing the type of the
child context's Environment, and in any case causes property sources
added directly against the child environment to be ignored. This
situation could easily occur if a WebApplicationContext child had a
non-web ApplicationContext set as its parent. In this case the parent
Environment type would (likely) be StandardEnvironment, while the child
Environment type would (likely) be StandardServletEnvironment. By
directly inheriting the parent environment, critical property sources
such as ServletContextPropertySource are lost entirely.

This commit introduces the concept of merging an environment through
the new ConfigurableEnvironment#merge method. Instead of replacing the
child's environment with the parent's,
AbstractApplicationContext#setParent now merges property sources as
well as active and default profile names from the parent into the
child. In this way, distinct environment objects are maintained with
specific types and property sources preserved. See #merge Javadoc for
additional details.

Issue: SPR-9446
Backport-Issue: SPR-9444, SPR-9439
Backport-Commit: 9fcfd7e827
This commit is contained in:
Chris Beams
2012-06-27 17:01:44 +02:00
parent c25a1bcb60
commit 20f87ab98d
5 changed files with 126 additions and 49 deletions
Download Patch File Download Diff File Expand all files Collapse all files

20
org.springframework.core/src/main/java/org/springframework/core/env/AbstractEnvironment.java vendored
View File

@@ -41,9 +41,9 @@ import static org.springframework.util.StringUtils.*;
*
* <p>Concrete subclasses differ primarily on which {@link PropertySource} objects they
* add by default. {@code AbstractEnvironment} adds none. Subclasses should contribute
* property sources through the protected {@link #customizePropertySources()} hook, while
* clients should customize using {@link ConfigurableEnvironment#getPropertySources()} and
* working against the {@link MutablePropertySources} API. See
* property sources through the protected {@link #customizePropertySources(MutablePropertySources)}
* hook, while clients should customize using {@link ConfigurableEnvironment#getPropertySources()}
* and working against the {@link MutablePropertySources} API. See
* {@link ConfigurableEnvironment} Javadoc for usage examples.
*
* @author Chris Beams
@@ -387,6 +387,20 @@ public abstract class AbstractEnvironment implements ConfigurableEnvironment {
return systemProperties;
}
public void merge(ConfigurableEnvironment parent) {
for (PropertySource<?> ps : parent.getPropertySources()) {
if (!this.propertySources.contains(ps.getName())) {
this.propertySources.addLast(ps);
}
}
for (String profile : parent.getActiveProfiles()) {
this.activeProfiles.add(profile);
}
for (String profile : parent.getDefaultProfiles()) {
this.defaultProfiles.add(profile);
}
}
//---------------------------------------------------------------------
// Implementation of ConfigurablePropertyResolver interface

42
org.springframework.core/src/main/java/org/springframework/core/env/ConfigurableEnvironment.java vendored
View File

@@ -1,5 +1,5 @@
/*
* Copyright 2002-2011 the original author or authors.
* Copyright 2002-2012 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.
@@ -55,13 +55,14 @@ import java.util.Map;
* propertySources.replace(StandardEnvironment.SYSTEM_ENVIRONMENT_PROPERTY_SOURCE_NAME, mockEnvVars);
* </pre>
*
* When an {@link Environment} is being used by an ApplicationContext, it is important
* that any such PropertySource manipulations be performed <em>before</em> the context's
* {@link org.springframework.context.support.AbstractApplicationContext#refresh()
* refresh()} method is called. This ensures that all property sources are available
* during the container bootstrap process, including use by
* {@linkplain org.springframework.context.support.PropertySourcesPlaceholderConfigurer
* property placeholder configurers}.
* When an {@link Environment} is being used by an {@code ApplicationContext}, it is
* important that any such {@code PropertySource} manipulations be performed
* <em>before</em> the context's {@link
* org.springframework.context.support.AbstractApplicationContext#refresh() refresh()}
* method is called. This ensures that all property sources are available during the
* container bootstrap process, including use by {@linkplain
* org.springframework.context.support.PropertySourcesPlaceholderConfigurer property
* placeholder configurers}.
*
*
* @author Chris Beams
@@ -78,7 +79,6 @@ public interface ConfigurableEnvironment extends Environment, ConfigurableProper
* <p>Any existing active profiles will be replaced with the given arguments; call
* with zero arguments to clear the current set of active profiles. Use
* {@link #addActiveProfile} to add a profile while preserving the existing set.
*
* @see #addActiveProfile
* @see #setDefaultProfiles
* @see org.springframework.context.annotation.Profile
@@ -123,12 +123,10 @@ public interface ConfigurableEnvironment extends Environment, ConfigurableProper
* Return the value of {@link System#getenv()} if allowed by the current
* {@link SecurityManager}, otherwise return a map implementation that will attempt
* to access individual keys using calls to {@link System#getenv(String)}.
*
* <p>Note that most {@link Environment} implementations will include this system
* environment map as a default {@link PropertySource} to be searched. Therefore, it
* is recommended that this method not be used directly unless bypassing other
* property sources is expressly intended.
*
* <p>Calls to {@link Map#get(Object)} on the Map returned will never throw
* {@link IllegalAccessException}; in cases where the SecurityManager forbids access
* to a property, {@code null} will be returned and an INFO-level log message will be
@@ -140,12 +138,10 @@ public interface ConfigurableEnvironment extends Environment, ConfigurableProper
* Return the value of {@link System#getProperties()} if allowed by the current
* {@link SecurityManager}, otherwise return a map implementation that will attempt
* to access individual keys using calls to {@link System#getProperty(String)}.
*
* <p>Note that most {@code Environment} implementations will include this system
* properties map as a default {@link PropertySource} to be searched. Therefore, it is
* recommended that this method not be used directly unless bypassing other property
* sources is expressly intended.
*
* <p>Calls to {@link Map#get(Object)} on the Map returned will never throw
* {@link IllegalAccessException}; in cases where the SecurityManager forbids access
* to a property, {@code null} will be returned and an INFO-level log message will be
@@ -153,4 +149,24 @@ public interface ConfigurableEnvironment extends Environment, ConfigurableProper
*/
Map<String, Object> getSystemProperties();
/**
* Append the given parent environment's active profiles, default profiles and
* property sources to this (child) environment's respective collections of each.
* <p>For any identically-named {@code PropertySource} instance existing in both
* parent and child, the child instance is to be preserved and the parent instance
* discarded. This has the effect of allowing overriding of property sources by the
* child as well as avoiding redundant searches through common property source types,
* e.g. system environment and system properties.
* <p>Active and default profile names are also filtered for duplicates, to avoid
* confusion and redundant storage.
* <p>The parent environment remains unmodified in any case. Note that any changes to
* the parent environment occurring after the call to {@code merge} will not be
* reflected in the child. Therefore, care should be taken to configure parent
* property sources and profile information prior to calling {@code merge}.
* @param parent the environment to merge with
* @since 3.2
* @see org.springframework.context.support.AbstractApplicationContext#setParent
*/
void merge(ConfigurableEnvironment parent);
}

69
org.springframework.core/src/test/java/org/springframework/core/env/StandardEnvironmentTests.java vendored
View File

@@ -1,5 +1,5 @@
/*
* Copyright 2002-2011 the original author or authors.
* Copyright 2002-2012 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.
@@ -16,22 +16,6 @@
package org.springframework.core.env;
import static java.lang.String.format;
import static org.hamcrest.CoreMatchers.equalTo;
import static org.hamcrest.CoreMatchers.instanceOf;
import static org.hamcrest.CoreMatchers.is;
import static org.hamcrest.CoreMatchers.not;
import static org.hamcrest.CoreMatchers.notNullValue;
import static org.hamcrest.CoreMatchers.nullValue;
import static org.junit.Assert.assertSame;
import static org.junit.Assert.assertThat;
import static org.junit.Assert.fail;
import static org.junit.matchers.JUnitMatchers.hasItem;
import static org.junit.matchers.JUnitMatchers.hasItems;
import static org.springframework.core.env.AbstractEnvironment.ACTIVE_PROFILES_PROPERTY_NAME;
import static org.springframework.core.env.AbstractEnvironment.DEFAULT_PROFILES_PROPERTY_NAME;
import static org.springframework.core.env.AbstractEnvironment.RESERVED_DEFAULT_PROFILE_NAME;
import java.lang.reflect.Field;
import java.security.AccessControlException;
import java.security.Permission;
@@ -40,8 +24,18 @@ import java.util.Collections;
import java.util.Map;
import org.junit.Test;
import org.springframework.mock.env.MockPropertySource;
import static java.lang.String.*;
import static org.hamcrest.CoreMatchers.*;
import static org.junit.Assert.*;
import static org.junit.matchers.JUnitMatchers.*;
import static org.springframework.core.env.AbstractEnvironment.*;
/**
* Unit tests for {@link StandardEnvironment}.
*
@@ -62,6 +56,47 @@ public class StandardEnvironmentTests {
private ConfigurableEnvironment environment = new StandardEnvironment();
@Test
public void merge() {
ConfigurableEnvironment child = new StandardEnvironment();
child.setActiveProfiles("c1", "c2");
child.getPropertySources().addLast(
new MockPropertySource("childMock")
.withProperty("childKey", "childVal")
.withProperty("bothKey", "childBothVal"));
ConfigurableEnvironment parent = new StandardEnvironment();
parent.setActiveProfiles("p1", "p2");
parent.getPropertySources().addLast(
new MockPropertySource("parentMock")
.withProperty("parentKey", "parentVal")
.withProperty("bothKey", "parentBothVal"));
assertThat(child.getProperty("childKey"), is("childVal"));
assertThat(child.getProperty("parentKey"), nullValue());
assertThat(child.getProperty("bothKey"), is("childBothVal"));
assertThat(parent.getProperty("childKey"), nullValue());
assertThat(parent.getProperty("parentKey"), is("parentVal"));
assertThat(parent.getProperty("bothKey"), is("parentBothVal"));
assertThat(child.getActiveProfiles(), equalTo(new String[]{"c1","c2"}));
assertThat(parent.getActiveProfiles(), equalTo(new String[]{"p1","p2"}));
child.merge(parent);
assertThat(child.getProperty("childKey"), is("childVal"));
assertThat(child.getProperty("parentKey"), is("parentVal"));
assertThat(child.getProperty("bothKey"), is("childBothVal"));
assertThat(parent.getProperty("childKey"), nullValue());
assertThat(parent.getProperty("parentKey"), is("parentVal"));
assertThat(parent.getProperty("bothKey"), is("parentBothVal"));
assertThat(child.getActiveProfiles(), equalTo(new String[]{"c1","c2","p1","p2"}));
assertThat(parent.getActiveProfiles(), equalTo(new String[]{"p1","p2"}));
}
@Test
public void propertySourceOrder() {
ConfigurableEnvironment env = new StandardEnvironment();