springcloud 设置本地配置覆盖远程
@Configuration(proxyBeanMethods = false)
@EnableConfigurationProperties(PropertySourceBootstrapProperties.class)
public class PropertySourceBootstrapConfiguration
implements ApplicationContextInitializer<ConfigurableApplicationContext>, Ordered {
private void insertPropertySources(MutablePropertySources propertySources, List<PropertySource<?>> composite) {
//composite是配置中心的配置
MutablePropertySources incoming = new MutablePropertySources();
List<PropertySource<?>> reversedComposite = new ArrayList<>(composite);
// Reverse the list so that when we call addFirst below we are maintaining the same order of PropertySources Wherever we call addLast we can use the order in the List since the first item will end up before the rest
//调用了倒序排序，这是为了方便在调用addLast和addFirst方法的时候保证顺序是一致的，下面reversedComposite是调用addFirst和addAfter， composite是调用addLast和addBefore
Collections.reverse(reversedComposite);
for (PropertySource<?> p : reversedComposite) {
incoming.addFirst(p);
}
PropertySourceBootstrapProperties remoteProperties = new PropertySourceBootstrapProperties();
Binder.get(environment(incoming)).bind("", Bindable.ofInstance(remoteProperties));
//这个分支是远程覆盖本地，默认走这个分支
if (!remoteProperties.isAllowOverride()
|| (!remoteProperties.isOverrideNone() && remoteProperties.isOverrideSystemProperties())) {
for (PropertySource<?> p : reversedComposite) {
propertySources.addFirst(p);
}
return;
}
//这个分支就是本地覆盖远程
if (remoteProperties.isOverrideNone()) {
for (PropertySource<?> p : composite) {
propertySources.addLast(p);
}
return;
}
if (propertySources.contains(SYSTEM_ENVIRONMENT_PROPERTY_SOURCE_NAME)) {
if (!remoteProperties.isOverrideSystemProperties()) {
for (PropertySource<?> p : reversedComposite) {
propertySources.addAfter(SYSTEM_ENVIRONMENT_PROPERTY_SOURCE_NAME, p);
}
}
else {
for (PropertySource<?> p : composite) {
propertySources.addBefore(SYSTEM_ENVIRONMENT_PROPERTY_SOURCE_NAME, p);
}
}
}
else {
for (PropertySource<?> p : composite) {
propertySources.addLast(p);
}
}
}