Can I manually load #ConfigurationProperties without the Spring AppContext? - java

Is there any way to load a class marked with #ConfigurationProperties without using a Spring Context directly? Basically I want to reuse all the smart logic that Spring does but for a bean I manually instantiate outside of the Spring lifecycle.
I have a bean that loads happily in Spring (Boot) and I can inject this into my other Service beans:
#ConfigurationProperties(prefix="my")
public class MySettings {
String property1;
File property2;
}
See the spring docco for more info http://docs.spring.io/spring-boot/docs/current-SNAPSHOT/reference/htmlsingle/#boot-features-external-config-command-line-args
But now I need to access this bean from a class that is created outside of Spring (by Hibernate). The class is created so early in the app startup process that Spring Boot has not yet made the application context available through the classic lookup helper methods or roll-my-own static references.
So I instead want to do something like:
MySettings mySettings = new MySettings();
SpringPropertyLoadingMagicClass loader = new SpringPropertyLoadingMagicClass();
loader.populatePropertyValues(mySettings);
And have MySettings end up with all its values loaded, from the command line, system properties, app.properties, etc. Is there some class in Spring that does something like this or is it all too interwoven with the application context?
Obviously I could just load the Properties file myself, but I really want to keep Spring Boot's logic around using command line variables (e.g. --my.property1=xxx), or system variables, or application.properties or even a yaml file, as well as its logic around relaxed binding and type conversion (e.g. property2 is a File) so that it all works exactly the same as when used in the Spring context.
Possible or pipe dream?
Thanks for your help!

I had the same "issue".
Here is how I solved it in SpringBoot version 1.3.xxx and 1.4.1.
Let's say we have the following yaml configuration file:
foo:
apis:
-
name: Happy Api
path: /happyApi.json?v=bar
-
name: Grumpy Api
path: /grumpyApi.json?v=grrr
and we have the following ConfigurationProperties:
#ConfigurationProperties(prefix = "foo")
public class ApisProperties {
private List<ApiPath> apis = Lists.newArrayList();
public ApisProperties() {
}
public List<ApiPath> getApis() {
return apis;
}
public static class ApiPath {
private String name;
private String path;
public String getName() {
return name;
}
public void setName(final String aName) {
name = aName;
}
public String getPath() {
return path;
}
public void setPath(final String aPath) {
path = aPath;
}
}
}
Then, to do the "magic" things of Spring Boot programmatically (e.g. loading some properties in a static method), you can do:
private static ApisProperties apiProperties() {
try {
ClassPathResource resource;
resource = new ClassPathResource("/config/application.yml");
YamlPropertiesFactoryBean factoryBean;
factoryBean = new YamlPropertiesFactoryBean();
factoryBean.setSingleton(true); // optional depends on your use-case
factoryBean.setResources(resource);
Properties properties;
properties = factoryBean.getObject();
MutablePropertySources propertySources;
propertySources = new MutablePropertySources();
propertySources.addLast(new PropertiesPropertySource("apis", properties));
ApisProperties apisProperties;
apisProperties = new ApisProperties();
PropertiesConfigurationFactory<ApisProperties> configurationFactory;
configurationFactory = new PropertiesConfigurationFactory<>(apisProperties);
configurationFactory.setPropertySources(propertySources);
configurationFactory.setTargetName("foo"); // it's the same prefix as the one defined in the #ConfigurationProperties
configurationFactory.bindPropertiesToTarget();
return apisProperties; // apiProperties are fed with the values defined in the application.yaml
} catch (BindException e) {
throw new IllegalArgumentException(e);
}
}

Here's an update to ctranxuan's answer for Spring Boot 2.x. In our situation, we avoid spinning up a Spring context for unit tests, but do like to test our configuration classes (which is called AppConfig in this example, and its settings are prefixed by app):
public class AppConfigTest {
private static AppConfig config;
#BeforeClass
public static void init() {
YamlPropertiesFactoryBean factoryBean = new YamlPropertiesFactoryBean();
factoryBean.setResources(new ClassPathResource("application.yaml"));
Properties properties = factoryBean.getObject();
ConfigurationPropertySource propertySource = new MapConfigurationPropertySource(properties);
Binder binder = new Binder(propertySource);
config = binder.bind("app", AppConfig.class).get(); // same prefix as #ConfigurationProperties
}
}

The "magic" class you are looking for is PropertiesConfigurationFactory. But I would question your need for it - if you only need to bind once, then Spring should be able to do it for you, and if you have lifecycle issues it would be better to address those (in case they break something else).

This post is going into similar direction but extends the last answer with also validation and property placeholder resolutions.
Spring Boot Binder API support for #Value Annotations
#Value annotations in ConfigurationPropertys don't seem to bind properly though (at least if the referenced values are not part of the ConfigurationProperty's prefix namespace).

import org.springframework.boot.context.properties.bind.Binder
val binder = Binder.get(environment)
binder.bind(prefix, MySettings.class).get

Related

Fail to inject #Value in tests with Spring, Spock & Groovy

I have problems with injection #Value('${mybean.secret}') property into my bean during tests in Spock with Spring Boot & Groovy.
I have a very simple test class MyBeanTest
#ContextConfiguration(classes = [
MyAppConfig
])
#PropertySource([
"classpath:context/default-properties.yml"
])
class MyBeanTest extends Specification {
#Autowired
MyBean myBean
def "should populate properties "() {
expect:
myBean.secretProperty == "iCantTellYou"
}
}
And MyAppConfig.groovy as this:
#Configuration
class MyAppConfig {
#Bean
MyBean credential(#Value('${mybean.secret}') String secret) {
return new MyBean(secret)
}
}
When I run tests the value that is injected into secret is simply ${mybean.secret}.
The real value is not injected from properties file I enclose on test specification.
I'm using single-quote on #Value because of Groovy. Double quote with $ sign makes it being processed by groovy GString mechanism.
However, the problem doesn't occur on regular application run.
If I start application and put the breakpoint on the MyAppConfig#credential method the secret value is correctly read from the properties file, which are configured as follow:
#Configuration
#PropertySource(["classpath:context/default-properties.yml"])
class PropertiesConfig {
}
When I specify property from hand like this:
#TestPropertySource(properties = [
"mybean.secret=xyz"
])
class MyBeanTest extends Specification {
It works. The property is read. But it's not my goal, cause there's much more properties in the project and it would become cumbersone to define them everywhere from hand.
Can you spot the problem I am missing in this code?
The missing puzzle was YamlPropertySourceFactory.
public class YamlPropertySourceFactory implements PropertySourceFactory {
#Override
public PropertySource<?> createPropertySource(String name, EncodedResource encodedResource)
throws IOException {
YamlPropertiesFactoryBean factory = new YamlPropertiesFactoryBean();
factory.setResources(encodedResource.getResource());
Properties properties = factory.getObject();
return new PropertiesPropertySource(encodedResource.getResource().getFilename(), properties);
}
}
I was using yml properties files with nested properties:
mybean:
secret: xyz
And Spring was not loading them correctly.
I had to update #PropertySource annotation as well as follow:
#Configuration
#PropertySource(
value = ["classpath:context/default-properties.yml"],
factory = YamlPropertySourceFactory.class
)
class PropertiesConfig {
}
Now it works like a charm 😏.
I learned this on Baeldung website => https://www.baeldung.com/spring-yaml-propertysource

Use Spring #RefreshScope, #Conditional annotations to replace bean injection at runtime after a ConfigurationProperties has changed

I'm running a PoC around replacing bean injection at runtime after a ConfigurationProperties has changed. This is based on spring boot dynamic configuration properties support as well summarised here by Dave Syer from Pivotal.
In my application I have a simple interface implemented by two different concrete classes:
#Component
#RefreshScope
#ConditionalOnExpression(value = "'${config.dynamic.context.country}' == 'it'")
public class HelloIT implements HelloService {
#Override
public String sayHello() {
return "Ciao dall'italia";
}
}
and
#Component
#RefreshScope
#ConditionalOnExpression(value = "'${config.dynamic.context.country}' == 'us'")
public class HelloUS implements HelloService {
#Override
public String sayHello() {
return "Hi from US";
}
}
application.yaml served by spring cloud config server is:
config:
name: Default App
dynamic:
context:
country: us
and the related ConfigurationProperties class:
#Configuration
#ConfigurationProperties (prefix = "config.dynamic")
public class ContextHolder {
private Map<String, String> context;
Map<String, String> getContext() {
return context;
}
public void setContext(Map<String, String> context) {
this.context = context;
}
My client app entrypoint is:
#SpringBootApplication
#RestController
#RefreshScope
public class App1Application {
#Autowired
private HelloService helloService;
#RequestMapping("/hello")
public String hello() {
return helloService.sayHello();
}
First time I browse http://locahost:8080/hello endpoint it returns "Hi from US"
After that I change country: us in country: it in application.yaml in spring config server, and then hit the actuator/refresh endpoint ( on the client app).
Second time I browse http://locahost:8080/hello it stills returns "Hi from US" instead of "ciao dall'italia" as I would expect.
Is this use case supported in spring boot 2 when using #RefreshScope? In particular I'm referring to the fact of using it along with #Conditional annotations.
This implementation worked for me:
#Component
#RefreshScope
public class HelloDelegate implements HelloService {
#Delegate // lombok delegate (for the sake of brevity)
private final HelloService delegate;
public HelloDelegate(
// just inject value from Spring configuration
#Value("${country}") String country
) {
HelloService impl = null;
switch (country) {
case "it":
this.delegate = new HelloIT();
break;
default:
this.delegate = new HelloUS();
break;
}
}
}
It works the following way:
When first invocation of service method happens Spring creates bean HelloDelegate with configuration effective at that moment; bean is put into refresh scope cache
Because of #RefreshScope whenever configuration is changed (country property particularly in this case) HelloDelegate bean gets cleared from refresh scope cache
When next invocation happens, Spring has to create bean again because it does not exist in cache, so step 1 is repeated with new country property
As far as I watched the behavior of this implementation, Spring will try to avoid recreating RefreshScope bean if it's configuration was untouched.
I was looking for more generic solution of doing such "runtime" implementation replacement when found this question. This implementation has one significant disadvantage: if delegated beans have complex non-homogeneous configuration (e.g. each bean has it's own properties) code becomes lousy and therefore unsafe.
I use this approach to provide additional testability for artifacts. So that QA would be able to switch between stub and real integration without significant efforts. I would strongly recommend to avoid using such approach for business functionality.

Read qualified yaml file with prefix without using annotations or xml

My use case is a bit oddball but basically, I'd like to read a portion of a yaml file and map it to the appropriate java object in a spring application. This is a pretty common and trivial operation in spring (just use #ConfigurationProperties ).
However, in my case, I'd like to accomplish this reading earlier in the lifecycle i.e. by the time the BeanFactoryPostProcessor hooks in - in order to use the instructions specified in yml to dynamically create a number of beans.
I can get this working with application.properties but not with application.yml
I was hoping to use yml in order leverage mapping part of the yml to POJO and also utilize hierarchical mapping files and data structures (lists, maps etc).
Here's an example of how to read application.properties. https://blog.pchudzik.com/201705/dynamic-beans/
I set up a simple skeleton project at https://github.com/balamuru/yaml-loader to try out different techniques.
Any ideas ?
#Component
#EnableConfigurationProperties(SampleDataConfig.class)
class ConfigurableBeanFactory implements BeanFactoryPostProcessor, InitializingBean {
private List<String> beanInstances = new ArrayList<>();
#Override
public void postProcessBeanFactory(ConfigurableListableBeanFactory beanFactory) throws BeansException {
final BeanDefinitionRegistry registry = (BeanDefinitionRegistry) beanFactory;
Map<String, SampleDataConfig> beans = beanFactory.getBeansOfType(SampleDataConfig.class);
System.err.println("");
beanInstances.forEach(instance -> {
registry.registerBeanDefinition(instance, BeanDefinitionBuilder
.rootBeanDefinition(SampleDataConfig.class)
.addConstructorArgValue(instance)
.getBeanDefinition());
});
}
#Override
public void afterPropertiesSet() throws Exception {
// this.beanInstances = asList(PropertiesLoaderUtils
// .loadProperties(new ClassPathResource("/application.properties"))
// .getProperty("dynamic-beans.instances", "")
// .split(","));
/**
* Rather than reading from application.properties,
* I would like to be able to load up the relevant prefix qualified segments (com.foo.bar.stuff) mapping to my POJO (SampleDataConfig,class)
* loaded from application.yml
*/
}
}
Internally, spring uses the following mechanism, but I was hoping there is an easier way to leverage this without re-inventing the spring :)
public class ConfigurationPropertiesBindingPostProcessor ...{
.
.
private void postProcessBeforeInitialization(Object bean, String beanName,
ConfigurationProperties annotation) {
Object target = bean;
PropertiesConfigurationFactory<Object> factory = new PropertiesConfigurationFactory<Object>(
target);
factory.setPropertySources(this.propertySources);
factory.setValidator(determineValidator(bean));
// If no explicit conversion service is provided we add one so that (at least)
// comma-separated arrays of convertibles can be bound automatically
factory.setConversionService(this.conversionService == null
? getDefaultConversionService() : this.conversionService);
if (annotation != null) {
factory.setIgnoreInvalidFields(annotation.ignoreInvalidFields());
factory.setIgnoreUnknownFields(annotation.ignoreUnknownFields());
factory.setExceptionIfInvalid(annotation.exceptionIfInvalid());
factory.setIgnoreNestedProperties(annotation.ignoreNestedProperties());
if (StringUtils.hasLength(annotation.prefix())) {
factory.setTargetName(annotation.prefix()); //====> use annotation prefix
}
}
try {
factory.bindPropertiesToTarget(); //===> bind properties
}
Thanks
YamlPropertiesFactoryBean yaml = new YamlPropertiesFactoryBean();
yaml.setResources(new ClassPathResource("application.yml"));
configProperty = yaml.getObject();
Set<Object> keys = configProperty.keySet();
Below is my YAML configuration, which looks like:
template:
config:
broker-urls:
- tcp://127.0.0.1:61616
- tcp://127.0.0.1:61617
- tcp://127.0.0.1:61618
qeues:
- Test
- Demo
- Qeue3
After applying above code you will get converted properties like below:
template.config.broker-urls[0]=tcp://127.0.0.1:61616
template.config.broker-urls[1]=tcp://127.0.0.1:61617
template.config.broker-urls[1]=tcp://127.0.0.1:61618
template.config.qeues[0]=Test
template.config.qeues[1]=Demo
template.config.qeues[1]=Qeue3

How do I configure Spring to partially and optionally override properties?

I would like to have a properties setup which can, on certain environments, override specific properties. For example, our default JDBC properties for dev are:
db.driverClassName=com.mysql.jdbc.Driver
db.url=jdbc:mysql://localhost:3306/ourdb
db.username=root
db.password=
The problem is that some of our devs would like to have a different username/password on the db, or possibly even a non locally hosted db. The same is true for our rabbitMQ configuration, which currently uses a similar localhost, guest/guest setup. Being able to override the properties of certain elements of this configuration on a per-developer basis would allow us to move much of the infrastructure/installation requirements for building the software off the local machine and onto dedicated servers.
I have set-up a simple project to wrap my head around the configuration required to achieve what I want, and this is my first foray into the world of spring property configuration, since up till now, property loading and management is done with some custom code. Here is my setup:
class Main_PropertyTest {
public static void main(String[] args) {
String environment = System.getenv("APPLICATION_ENVIRONMENT"); // Environment, for example: "dev"
String subEnvironment = System.getenv("APPLICATION_SUB_ENVIRONMENT"); // Developer name, for example: "joe.bloggs"
System.setProperty("spring.profiles.active", environment);
System.setProperty("spring.profiles.sub", subEnvironment);
try(AnnotationConfigApplicationContext context = new AnnotationConfigApplicationContext(PropertyTestConfiguration.class)) {
Main_PropertyTest main = context.getBean(Main_PropertyTest.class);
main.printProperty();
}
}
private final String property;
public Main_PropertyTest(String property) {
this.property = property;
}
public void printProperty() {
System.out.println("And the property is: '" + property + "'.");
}
}
And my configuration:
#Configuration
public class PropertyTestConfiguration {
#Bean
public static PropertySourcesPlaceholderConfigurer primaryPlaceholderConfigurer() {
PropertySourcesPlaceholderConfigurer propertySourcesPlaceholderConfigurer = new PropertySourcesPlaceholderConfigurer();
propertySourcesPlaceholderConfigurer.setLocation(new ClassPathResource(System.getProperty("spring.profiles.active") + ".main.properties"));
return propertySourcesPlaceholderConfigurer;
}
#Bean
public static PropertySourcesPlaceholderConfigurer secondaryPlaceholderConfigurer() {
PropertySourcesPlaceholderConfigurer propertySourcesPlaceholderConfigurer = new PropertySourcesPlaceholderConfigurer();
propertySourcesPlaceholderConfigurer.setLocation(new ClassPathResource(System.getProperty("spring.profiles.sub") + ".main.properties"));
propertySourcesPlaceholderConfigurer.setIgnoreResourceNotFound(true);
propertySourcesPlaceholderConfigurer.setIgnoreResourceNotFound(true);
propertySourcesPlaceholderConfigurer.setOrder(-1);
return propertySourcesPlaceholderConfigurer;
}
#Bean
public Main_PropertyTest main_PropertyTest(#Value("${main.property}") String property) {
Main_PropertyTest main_PropertyTest = new Main_PropertyTest(property);
return main_PropertyTest;
}
}
And for completeness, my dev.main.properties and test.main.properties:
main.property=dev
main.property=test
The main problem is that I get an illegal argument exception. As far as I can tell, what I have written should be the javaconfig equivalent of this method: http://taidevcouk.wordpress.com/2013/07/04/overriding-a-packaged-spring-application-properties-file-via-an-external-file/
Unfortunately I get the following error: java.lang.IllegalArgumentException: Could not resolve placeholder 'main.property' in string value "${main.property}". Note that I also need to take care of the case where there is no sub-environment, and this is the case I have started with (although I get the same error even if both files exist). If I remove the bean which sets up the second propertysourcesplaceholderconfigurer, then it all works fine (by which I mean dev.main.properties is loaded and "And the property is: 'dev'." is printed out).
A secondary problem is that the code doesn't look great, and each layer of the system will need two PSPC's set-up so that they can access these properties. Furthermore, it requires a lot of manual calls to System.getProperty(), since I couldn't pass ${spring.profiles.active} to PSPC.setLocation();
Note: I have tried #PropertySources({primaryproperties, secondaryProperties}), but this fails because secondaryProperties does not exist. I have also tried #Autowired Environment environment; and getting the properties from that, but the secondary PSPC causes the environment to not be autowired...
So following this lengthy explanation, my questions are:
Is this the right way of solving this problem?
If so, what is wrong with my configuration?
How can I simplify the configuration (if at all)?
Is there an alternative mechanism available which would solve my problem?
Thank you for your time! :)
Your configuration is flawed when configuring BeanFactoryPostProcessor with java config the methods should be static. However it can be even easier, instead of registering your own PropertySourcesPlaceholderConfigurer utilize the default #PropertySource support.
Rewerite your jav config to the following
#Configuration
#PropertySource(name="main", value= "${spring.profiles.active}.main.properties")
public class PropertyTestConfiguration {
#Autowired
private Environment env;
#PostConstruct
public void initialize() {
String resource = env.getProperty("spring.profiles.sub") +".main.properties";
Resource props = new ClassPathResource(resource);
if (env instanceof ConfigurableEnvironment && props.exists()) {
MutablePropertySources sources = ((ConfigurableEnvironment) env).getPropertySources();
sources.addBefore("main", new ResourcePropertySource(props));
}
}
#Bean
public Main_PropertyTest main_PropertyTest(#Value("${main.property}") String property) {
Main_PropertyTest main_PropertyTest = new Main_PropertyTest(property);
return main_PropertyTest;
}
}
This should first load the dev.main.properties and additionally the test.main.properties which will override the earlier loaded properties (when filled ofcourse).
I had a similar issue with overwriting already existing properties in integration tests
I came up with this solution:
#RunWith(SpringJUnit4ClassRunner.class)
#SpringApplicationConfiguration(classes = {
SomeProdConfig.class,
MyWebTest.TestConfig.class
})
#WebIntegrationTest
public class MyWebTest {
#Configuration
public static class TestConfig {
#Inject
private Environment env;
#PostConstruct
public void overwriteProperties() throws Exception {
final Map<String,Object> systemProperties = ((ConfigurableEnvironment) env)
.getSystemProperties();
systemProperties.put("some.prop", "test.value");
}
}

Dynamically accessing properties using Spring 3.1's property abstraction

I'm trying to dynamically access properties from Spring's Environment property abstraction.
I declare my property files like this:
<context:property-placeholder
location="classpath:server.common.properties,
classpath:server.${my-environment}.properties" />
In my property file server.test.properties, I define the following:
myKey=foo
Then, given the following code:
#Component
public class PropertyTest {
#Value("${myKey}")
private String propertyValue;
#Autowired
private PropertyResolver propertyResolver;
public function test() {
String fromResolver = propertyResolver.getProperty("myKey");
}
}
When I run this code, I end up with propertyValue='foo', but fromResolver=null;
Receiving propertyValue indicates that the properties are being read, (and I know this from other parts of my code). However, attempting to look them up dynamically is failing.
Why? How can I dynamically look up property values, without having to use #Value?
Simply adding a <context:property-placeholder/> doesn't add a new PropertySource to the Environment. If you read the article you linked completely, you'll see it suggests registering an ApplicationContextInitializer in order to add new PropertySources so they'll be available in the way you're trying to use them.
To get this to work I had to split out the reading of the properties into a #Configuration bean, as shown here.
Here's the complete example:
#Configuration
#PropertySource("classpath:/server.${env}.properties")
public class AngularEnvironmentModuleConfiguration {
private static final String PROPERTY_LIST_NAME = "angular.environment.properties";
#Autowired
private Environment environment;
#Bean(name="angularEnvironmentProperties")
public Map<String,String> getAngularEnvironmentProperties()
{
String propertiesToInclude = environment.getProperty(PROPERTY_LIST_NAME, "");
String[] propertyNames = StringUtils.split(propertiesToInclude, ",");
Map<String,String> properties = Maps.newHashMap();
for (String propertyName : propertyNames)
{
String propertyValue = environment.getProperty(propertyName);
properties.put(propertyName, propertyValue);
}
return properties;
}
}
The set of properties are then injected elsewhere, to be consumed.

Categories

Resources