Is there any way to refresh springboot configuration as soon as we change .properties file?
I came across spring-cloud-config and many articles/blogs suggested to use this for a distributed environment. I have many deployments of my springboot application but they are not related or dependent on one another. I also looked at few solutions where they suggested providing rest endpoints to refresh configs manually without restarting application. But I want to refresh configuration dynamically whenever I change .properties file without manual intervention.
Any guide/suggestion is much appreciated.
Can you just use the Spring Cloud Config "Server" and have it signal to your Spring Cloud client that the properties file changed. See this example:
https://spring.io/guides/gs/centralized-configuration/
Under the covers, it is doing a poll of the underlying resource and then broadcasts it to your client:
#Scheduled(fixedRateString = "${spring.cloud.config.server.monitor.fixedDelay:5000}")
public void poll() {
for (File file : filesFromEvents()) {
this.endpoint.notifyByPath(new HttpHeaders(), Collections
.<String, Object>singletonMap("path", file.getAbsolutePath()));
}
}
If you don't want to use the config server, in your own code, you could use a similar scheduled annotation and monitor your properties file:
#Component
public class MyRefresher {
#Autowired
private ContextRefresher contextRefresher;
#Scheduled(fixedDelay=5000)
public void myRefresher() {
// Code here could potentially look at the properties file
// to see if it changed, and conditionally call the next line...
contextRefresher.refresh();
}
}
Related
I have spring boot micro-service with database credentials define in the application properties.
spring.datasource.url=<<url>>
spring.datasource.username=<<username>>
spring.datasource.password=<<password>>
We do not use spring data source to create the connection manually. Only Spring create the database connection with JPA.(org.springframework.boot.autoconfigure.orm.jpa.HibernateJpaAutoConfiguration)
We only provide the application properties, but spring create the connections automatically to use with the database connection pool.
Our requirement to enhance the security without using db properties in clear text. Two possible methods.
Encrypt the database credentials
Use the AWS secret manager. (then get the credential with the application load)
For the option1, jasypt can be used, since we are just providing the properties only and do not want to create the data source manually, how to do to understand by the spring framework is the problem. If better I can get some working sample or methods.
Regarding the option-2,
first we need to define secretName.
use the secertName and get the database credentials from AWS secret manager.
update the application.properties programatically to understand by spring framework. (I need to know this step)
I need to use either option1 and option2. Mentioned the issues with each option.
What you could do is use environment variables for your properties. You can use them like this:
spring.datasource.url=${SECRET_URL}
You could then retrieve these and start your Spring process using a ProcessBuilder. (Or set the variables any other way)
I have found the solution for my problem.
We need to define org.springframework.context.ApplicationListenerin spring.factories file. It should define the required application context listener like below.
org.springframework.context.ApplicationListener=com.sample.PropsLoader
PropsLoader class is like this.
public class PropsLoader implements ApplicationListener<ApplicationEnvironmentPreparedEvent> {
#Override
public void onApplicationEvent(ApplicationEnvironmentPreparedEvent event) {
ConfigurableEnvironment environment = event.getEnvironment();
String appEnv = environment.getProperty("application.env");
//set new properties based on the application environment.
// calling other methods and depends on the enviornment and get the required value set
Properties props = new Properties();
props.put("new_property", "value");
environment.getPropertySources().addFirst(new PropertiesPropertySource("props", props));
}
}
spring.factories file should define under the resources package and META-INF
folder.
This will set the application context with new properties before loading any other beans.
When we use 'KeycloakSpringBootConfigResolver' for reading the keycloak configuration from Spring Boot properties file instead of keycloak.json.
Now there are guidelines to implement a multi-tenant application using keycloak by overriding 'KeycloakConfigResolver' as specified in http://www.keycloak.org/docs/2.3/securing_apps_guide/topics/oidc/java/multi-tenancy.html.
The steps defined here can only be used with keycloak.json.
How can we adapt this to a Spring Boot application such that keycloak properties are read from the Spring Boot properties file and multi-tenancy is achieved.
You can access the keycloak config you secified in your application.yaml (or application.properties) if you inject org.keycloak.representations.adapters.config.AdapterConfig into your component.
#Component
public class MyKeycloakConfigResolver implements KeycloakConfigResolver {
private final AdapterConfig keycloakConfig;
public MyKeycloakConfigResolver(org.keycloak.representations.adapters.config.AdapterConfig keycloakConfig) {
this.keycloakConfig = keycloakConfig;
}
#Override
public KeycloakDeployment resolve(OIDCHttpFacade.Request request) {
// make a defensive copy before changing the config
AdapterConfig currentConfig = new AdapterConfig();
BeanUtils.copyProperties(keycloakConfig, currentConfig);
// changes stuff here for example compute the realm
return KeycloakDeploymentBuilder.build(currentConfig);
}
}
After several trials, the only feasible option for spring boot is to have
Multiple instances of the spring boot application running with different spring 'profiles'.
Each application instance can have its own keycloak properties (as it is under different profiles) including the realm.
The challenge is to have an upgrade path for all instances for version upgrades/bug fixes, but I guess there are multiple strategies already implemented (not part of this discussion)
there is a ticket regarding this problem: https://issues.jboss.org/browse/KEYCLOAK-4139?_sscc=t
Comments for that ticket also talk about possible workarounds intervening in servlet setup of the service used (Tomcat/Undertow/Jetty), which you could try.
Note that the documentation you linked in your first comment is super outdated!
By default Spring Boot will automatically load properties from classpath:/application.properties
I want to know where is this auto configuration source code.
I want to exclude from my app.
IE: #EnableAutoConfiguration(exclude=XXXXAutoconfiguration.class)
The reason is:
Because I cannot override the default application.properties by an external property using #PropertySource
#SpringBootApplication
#ComponentScan(basePackages = {"com.test.green.ws"})
#PropertySource(value = {"classpath:/application.properties", "file:/opt/green-ws/application.properties"})
public class GreenWSApplication {
public static void main(String[] args) {
SpringApplication.run(GreenWSApplication.class, args);
}
}
There are many ways to override property keys without disabling the whole externalized configuration feature; and that's actually the goal.
You can see here the order the properties are considered in. For example, you can add that external properties file in a config folder right next to the packaged JAR, or even configure the file location yourself.
Now if you really want to disable all of that (and the Boot team strongly suggests not to do that), you can register your own EnvironmentPostProcessor (see here) and remove PropertySources from MutablePropertySources, which you can fetch with configurableEnvironment. getPropertySources().
There's no easier way to do that because:
this comes really early in the application init phase, before auto-configurations
this is not something you should do, as it will have many side effects
I am using spring boot, and I have two external properties files, so that I can easily change its value.
But I hope spring app will reload the changed value when it is updated, just like reading from files. Since property file is easy enough to meet my need, I hope I don' nessarily need a db or file.
I use two different ways to load property value, code sample will like:
#RestController
public class Prop1Controller{
#Value("${prop1}")
private String prop1;
#RequestMapping(value="/prop1",method = RequestMethod.GET)
public String getProp() {
return prop1;
}
}
#RestController
public class Prop2Controller{
#Autowired
private Environment env;
#RequestMapping(value="/prop2/{sysId}",method = RequestMethod.GET)
public String prop2(#PathVariable String sysId) {
return env.getProperty("prop2."+sysId);
}
}
I will boot my application with
-Dspring.config.location=conf/my.properties
I'm afraid you will need to restart Spring context.
I think the only way to achieve your need is to enable spring-cloud. There is a refresh endpoint /refresh which refreshes the context and beans.
I'm not quite sure if you need a spring-cloud-config-server (its a microservice and very easy to build) where your config is stored(Git or svn). Or if its also useable just by the application.properties file in the application.
Here you can find the doc to the refresh scope and spring cloud.
You should be able to use Spring Cloud for that
Add this as a dependency
compile group: 'org.springframework.cloud', name: 'spring-cloud-starter', version: '1.1.2.RELEASE'
And then use #RefreshScope annotation
A Spring #Bean that is marked as #RefreshScope will get special treatment when there is a configuration change. This addresses the problem of stateful beans that only get their configuration injected when they are initialized. For instance if a DataSource has open connections when the database URL is changed via the Environment, we probably want the holders of those connections to be able to complete what they are doing. Then the next time someone borrows a connection from the pool he gets one with the new URL.
Also relevant if you have Spring Actuator
For a Spring Boot Actuator application there are some additional management endpoints:
POST to
/env to update the Environment and rebind #ConfigurationProperties and log levels
/refresh for re-loading the boot strap context and refreshing the #RefreshScope beans
Spring Cloud Doc
(1) Spring Cloud's RestartEndPoint
You may use the RestartEndPoint: Programatically restart Spring Boot application / Refresh Spring Context
RestartEndPoint is an Actuator EndPoint, bundled with spring-cloud-context.
However, RestartEndPoint will not monitor for file changes, you'll have to handle that yourself.
(2) devtools
I don't know if this is for a production application or not. You may hack devtools a little to do what you want.
Take a look at this other answer I wrote for another question: Force enable spring-boot DevTools when running Jar
Devtools monitors for file changes:
Applications that use spring-boot-devtools will automatically restart
whenever files on the classpath change.
Technically, devtools is built to only work within an IDE. With the hack, it also works when launched from a jar. However, I may not do that for a real production application, you decide if it fits your needs.
I know this is a old thread, but it will help someone in future.
You can use a scheduler to periodically refresh properties.
//MyApplication.java
#EnableScheduling
//application.properties
management.endpoint.refresh.enabled = true
//ContextRefreshConfig.java
#Autowired
private RefreshEndpoint refreshEndpoint;
#Scheduled(fixedDelay = 60000, initialDelay = 10000)
public Collection<String> refreshContext() {
final Collection<String> properties = refreshEndpoint.refresh();
LOGGER.log(Level.INFO, "Refreshed Properties {0}", properties);
return properties;
}
//add spring-cloud-starter to the pom file.
Attribues annotated with #Value is refreshed if the bean is annotated with #RefreshScope.
Configurations annotated with #ConfigurationProperties is refreshed without #RefreshScope.
Hope this will help.
You can follow the ContextRefresher.refresh() code implements.
public synchronized Set<String> refresh() {
Map<String, Object> before = extract(
this.context.getEnvironment().getPropertySources());
addConfigFilesToEnvironment();
Set<String> keys = changes(before,
extract(this.context.getEnvironment().getPropertySources())).keySet();
this.context.publishEvent(new EnvironmentChangeEvent(context, keys));
this.scope.refreshAll();
return keys;
}
We want to use Spring Cloud for AWS SQS, but it seems to me that it only allows us to specify region. Can we fake it so that it uses ElasticMQ (on localhost:9320 for instance)? I didn't find an easy way to do this without editing hosts file and putting certificates on localhost
I found a way after some research.
You should set an endpoint after AmazonSQS instance is injected in order to override the already set endpoint, as so:
#Autowired
public void setAmazonSqs(AmazonSQS amazonSqs)
{
this.amazonSqs = amazonSqs;
// use elasticMQ if spring default profile is used; no active profiles
if (environment.getActiveProfiles().length == 0)
{
amazonSqs.setEndpoint("http://localhost:9320");
}
}
it is up to you if you're going to use QueueMessagingTemplate, anyway you should modify the injected AmazonSQS instance.