I want disable automatically delete JMS queue in spring boot application - spring-boot

Auto deletion of queues should be turned off,
1)If set "ems_value=true" in application.property file
#ConditionalOnProperty(name = "ems_value")
public class JmsConfiguration {
// Here get JMS connection
In this case what are mentioned queue names in application property file Its created by spring.
2)If set "ems_value=false" in application.property file
Queues deleted by spring class.
How can i disable or stop to delete queues.

It will only work on startup anyway, but you can always use 2 different beans that will do required job for you. Have once component with
#ConditionalOnProperty(name = "ems_value", havingValue="true")
that will do whatever you require, and have another component with
#ConditionalOnProperty(name = "ems_value", havingValue="false")
that will do cleanup operations only.

Related

spring #JmsListener non compile time replacement

Looking for some alternative JMS destination configuration. The most common way of configuring destination and listener is by using annotation.
#JmsListener(destination = destination)
public void fetchMessage(final Message message) {
However, destination property have to be provided during the compile time. How to quickly replace it using some property which will be resolved only during runtime?
You can use a property placeholder for the destination
#JmsListener(destination = "${queue.name}")
Then set the property in some property source available to the application (e.g. application.properties or application.yml for a boot app, or a system property -Dqueue.name=foo for any app).

Is it possible to automatically create queues without RabbitAutoConfiguration.class? AMQP

I'm using 2.1.0.RELEASE version of Spring boot with AMQP. Unfortunetly I need to connect to several different RabbitMQ servers. I had to exclude RabbitAutoConfiguration.class besause due to changes in above version of spring it's impossible to start without one of the ConnectionFactory beans as primary, but even if I set one of them as #Primary, obviously it doesn't work, because how would amqp/spring-boot know which queue to create on which server...
so, is it possible to automatically create queues on different servers with auto configuration disabled?
Yes, you need a RabbitAdmin for each connection factory.
By default all components will be declared on all brokers, but you can add conditions. See Conditional Declaration.
By default, all queues, exchanges, and bindings are declared by all RabbitAdmin instances (assuming they have auto-startup="true") in the application context.
#Bean
public Queue queue1() {
Queue queue = new Queue("foo");
queue.setAdminsThatShouldDeclare(admin1());
return queue;
}

Spring boot application properties load process change programatically to improve security

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.

Refresh springboot configuration dynamically

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();
}
}

Reload property value when external property file changes ,spring boot

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;
}

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