I am building an application (Spring Boot 1.4.2) where i would like to offer an administrator the option to enable syslog but i want to avoid him/her having to manually edit any config files - in this case logstash-spring.xml.
Therefore i am trying to understand how i can achieve using a logback-spring.xml file as a baseline (e.g. define file based log options, levels etc. - settings i dont want the administrator to change) and on top of that provide a functionality at runtime where an administrator can add or change a syslog appender.
I have listed what i see as requirements:
The changes made to the Logger should be persisted after the Spring Boot application is restarted.
Ideally the syslog server info (name, port) are kept in my persistence layer (H2, hibernate) but i am not sure if that is possible as i guess the logging framework is being injected prior to my persistence layer?
The syslog appender that i want to add should be referenced by root logger so that all the packages i have configured logging for would go to syslog (not sure if this is just "how it works per default")
Also i dont know if i could simply treat logback-spring.xml as a regular XML object and use for example JAXB to manipulate that file and use the autoscan feature of Logback to simply read in the new changes?
I have played around with defining a Logger #Bean:
#Bean
public Logger logger() {
LoggerContext lc = (LoggerContext) LoggerFactory.getILoggerFactory();
// excluded implementation
}
This is being picked up by Spring Boot but that brings me to the 2 items i have listed above that i dont know how or where i would store the syslog server information the administrator would provide.
UPDATE:
I wrote the following which meets the 3 requirements above however i would appreciate any feedback on the actual implementation as i am very new to Spring and Java.
GitHub repository with implementation - spring-boot-logback-syslog
I managed to use the example i posted in my Github repo in my designated application and with that i am answering my own questions based on the implementation in that repo.
Please refer to the README for full details on how it was implemented.
UPDATE: As part of Spring Boot 1.5.1 there is an actuator that can set the logging level during runtime: Production Ready Loggers
Not necessarily 100% related to this topic but this was one of the requirements i had for the implementation as well as changing syslog related settings.
Related
We are looking for log level change on runtime by updating the log level in the application-env.yml file. We are not allowed to use any endpoint/URL on the various higher environment so we can't leverage the spring actuator's provided functionality to change log level on runtime.
We believe that there should be something which can be combined with #RefreshScope of spring cloud and which allows us to just make changes in property/yml file and it will be get reflected on runtime.
We are setting up microservice framework.
We use following stack for distributed tracing.
Spring boot
Kafka
Zipkin
Following is how the configuration is done
In gradle.build (or pom.xml) following starter dependencies added
compile 'org.springframework.cloud:spring-cloud-starter-sleuth'
compile 'org.springframework.cloud:spring-cloud-sleuth-zipkin'
compile 'org.springframework.cloud:spring-cloud-starter-bus-kafka'
Add one AlwaysSampler bean
#Bean
public Sampler defaultSampler() {
return Sampler.ALWAYS_SAMPLE;
}
If we have kafka running, things work automatically.
But if kafka is not running, server does not start - this is mostly the case for development environment.
If I want to stop this, I have to comment out all the code mentioned here (as we use starter dependency with spring boot, it automatically configures as I understand).
Can we just make some changes in properties (or yaml) files so that I don't need to go and comment out all these code?
Or probably another way to disable this without doing some commenting, etc.
You can add the following setting on your properties key to disable zipkin, source.
spring.zipkin.enabled=false
Better yet, create separate development properties (like application-dev.properties) to avoid changing above setting everytime you want to run in your machine: https://stackoverflow.com/a/34846351/4504053
I have a Spring boot application which use logback.xml for logging configurations.I am looking for options to dynamically change log level.
For instance if I have deployed an app with loglevel as ERROR,Let say I want to change this to INFO but I don't want to redeploy/restart my JVM.
Is there any possibility we can configure logback.xml like config server to achieve this
You can configure Logback to Automatically reloading configuration file upon modification
Yes, this is quite possible. Expose a rest endpoint where you supply the className and log level. With slf4j you can get the LoggerContext and change the level.
LoggerContext context = (LoggerContext) LoggerFactory.getILoggerFactory();
context.getLogger(className).setLevel(Level.valueOf(level));
Apache Commons logging and others have similar features.
If you are using spring cloud then you can have this in your yml file
logging:
level:
root: INFO
Then you can change it and refresh the configuration using actuator refresh to fetch new configuration changes no need to restart the service.
Also if you need some sort of UI to do this stuff you can explore the Spring-cloud-dashboard It is pretty cool and uses the features from the actuator to do and show you a lot of stuff not only changing log levels.
I want to change the log level of a Spring Boot application that is running.
Is it possible to change the log level at runtime? Right now I have the logger configuration in my jar itself.
Changing the log level while the application is running is part of the underlying logger implementation.
You did not specify the logger implementation you are using so I will assume you are using the default logback provided via the spring-boot-starter-logging or spring-boot-starter-web dependencies.
Comment out any logger related configurations from application.properties
e.g.
#logging.path=logs
#logging.level.org.springframework.web= INFO
#logging.level.=INFO
Add logback.xml in the root of your classpath with tag
See http://logback.qos.ch/manual/jmxConfig.html
Start the application and open JConsole and go to MBeans tab.
Select the package ch.qos.logback.classic.JMxConfigurator.Under default locate the setLoggerLevel operation
e.g. org.springframework.web, DEBUG
The change will be effective immediately.
For other logger libraries see the spring boot user guide
http://docs.spring.io/spring-boot/docs/current/reference/html/howto-logging.html
And library specific information e.g. for log4j
http://www.sureshpw.com/2012/04/dynamic-logging-with-log4j.html
A different approach is to repeat the about steps without JMX and use configuration watcher
Logback Automatically reloading configuration file upon modification
Log4j configureAndWatch(java.lang.String, long)
If you want to change the logging level of an already running Spring Boot application you can take a look at spring-cloud-config. Refer to:
http://cloud.spring.io/spring-cloud-config/:
Spring Cloud Config provides server and client-side support for externalized configuration in a distributed system. With the Config Server you have a central place to manage external properties for applications across all environments.
You can centrally manage the properties in config server and in your current application - applications.properties file (check bootstrap.properties) create an entry for
spring.application.name=application name
Using #RefreshScope annotation in your client application you will be able to refresh your application runtime and see the updated logging level property.
With the release of Spring Boot 1.5, if you have actuator in your Boot application you can do this through an out of the box REST API.
1.5 actuator provides an endpoint called 'loggers' which you can GET to view the configuration, and POST to make runtime changes.
Ex.
curl -i -X POST -H 'Content-Type: application/json' -d '{"configuredLevel": "DEBUG"}' http://localhost:8080/loggers/org.springframwork
I'm using Spring 2.5.6. I have a bean whose properties are being assign from a property file via a PropertyPlaceholderConfigurer. I'm wondering whether its possible to have the property of the bean updated when the property file is modified. There would be for example some periodic process which checks the last modified date of the property file, and if it has changed, reload the bean.
I'm wondering if there is already something that satisfies my requirements. If not, what would be the best approach to solving this problem?
Thanks for your help.
Might also look into useing Spring's PropertyOverrideConfigurer. Could re-read the properties and re-apply it in some polling/schedular bean.
It does depend on how the actual configured beans use these properties. They might, for example, indirectly cache them somewhere themself.
If you want dynamic properties at runtime, perhaps another way to do it is JMX.
One way to do this is to embed a groovy console in your application. Here's some instructions. They were very simple to do, btw - took me very little time even though I'm not that familiar with groovy.
Once you do that you can simply go into the console and change values inside the live application on the fly.
You might try to use a custom scope for the bean that recreates beans on changes of the properties file. See my more extensive answer here.
Spring Cloud Config has facilities to change configuration properties at runtime via the Spring Cloud Bus and using a Cloud Config Server. The configuration or .properties or .yml files are "externalized" from the Spring app and instead retrieved from a Spring Cloud Config Server that the app connects to on startup. That Cloud Config Server retrieves the appropriate configuration .properties or .yml files from a GIT repo (there are other storage solutions, but GIT is the most common). You can then change configuration at runtime by changing the contents of the GIT repo's configuration files--The Cloud Config Server broadcasts the changes to any Client Spring applications via the Spring Cloud Bus, and those applications' configuration is updated without needing a restart of the app. You can find a working simple example here: https://github.com/ldojo/spring-cloud-config-examples