Docs says that Eureka client can be integrated into Spring Application very simply, just add one annotation to your configuration class and several properties into your application.properties. But says nothing about manual startup/shutdown of client. I want to customize behaviour of that client (or delay its init, because (wow!) entire logic lays in client's constructor): instead of background registration via Spring Boot's auto-configuration, client must register in Eureka server when application (with Eureka client) itself gets initialized, and only after that application will be able to gather metadata, put it to Eureka client's metadataMap and then start registration process in Eureka server. Of course, I can take ApplicationInfoManager instance and call registerAppMetadata, but what do if dependant application (also registered in the server) requires that applications must register with required metadata?
you could configure a health page and point the health check to it - https://cloud.spring.io/spring-cloud-netflix/multi/multi__service_discovery_eureka_clients.html#_status_page_and_health_indicator
Related
I've just been playing around with Spring Boot and developed a small Spring Cloud Streams app which basically acts as a destination for incoming messages through a queue.
However, I wanted to expose a health check endpoint so that I can verify if the service is up and running.
Until now, spring.main.web-application-type has been none. However, tu run actuator I must have that on.
I want to think that having the previously mentioned property to none didn't make the service exposed to the outside world and now that it has been enabled I must check and prevent some kind of accesses?
Are there any security concerns I must check now?
Is there a way I can define the port for the management URLs (not the management.server.port) so that spring boot admin can identify the actuator URLs from the spring boot app for monitoring?
I'm running the spring boot app in a docker container and it's externally exposed on a different port using the Kubernetes NodePort.
If you are using service discovery for application lookup you could define the exposed management port in instance metadata. This metadata is used to build up the management URL.
More details documented here:
http://codecentric.github.io/spring-boot-admin/current/#spring-cloud-discovery-support
Handling is done in de.codecentric.boot.admin.server.cloud.discovery.DefaultServiceInstanceConverter
Example for Eureka:
eureka.instance.metadata-map.management.port=[K8S-EXPOSED-PORT]
If you are using Service Discovery, take a look into DefaultServiceInstanceConverter, try specifying the management.port property.
If you are not using Service Discovery, then take a look into de.codecentric.boot.admin.server.domain.values.Registration, you might need to use the builder apis to register your application correctly (try to set managementUrl properly). Note, you will need to do this in your client application (the one which is being monitored).
I am developing a microservice, using Spring Boot, that exposes REST Endpoint. Because of scalability, I have to run multiple instances of this services on a different port. What will be the configurations for the applications so that it can register with eureka and requests are load balanced? I am using Spring cloud config, Eureka server and zuul.
Attaching following entries in the client properties file will do the trick. This is for Spring cloud config dalston
eureka.instance.instanceId=${spring.application.name}:${spring.application.instance_id:${random.value}}
I guess you meant to register with Eureka instead of Config server.
To register multiple instances that might be running in the same host but listening on a different port you would need to set eureka.instance.metadataMap.instanceId to a unique value maybe using:
eureka.instance.metadataMap.instanceId=${spring.application.name}:${random.int}
I have spring web application (not spring boot) running in AWS. I am trying to create centralized configuration server. How to refresh the spring-cloud-client after the changing the properties? As per tutorial
Actuator endpoint by sending an empty HTTP POST to the client’s refresh endpoint, http://localhost:8080/refresh, and then confirm it worked by reviewing the http://localhost:8080/message endpoint.
But my aws Ec2 instances are behind the loadbalancer so i can't invoke the client url. I didn't understand the netflix Eureka and Ribbon much but it seems like adding another level of load balancer in the client side. I don't like this approach. Just to change a property i don't want to make the existing project unnecessarily complex. Is there any other way? or Am I misunderstood Eureka/Ribbon usage?
I have looked at the spring-cloud-config-client-without-spring-boot, spring-cloud-config-client-without-auto-configuration none of them have answer. First thread was answered in 2015. Wondering is there any update?
To get the configuration properties from a config server. You can do a http request. Example:
From the documentation we can see:
/{application}/{profile}[/{label}]
/{application}-{profile}.yml <- example
/{label}/{application}-{profile}.yml
/{application}-{profile}.properties
/{label}/{application}-{profile}.properties
So if you would do a request to http://localhost:8080/applicationName-activeProfile.yml you would receive the properties in .yml format for the application with that name and active profile. Spring boot config clients would automatically provide these values but you will have to provide em manually.
You don't need Eureka/Ribbon for this to work, it's a separate component.
More info: http://cloud.spring.io/spring-cloud-static/spring-cloud.html#_spring_cloud_config
Maybe you could even use spring-cloud-config but I'm not sure what extra configuration is needed without spring-boot.
https://cloud.spring.io/spring-cloud-config/
I have serveral microservices communicating with each other.
For general configuration I use Spring Cloud Config which works well.
Some of the services need to access database resources of a legacy system. So they need to know where the database (databases in a multi-tenant environment) is located and which credentials to use.
Using Spring Cloud Config I see two possibilities:
application.properties: This would expose the db settings to all services. That´s no option.
my-crazy-service.properties: This would work fine but I would have to configure any service which needs db access. Doesn´t scale well.
So my idea is to implement another microservice which is responsible for any connection infomation. This service exposes a rest endpoint using spring-data-rest.
In case Service A wants to use the legacy db it can call the new service and ask for the required data.
Now I wonder when the best time is to request the connection info from the remote service.
On startup of each microservice? Where should such startup code be located?
In general where should initialization stuff be done?