I am using a spring-cloud discovery service in my docker-compose. All spring-boot services that are under my control register themselves on startup via "EnableDiscoveryClient".
But I have other services in my docker-compose that I run from their dockerhub images. How can I register them as well (database, ldap, ...)
Is there a way to configure eureka to look for defined components (pull) instead of the client "push"?
You would have to implement a Sidecar app and most-likely create a Docker image using a database, ldap image from the dockerhub as the starting point.
I published a blog post about this exact topic: Microservices Sidecar pattern implementation using Postgres, Spring Cloud Netflix and Docker
Related
I am going to create a kubernetes cluster to deploy all my spring boot microservices. Currently I have a spring cloud gateway server, a eureka discovery server and my back-end and front-end applications.
Do we need gateway server and discovery server if deployed on kubernetes, as these services are provided as part of cluster?
Thanks.
You are not required to use the Spring Cloud Gateway or Eureka discovery server. Kubernetes provides all basic building blocks (like Service) implemented without additional software requirements (for example with plain DNS).
If you need a more advanced setup you can integrate kubernetes API in Spring applications or use other ways to integrate. For the 90% case there is no need to do so.
I'm developing a spring-microservice architecture with following modules (see the architecture diagram below):
Configuration-server
Eureka-Server
Zuul Api Gateway
User-api(Config-Server-Client, Eureka-Client)
Stats-api(Config-Server-Client, Eureka-Client)
Auth-Service (in-progress/out of context)
It's is more of a configuration approach rather than a bug. So far everything is running fine.
For most of the configurations of core-apis, I'm loading them from config-Server.
What should be the actual or recommended way if we use config-server with Api-Gateway?
Would it be good to map(load from) the configuration of Zuul-Gateway to my Config-Server as with other core apis like User-Api and Stats-Api.
And if I did so what should be the order of starting the applications?
Like:
1. Start the Config-Server
2. Eureka Server
3. Zuul Gateway
4. Core-Apis
Thanks :)
I have build a similar architecture for testing purpose. You can find in the link below:
https://github.com/rshtishi/payroll
The order I use to start the services is like below:
Configuration Server (Spring Cloud Config Server) is always the first start. Here are the configuration for all the services.
Eureka Server, is responsible for registering all services.
After starting the service above, you can start whatever you wish api-services or zuul gateway server. Zuul gateway server will access the api services through eureka. So it doesn't matter the order.
I am setting up the Spring-boot microservices with the cluster bi-direction Pivotal cloud cache.
I have set up the bi-directional cluster in Pivotal Cloud, I have a list of locators with ports.
I have already some online docs.
https://github.com/pivotal-cf/PCC-Sample-App-PizzaStore
But couldn't understand the on which configuration the spring boot app will know to connect.
I am looking for some tutorial or some reference where I can have spring boot app linked up with the PCC(gemfire)
The way you configure a app running in PCF (Pivotal Cloud Foundry) to talk to a PCC (Pivotal Cloud Cache) service instance is by binding the app to that service instance. You can bind it either by running the cf bind command or by adding the service name in the app`s manifest.yml, something like the below
path: build/libs/cloudcache-pizza-store-1.0.0-SNAPSHOT.jar
services:
- dev-service-instance
I hope you are using Spring Boot for Apache Geode & Pivotal GemFire (SBDG) in your app, if not I recommend you to use it as it makes connecting to PCC service instance extremely easy. SBDG has the logic to extract credentials, hostname:ports needed to connect to a service instance.
You as a app developer just need to
Create the service instance.
Bind your app to the service instance.
The boilerplate code for configuring credentials, hostnames, ips are handled by SBDG.
When you deploy an application in Cloud Foundry, (or Pivotal Cloud), you need to bind it to one or more services. Service details are then automatically exposed to the app via the VCAP_SERVICES environment variable. In the case of PCC this will include the name and port of the locator. By adding the spring-geode-starter (or spring-gemfire-starter) jar to the application it will automatically process the VCAP_SERVICES value and extract the necessary endpoint information in order to connect to the cluster.
Furthermore, if security is enabled on your PCC instance, you will also need to have created a service key. As with the locator details, the necessary credentials will be exposed via VCAP_SERVICES and the starter jar will automatically process and configure them.
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 creating a simple project in microservices using spring boot and netflix OSS to get my hands dirty. I have created two services
config service which has to register itself in discovery(eureka)
service.
discovery service which requires config service to be running to get its configuration.
Now when I am starting these services, both services fails due to inter dependency. What are the best practices resolve this issue and which one to start first.
PS:- I know I am creating circular dependency, But what is the way to deal with situation like this where I want to keep eureka configuration also with the config server
Thanks
I believe that you can find the answer for your question in the official spring cloud config server documentation:
Here: http://cloud.spring.io/spring-cloud-config/spring-cloud-config.html#_spring_cloud_config_client
Basically you have to choose between a "Config First Bootstrap" or "Discovery First Bootstrap".
From the docs:
"If you are using a `DiscoveryClient implementation, such as Spring Cloud Netflix and Eureka Service Discovery or Spring Cloud Consul (Spring Cloud Zookeeper does not support this yet), then you can have the Config Server register with the Discovery Service if you want to, but in the default "Config First" mode, clients won’t be able to take advantage of the registration.
If you prefer to use DiscoveryClient to locate the Config Server, you can do that by setting spring.cloud.config.discovery.enabled=true (default "false"). The net result of that is that client apps all need a bootstrap.yml (or an environment variable) with the appropriate discovery configuration. (...)"