I have a simple Zuul app that has a single route in the application.yml to route to my microservice. It's working.
However, what I'm looking for is a more dynamic solution where I can wire up routes dynamically, either through code or perhaps by POSTing to some Zuul endpoints during a build (possibly by using springfox and a swagger definition from microservices). I could not find an API for Zuul.
I'm somewhat aware of Eureka and that seems like a solution to abstract away the routing by doing discovery. However, I'm curious if there's a solution without introducing Eureka. If there's a way to wire up these routes in Zuul during a build vs. having to edit the application.yml every time.
Thanks in advance.
If you go for Eureka this will actually work ootb. Zuul as packaged in spring cloud will automatically expose every service using its name. So if you register a service called users in Eureka, Zuul will automatically create a route /users forwarding to the instances by default. That will only allow simple url structures but should solve your problem.
Please see the official documentation for details:
By convention, a service with the ID "users", will receive requests from the proxy located at /users (with the prefix stripped). The proxy uses Ribbon to locate an instance to forward to via discovery, and all requests are executed in a hystrix command, …
I'm actually editing a blog post about this exact topic (Routing and Filtering using Spring Cloud Zuul Server) but the source code has been available and working for some time now. Feel free to use it as a reference:
https://bitbucket.org/asimio/zuulserver
https://bitbucket.org/asimio/discoveryserver (in case routes are configured with serviceIds)
https://bitbucket.org/asimio/demo-config-properties/src (Zuul-Server-refreshable.yml where routes are dynamically updated).
Look at the refreshable Spring profile settings. This Zuul setup works with both, hard-coding routes url or discovered using Eureka.
It also acting as a Spring Cloud Config client so that routes could be dynamically updated via Git, which is also covered in another blog post: Refreshable Configuration using Spring Cloud Config Server, Spring Cloud Bus, RabbitMQ and Git.
Related
I know there is a similar kind of question exist but if works only for glassfish server.
Listing all deployed rest endpoints (spring-boot, jersey)
Is it possible to list all my configured rest-endpoints with spring boot? The actuator lists all existing paths on startup, I want something similar for my custom services, so I can check on startup if all paths are configured correctly and use this info for client calls.
How do I do this? I use #Path/#GET annotations on my service beans and register them via ResourceConfig#registerClasses.
Is there a way to query the Config for all Paths?
Update2: I want to have something like
GET /rest/mycontroller/info
POST /res/mycontroller/update
...
In my opinion, you are already using the right tool (actuator) to answer to your request.
Actuator gives you all the rest method running and you can configure it on your own, by disabling/enabling specific endpoints
If you have a look on the documentationprobably it can help you.
In any case, the default configuration of actuator display the endpoints (built-in in Intellij for your development).
I am trying to build a simple application with microservices architecture.
Below are the details about 3 microservices I have created.
1] Customer.
database: mongodb
server : embeded tomcat server.
port : 8081
2] vendor.
database: mongodb
server : embeded tomcat server.
port : 8082
3] product.
database: mongodb
server : embeded tomcat server.
port : 8083
All the 3 micros runs on an embeded tomcat server.
Now I want to create a common gateway for all these micros [API gateway].
which help me to route my request based on the request I get for example:-
for example if I get a request of http://hostname:port_of_gateway/customer.
on reading this I need to route the request tom my customer micro and fetch its response and send it back to client.
Which of the spring tool I can use to achieve this?
Because your requirements are quite simple you can implement such a gateway by yourself. Here's an example.
But if you really want to use some Spring solution you can try to use Spring Cloud Netflix which is a part of Spring Cloud umbrella project. It includes router and filter features which in turn based on Netflix Zuul gateway service.
Note that this is not a complete standalone application but a library. Therefore you still should create another microservice that would act as API gateway in your application. To make it a gateway you should just add #EnableZuulProxy annotation to the same class that has #SrpingBootApplication annotation. You can find a very good example here.
Please also note that you should somehow inform the gateway about your microservices' addresses for redirection. It can be done in two general ways:
By statically defining the addresses in gateway microservice's configuration;
By applying service discovery pattern in conjunction with e.g. Netflix Eureka service registry.
The 1st approach is easy and straightforward but is not very well for large number of microservices and/or when microservices' locations can change dynamically (e.g. due to auto-scaling).
The 2nd approach requires additional component - service registry - and needs modification of other microservices (to let them register themselves in the registry). This is quite more complicated approach but is the only possible in case of complex architecture. Simple yet expressive example can be found in the same article.
UPDATE (January'19)
As of December 2018 the Spring Cloud team announced that almost all Netflix components in Spring Cloud (except Eureka) entered maintenance mode. It means that for the next year they won't receive any feature updates (only bugs and security fixes).
There are replacements for all the affected components, including Netflix Zuul aforementioned above. So please consider using Spring Cloud Gateway instead of it in new projects.
I have two machines (with same application) register to eureka server.
all requests to these services are through zuul proxy.
my application.properties of my backend services is:
spring.application.name=core
my application.properties of my zuul proxy is:
zuul.sensitiveHeaders=Set-Cookie
zuul.routes.address.path=/to-address/**
zuul.routes.address.url=http://localhost:8888
zuul.routes.service.path=/by-service/**
zuul.routes.service.url=CORE
I have two questions:
All three request below are working, which one should I use?
What is the difference with upper case and lower case?
http://localhost:9090/api/by-service/customer/1
http://localhost:9090/api/core/customer/1
http://localhost:9090/api/CORE/customer/1
When I call the service in the following way:
http://localhost:9090/api/to-address/customer/1
I noticed that a new session is being created by my core server, which force my user to login again. Any idea why?
As you can see it's the same method (same filter, same application...) with just a routing difference.
you need to use req.getRequestedSessionId() instead of req.getSession().getId().
I am trying to route existing services via Spring cloud Netflix Zuul.
I have an existing service available at below url,
http://localhost:3080/query-service/getquery/1
Out of the box, with zuul I can route to the service as below,
localhost:9000/queryservice-id/queryservice/getquery/1, with "queryservice-id" as the service-id of the service when it is registered in Service Registry. The zuul port is 9000.
I do not want to change the context path and service path information when accessing the service via ZUUL.
With ZUUL, I want to access the service as below,
http://localhost:9000/query-service/getquery/1
I do want to prefix with the "serviceId". This is because I do not want to impact any existing clients of the service. Only the host and port changes, without serviceId.
I was able to accomplish it as below with ZUUL Configuration,
zuul:
routes:
query-service:
path: /query-service/**
serviceId: query-service
stripPrefix: false
With the above configuration, I am able to only use the zuul host and port, the other service specific information remains as before. Seems like stripPrefix is helping in routing without the serviceId.
But, I have a lot of services and will be adding more services too.
For every such service, I do not want to be adding a rule like that to ZUUL configuration which will mean rebuilding and recycling the ZUUL Service.
I feel there should be a simpler and better way to accomplish this, without a big effort, because the change I want to do is common to all services
Is there a way to making this change common for alll the services I want
to be routed via ZUUL.
Thanks,
As checked with the Spring Cloud Netflix team this is recommended approach.
https://github.com/spring-cloud/spring-cloud-netflix/issues/1549
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/