My Services are being registered on jhipster-registry. As can be seen below:
As you can see, Canoja service and Gateway are registered in my service registry.
And as per the documentation:
The gateway will automatically proxy all requests to the microservices, using their application name: for example, when microservices app1 is registered, it is available on the gateway on the /services/app1 URL.
I was expecting the gateway to pull my service APIs automatically. But, my APIs are not available in the gateway:
I had the same problem, apparently the problem was with the names of the registered microservices (they were too long).
I was using a generated gateway that was generated using JHipster 7.9.3, and a registry version 7.4.0, and all the microservices were created using jhipster 7.9.3 as well.
Sadly, i cannot provide any logs whatsoever because the gateway was displaying no logs whatsoever, just the fact that it fails to route because no instance of the called service was found.
TLDR: try to make each service name between 3 to 8 characters and no special characters.
Related
TLDR : Is it okay to use controller class in spring gateway instead of routing in config class? I want to take data from one service and then pass it the response from that service to another.
I used spring cloud gateway to create an api gateway. I have several services that need to communicate. I currently only use the gateway for routing to the first service and then the first service is going to talk to other service by itself. But this is becoming troublesome now that I have a lot of services.
I am trying to deploy a simple microservice application (Spring boot) in GAE. The application has 3 services -
1. Discovery Service
2. Spring Cloud Gateway
3. Customer service
I am trying to call an API through API gateway. This works fine in local machine but getting 404 in GAE hosted application.
The URL I am using is - https://Gateway-url/customer-service/version
And corresponding YAML config is :
spring:
cloud:
gateway:
routes:
-id: customer-service
uri: https://XXXXXX.customer-service.appspot.com/
predicates:
- Path=/customer-service/**
filters:
- StripPrefix=1
The URI configured in above code snippet is - target URL of GAE service.
So When I hit the https://Gateway-url/customer-service/version url in browser, I am getting 404 error but it works if I hit the direct url https://customer-service-url/version
When I changed the API Gateway configuration in the local environment, (change uri to cloud based service uri), the issue is reproducible. So I am thinking that Gateway is not able to route the requests to App Engine Service target URL.
How can I fix this problem?
I think the problem is the url that you are using in the configuration file to route your requests.
According to google cloud documentation, to call from one service to another you should use a endpoint like this
https://VERSION_ID-dot-SERVICE_ID-dot-PROJECT_ID.REGION_ID.r.appspot.com
As yo can see here
https://cloud.google.com/appengine/docs/standard/java/communicating-between-services
And it seems that the url that you are using doesn't fit int this.
Anyway I think that in a serverless environment such as app engine the best option to perform service discovery and to route requests via gateway is using the services provided by google. In case of service discovery it is done automatically and if you want a gateway you can use google cloud endpoints that have a greate integration with app engine. Because this is the gateway intended to use with these applications
The setup:
I have a set of Spring Boot based microservices that are fronted by Spring Cloud Gateway, meaning every request that comes from UI or external API client first comes to Spring Cloud Gateway and is then forwarded to appropriate microservice.
The routes are configured in Consul, and Spring Cloud Gateway communicates with Consul to get the routes accordingly.
Requirement:
There is a need of some microservices communicating with each other with REST APIs. I would prefer this communication to happen via the Spring Cloud Gateway as well. This will help in reducing multiple services going to Consul for getting other service's details.
This means every service should know Gateway's detail at least. And there can be multiple instances of Gateways as well. How is this dealt with in bigger architectures?
Any example that I look up contains one service using Consul, or Gateway using the consul with one microservice. Couldn't understand how to extrapolate that design to a bigger system.
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 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.