Spring Cloud: default redirecting from Gateway to UI

I'm new to microservices and Spring Boot. I have a few Spring Cloud microservices with a Zuul gateway running on port 8080.

   browser
      |
      |
    gateway   (:8080)
     /   \
    /     \
   /       \
resource   UI (:8090)

There is a UI microservice on port 8090, which has a controller with a method inside, returning index.html.

I configured Zuul routing like this for UI (I'm using Eureka too):

zuul:
  routes:
    ui:
      path: /ui/**
      serviceId: myproject.service.ui
      stripPrefix: false
      sensitiveHeaders:

If I call http://localhost:8080/ui/ everything works fine and I see rendering of my index.html.

Is it possible to configure Spring Cloud in some way to make the following flow work: calling http://localhost:8080/ redirects us to controller of UI microservice, which returns index.html?

So the idea is to open UI from the root of my site.

Thanks in advance!

Solution

Finally, I've made my code work! Thanks to @pan for mentioning Zuul Routing on Root Path question and @RzvRazvan for revealing about how Zuul routing works.

I've just added controller to Zuul routed Gateway microservice with one endpoint to redirect from root http://localhost:8080/ to http://localhost:8080/ui/:

@Controller
public class GateController {    
    @GetMapping(value = "/")
    public String redirect() {
        return "forward:/ui/";
    }    
}

Zuul properties for redirecting from Gateway microservice on port 8080 as http://localhost:8080/ui/ to UI microservice, which implemented as a separate Spring Boot application on port 8090 as http://localhost:8090/ui/:

zuul:
  routes:
    ui:
      path: /ui/**
      serviceId: myproject.service.ui
      stripPrefix: false
      sensitiveHeaders:

UI microservice's properties:

server:
  port: 8090
  servlet:
     contextPath: /ui

Eventually, this call http://localhost:8080/ redirects us to controller of UI microservice, which returns view index.html:

@Controller
public class UiController {
    @GetMapping(value = "/")
    public String index() {
        return "index.html";
    }
}

Actually, I had another problem with rendering static content in such architecture, but it was connected with configuration of my front-end, which I develop using Vue.js framework. I will describe it here in a few sentences, in case it might be helpful for someone.

I have the following folders structure of UI microservice:

myproject.service.ui
    └───src/main/resources
        └───public
            |───static
            |    ├───css
            |    └───js
            └───index.html

All content of public folder is generated by npm run build task from webpack and vue.js. First time, I called my http://localhost:8080/ I got 200 OK for index.html and 404 for all other static resources, because they was called like this:

http:\\localhost:8080\static\js\some.js

So it was configured wrong public path for static assets in webpack. I changed it in config\index.js:

module.exports = {
  ...
  build: {
    ...
    assetsPublicPath: '/ui/',
    ...
  }
...
}

And static assets became to be called properly. e.g.:

http:\\localhost:8080\ui\static\js\some.js