How do I make Spring Boot Zuul Proxy Server handle a specific request locally, instead of proxying it to some other Server?
Let's say I want to do a custom health check of Zuul Proxy Server itself through an API which should return a local response, instead of returning a proxied response from some other remote server.
What kind of route configuration is required to forward the request?
Following is what I figured out and it worked for me:
1) Create a local request handler:
Add a regular Controller/RestController with a RequestMapping in a file in Zuul proxy Server code
#RestController
public class LocalRequestHandler {
#GetMapping(path = "/status", produces = MediaType.TEXT_PLAIN_VALUE);
private static ResponseEntity<String> getServiceStatus() {
String status = "I am alive";
return ResponseEntity.ok().body(status);
}
}
2) Create a local forwarding route in the configuration file (application.properties or as the case may be) where other routes are defined. In my case, Spring Boot Zuul Proxy server is running on Jetty container with GatewaySvc as the application context.
zuul.routes.gatewaysvc.path=/GatewaySvc/status
zuul.routes.gatewaysvc.url=forward:/GatewaySvc/status
For a standalone Spring Boot, which I have not tested, you may have to remove the context path from the above configuration.
zuul.routes.gatewaysvc.path=/status
zuul.routes.gatewaysvc.url=forward:/status
Reference:
Strangulation Patterns and Local Forwards
Related
I want to achieve the following with a spring boot webflux application:
I have an endpoint api/test. I would like the same controller to be available on dynamically configured sub paths. E.g. if configured a sub-route "app" then a request to app/api/test should end up in the same controller.
To facilitate this I did the following using a RouteLocatorBuilder:
route(id = "proxy_api_test") {
host(location.host)
path("/${location.route}/api/test/**" )
filters{
filter(setPathGatewayFilter.apply(createSetPathConfig("/api/test")))
}
uri(location.uri)
}
In case of testing on localhost for example location.host would be "localhost:8080" and location.route could be "app" and location.uri would be "http://localhost:8080".
And createSetPathConfig is given as:
fun createSetPathConfig(template: String): SetPathGatewayFilterFactory.Config{
val config = SetPathGatewayFilterFactory.Config()
config.template = template
return config
}
When running the application that would work like a charm because requests to http://localhost:8080/app/api/test would be redirected to http://localhost:8080/api/test with the help of spring cloud gateway. I have chose this approach also because it could be various sub paths at the same time, so the same controller must be available from different entry paths.
Now what I see is that this does not work in unit-tests using an #Autowired val client: WebTestClient because when executing the unit-test in fact no web-server is running. Is there a way to indicate with the uri in with RouteLocatorBuilder that the request should be executed on the same host such that unit-test would also work with the same logic? Because in fact in this case I would like spring cloud gateway not to forward to another host but to just change the routes dynamically.
Our application is been deployed inside a DC/OS which is developed using
spring boot (2.0.6.RELEASE) & swagger (2.6.1).
problem we are getting is am accessing swagger via
https://api.example.com/appname/swagger-ui.html This is working fine and returning swagger UI with all our REST endpoints.
When I try to request our API through swagger this hostname is changing to https://api.example.com:80
Wrong request URL generated by swagger -
https://api.example.com:80/health
Correct request URL should be https://api.example.com/appname/health
Added screenshot actual domain names are altered.
Our Config
#SpringBootApplication
#EnableSwagger2
public class AppConfig {
public static void main(String[] args) {
SpringApplication.run(AppConfig.class, args);
}
}
I would like to understand
How the hostname is been generated for request URL?
Why it is not relative path based on the URL accessed?
How to configure this base url of swagger so that request url can be relative based on the URL used to access swagger.
You may check Springfox Swagger generating requests with port 80 for HTTPS URLS for similar issue reported
You may set the property
springfox.documentation.swagger.v2.host=api.example.com
or through config api
docket.host("your host url")
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!
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
If you would like to have on Zuul the UI(front-end) you can add the static content in resources/static folder(html, css and js files). On this way your proxy is able to render the index.html (of course you must have an index.html in static folder). O this way on http://localhost:8080 the proxy will render index.html; also you can have another paths but all these path are managed by index.html)
About routing, the Zuul only redirect the http request. http://localhost:8080/ui/. On 8080 is running the proxy (Zuul) BUT /ui is the context path of resource server. Se when you make a call on this path http://localhost:8080/ui/ the proxy will redirect to resource server and will actually make a request to http://localhost:8090/ui/
It is a difference between browser path and http request path. The browser path is managed by index.html and the http request is managed by Zuul. I don't know if I was explicit enough.
One more thing... You can have the same path (/ui) on http request and index.html and when your browser will access the http://localhost:8080/ui/ a .js file with http request method will make an http request to http://localhost:8080/ui/ and then will be redirected to http://localhost:8090/ui/ and the response from the resource server will be rendered on the page from http://localhost:8080/ui/.
I have hosted 3 microservices in PCF. One is a eureka server and the other 2 are client and service microservices. The client is supposed to call the service through a rest template call and service will return a string.
I have 1 instance each of the eureka server and the client and 2 instances of the service.
I can see both my client and service registered in the Eureka dashboard. But when i try to access the service from the client[Using a rest template call] I get - 'No instances available for the [service name]'
But if i access my service directly from browser then its works fine and returns the string. But the same URL if called from a rest template returns the exception i mentioned above.
Any suggestions will help
Did you add the #LoadBalance on restTemplate bean.
#Bean
#LoadBalanced
public RestTemplate restTemplate() {
return new RestTemplate();
}
And when calling service you have to use the service name as below.
https://SERVICENAME/restpath
I'm modifying the oauth2-vanilla sample from Springs excellent security tutorials. The oauth2-vanilla combines the Zuul Proxy and the UI into a single application. I would like to seperate the Zuul Proxy and the UI. (The Zuul Proxy should act as an API gateway and as a reverse proxy for several UIs).
When accessing the UI via the zuul proxy, it should be able to do SSO based on Oauth2 between the UI and the resource backend.
The oauth2-vanilla looks like this
Where I want to move to something like this :
I've removed the UI part from the gateway, and added a zuul route for the ui
zuul:
routes:
resource:
url: http://localhost:9000
user:
url: http://localhost:9999/uaa/user
ui:
url: http://localhost:8080
I created a new UI webapp containing the UI (Angular stuff) with an #EnableOAuth2Sso annotation.
So I'm accessing the UI via http://localhost:8888 (through the zuul proxy).
After authenticating and doing through the UI flow, I can access the /user endpoint that returns me the user. (During debugging, I see that when I access the /user endpoint that I have an HTTP Session with an OAuth2Authentication.
When I access the /resource endpoint however, the HttpSessionSecurityContextRepository cannot find a session and is unable to build a context with the OAuth2Authentication.
I've created a git repository with the modified sample.
I'm guessing there is something wrong with the gateway configuration.
I've tried changing cookie paths, changing HttpSecurity rules in the proxy but I cannot get it to work.
What I don't understand is why the UI, when accessed through the proxy is able to resolve the /user endpoint fine (with an HTTP session and a OAuth2Authentication), but it is unable to access the /resource endpoint.
Also, as the UI is now running in the /ui context, it seems that I need to have the following code in the gateway for it to load up the angular css / js files.
.antMatchers("/ui/index.html", "/ui/home.html", "ui/css/**", "/ui/js/**").permitAll().anyRequest().authenticated();
It also doesn't seem right that I need to prefix it with the zuul ui route.
Any help would be appreciated.
I was never able to get the #EnableOauthSso to work. Instead, I annotated as an #EnableResourceServer and created a security config for Zuul.
#Configuration
#EnableResourceServer
public class JwtSecurityConfig extends ResourceServerConfigurerAdapter {
#Override
public void configure(HttpSecurity http) throws Exception {
http.authorizeRequests()
.antMatchers("/oauth/**").permitAll()
.antMatchers("/**").hasAuthority("ROLE_API")
.and()
.csrf().disable();
}
}