Allow filtering of services in discovery client route locator

[pravinkumarb84]

Do we have implementation for ignoredServices and ignoredPatterns in gateway as in zuul?

[ryanjbaxter]

The gateway isnt proactive like Zuul is and automatically creates routes based on service discovery they have to be explicitly configured (as far as I know). Can you provide an example of where this would be necessary?

[spencergibb]

I'd rather have some metadata that is set that would tell the integration to setup a route (edge=true) or something. @ryanjbaxter internal only services come to mind.

[spencergibb]

You can now specify an expression that works on the ServiceInstace to test if the particular service should be included in as a route.

Setting spring.cloud.gateway.discovery.locator.include-expression=metadata['edge'] == 'true' will test for a metadata field named edge whose value is true.

[gewure]

The gateway isnt proactive like Zuul is and automatically creates routes based on service discovery they have to be explicitly configured (as far as I know). Can you provide an example of where this would be necessary?

In my Zoo i have some services that should be gatewayed' and others that don't and should be ingnored-services as in zuul. How to achieve a functionality like in zuul?

[ryanjbaxter]

You can now specify an expression that works on the ServiceInstace to test if the particular service should be included in as a route.

Setting spring.cloud.gateway.discovery.locator.include-expression=metadata['edge'] == 'true' will test for a metadata field named edge whose value is true.

[gewure]

You can now specify an expression that works on the ServiceInstace to test if the particular service should be included in as a route.

Setting spring.cloud.gateway.discovery.locator.include-expression=metadata['edge'] == 'true' will test for a metadata field named edge whose value is true.

im sorry, i don't get it.
e.g. if i have 3 services, eureka name: "backend", "stream", "oldbackend" and i want to include discovery of backend and stream, but not of oldbackend.. i would set:

spring.cloud.gateway.discovery.locator.include-expression=metadata['backend','stream'] == 'true'

?

[spencergibb]

No, you would include a bit of metadata in the discovery configuration of each service that you want in gateway such as 'edge=true'. Then gateway will only include those.

[gewure]

No, you would include a bit of metadata in the discovery configuration of each service that you want in gateway such as 'edge=true'. Then gateway will only include those.

i see.

.. so for my "backend" and "stream" service i'd do

spring:
  cloud:
    discovery:
      client:
        simple:
          local:
            metadata:
              isongateway: true

in the bootstrap.yml of the backend and stream service and then check on the gateway via spring.cloud.gateway.discovery.locator.include-expression=metadata['isongateway']=='true' --- and all other services, though still discovered by eureka, are not reachable via gateway.

[gewure]

@spencergibb @ryanjbaxter this works nice, thanks for support. keep up the good work!

[xiaoshao]

@spencergibb @ryanjbaxter What is about the IgnoredPatterns? There is some rest interface is internal in some service.

[spencergibb]

@xiaoshao if you have read thru this issue, you'll see that is not necessary and there is no ignore services in gateway

[Alos]

@spencergibb @ryanjbaxter do you know if the spring.cloud.gateway.discovery.locator.include-expression works for all DiscoveryClient implementations? i.e Would Spring Cloud Kubernetes discovery work with this?

[spencergibb]

It works on the API but the implementation, so yes, it should work.

[Alos]

I'm having issues getting it to work. I've configured the following in the gateway:

  cloud:
    gateway:
      discovery:
        locator:
          enabled: true
          url-expression: "'http://'+serviceId+':8080'"
          include-expression: metadata['edge']=='true'

Does that look OK to you? Is there a bean or class that gets the metadata that I can debug or turn on logging to confirm that the DiscoverClient passes the metadata to the gateway locator? I guess its the DiscoveryClientRouteDefinitionLocator?

[spencergibb]

Please open a new issue and we will continue it there