Increasing Gateway Timeout for Ingress Resource

There is a use case in register service for which we need to have the request timeout in Application Gateway to be increased from the default value of 30 seconds to 60 seconds

Now for some context on this need, there is create subscription API in the register service which goes and creates new Event Grid subscriptions on the Event grid topics, now this API is synchronous in nature so it usually takes longer than 30 seconds for the backend server to respond back to the gateway which ultimately results in 504 timeout errors

Currently from what I have explored we can change the request timeout settings at the ingress resource level by adding appropriate annotation which is documented here. This method has been validated in a developer instance.

Now the concern with this approach is that this timeout setting will then be applicable to all the services.

Questions

• Is there a way to enable this setting for only register service, because this seems a valid use case since down the line for some other service we might need to tweak similar gateway settings and it will easier to change at spec/service level than at ingress?

• Are there any concerns on increasing the timeout for all services?