Forum Discussion

Nimbostratus

Apr 01, 2023

Standard irule that can be used for multiple urls

Here is a usecase I have and I am trying to find a solution for it. ABCD.com/app1/anything Translated to: app1.internaldomain.com/everything Abcd.com/app2/api/hello App2.internaldomain.com/API/he...

Nimbostratus

Thank you CA_Valli.
I think this works when we are hardcoding the app1 in the condition.

I was wondering if this irule can be agnostic in a way it can be used for any number of Virtual servers.

Example:

testurl.externaldomain.com/app1/api/hello

testurl.extenaldomain.com/app2/api/bye

testdifferenturl.externaldomain.com/app4/api/test/*/*

so all these urls will have one virutal server which should have a common generalized irule.

testurl.externaldomain.com/app1dev/api/hello - it would be a redirect the customer still sees the same url in the browser.

set hostname: app1dev.internaldomain.com/api/hello

set pool : testurl.externaldomain.com_app1dev

testurl.externaldomain.com/app1qa/api/getemployeedetails - it would be a redirect the customer still sees the same url in the browser.

set hostname: app1qa.internaldomain.com/api/getemployeedetails

set pool : testurl.externaldomain.com_app1qa

the way we formulated the url is

externaldomain/appname/whateverapitheappsupports.
appname needs to be appended with internaldomain and the whateverapitheappsupports need to the URI.
whateverapitheappsupports - this can be just /api/hello or /api/employee/1234 or /swagger anything that comes after the app name.

Please let me know if the above example is clear or if i am not explaining it properly.

CA_Valli

MVP

Apr 04, 2023

It's possible, indeed.
I'm struggling a bit to see the logic you want to implement based on naming conventions, I've developed the following, feel free to adjust it as you require.

when HTTP_REQUEST {

  set hostname [string tolower [HTTP::host]]

  #This IF exists to implement hostname exclusion 
#  if {[class match $hostname eq datagroup_irule_exlcusion]}{ return }

  set uri [HTTP::uri]
  set poolname "testurl.externaldomain.com_"
  set newhost ".internaldomain.com"

  set application [substr $uri 1 "/"] ; log local0. "application is $application"
  set newuri [string trimleft $uri "/$application"]
  set poolname "$poolname$application" ; log local0. "pool $poolname"
  set newhost "$application$newhost" ; log local0. "host $newhost"

  # do you need a redirect (1), or a rewrite (2)? 
  
  # (1) client will see the redirect
#  HTTP::redirect "http://$newhost/$newuri"
  
  # (2) rewrite is transparent to client 
#  HTTP::header replace "Host" "$newhost"
#  HTTP::uri "$newuri"
#  pool $poolname
  
}

With redirect instruction, client sees this. As you can see URL was changed to new host and URI is cropped and retained.