Altostratusirule replace and modify uri and response
Hello everyone,
I have a problem with the irule that I've develop to the response from the server.
To put them in context the user access to the app with three different uri:
There are three different pools with two pool members for each.
When the servers receives the resquests is more like:
first sever http://example.com/Novaris with the same name for the path.
My irule is like this:
when HTTP_REQUEST {
STREAM::disable
# Check the requested path (set to lowercase)
# -glob: allow string pattern matching
switch -glob -- [string tolower [HTTP::uri]] {
"/ris1" {
log local0. "Matched pool 1 paths for [HTTP::uri]"
set uri [ string map -nocase { "/ris1" "/Novaris"} [HTTP::uri] ]
HTTP::uri $uri
HTTP::header remove "Accept-Encoding"
pool P1
}
"/ris2" {
log local0. "Matched pool 1 paths for [HTTP::uri]"
set uri [ string map -nocase { "/ris2" "/Novaris"} [HTTP::uri] ]
HTTP::uri $uri
HTTP::header remove "Accept-Encoding"
pool P2
}
"/ris3" {
log local0. "Matched pool 1 paths for [HTTP::uri]"
set uri [ string map -nocase { "/ris3" "/Novaris"} [HTTP::uri] ]
HTTP::uri $uri
HTTP::header remove "Accept-Encoding"
pool P3
}
default {
log local0. "Hit default for [HTTP::uri]"
HTTP::header remove "Accept-Encoding"
persist cookie insert "Redimed"
pool Pool_demobank
}
}
}
when HTTP_RESPONSE {
STREAM::disable
if {([HTTP::status] == 200) && ([HTTP::header value Content-Type] contains "text") } {
STREAM::expression { @http@https@ @/Novaris@/ris1@ @/Novaris@/ris2@ @/Novaris@/ris3@ }
STREAM::enable
}
}
My problem is in the response.
When the server response because the payload don't show the image so I fix with the stream:expression but with the other two not. Because the path have the same name there is another way to map this problem o I need to explain to the development team to modify the name of the path with each pool.
Thank you if anyone can help me.
If I understand you correctly, you need to alter the stream expression in your HTTP_RESPONSE event, based either on the pool that was selected or the URI you received, during the HTTP_REQUEST event.
Note that you may need to capture that in a variable in the HTTP_REQUEST event, and check the variable in the HTTP_RESPONSE event, because you might only be able to use certain API functions inside certain events.
Something like:
when HTTP_REQUEST {
set orig_uri [HTTP::uri]
# the rest of your logic
}
when HTTP_RESPONSE {
STREAM::disable
if {([HTTP::status] == 200) && ([HTTP::header value Content-Type] contains "text") } {
switch -glob -- [string tolower $orig_uri] {
"/ris1*" {
STREAM::expression {@http:@https:@ @/[Nn]ovaris@/ris1@}
}
"/ris2*" {
STREAM::expression {@http:@https:@ @/[Nn]ovaris@/ris2@}
}
"/ris3*" {
STREAM::expression {@http:@https:@ @/[Nn]ovaris@/ris3@}
}
}
STREAM::enable
}
}(There are other optimisations that might shorten this, but you should get the gist)
Note that I have also changed the expression for your http/https rewrite to http:/https: (note the colon), so that any https:// URI returned by the downstream server is not rewritten to httpss://.
You may also need to handle a case-sensitive response back from the downstream server (I presume you would need to rewrite /Novaris or /novaris for instance). To that end, you may need to make your stream search expression something like...
@/[Nn][Oo][Vv][Aa][Rr][Ii][Ss]@/ris1@
...so it handles upper- and lower-case.
Hi,
If the stream expression string starts or ends with space, it won't work.
It looks neater with space, but it shouldn't. 🙂# This will work STREAM::expression {@IE@Apache@ @Windows@Linux@} # and this will work STREAM::expression [list "@IE@Apache" "@Windows@Linux@"] # but this will NOT work-- notice the space between the '{' and the '@' STREAM::expression { @IE@Apache@ @Windows@Linux@ }REF: https://clouddocs.f5.com/api/irules/STREAM__expression.html
