3 scenario 301 redirection problem

This should all be possible within the same iRule. I would take a look at some of the native URI parsing commands to start with and avoid regexes if at all possible.

 

 

http://devcentral.f5.com/wiki/default.aspx/iRules/http__uri

 

http://devcentral.f5.com/wiki/default.aspx/iRules/http__path

 

http://devcentral.f5.com/wiki/default.aspx/iRules/uri

 

 

Here is one example we discussed recently:

 

http://devcentral.f5.com/Community/GroupDetails/tabid/1082223/asg/50/afv/topic/aft/1177132/aff/5/showtab/groupforums/Default.aspx

 

 

If you have a lot of URIs to all redirect to the same page (or generally take the same action), you could add them to a string datagroup and then use the class (v10) or matchclass (v9) commands to check the requested URI against the list. If you're app is case-insensitive, set the URI and the strings in the datagroup to lower case using 'string tolower "string"' before doing the class lookup.

 

 

http://devcentral.f5.com/wiki/default.aspx/iRules/class

 

http://devcentral.f5.com/wiki/default.aspx/iRules/matchclass

 

 

Keep in mind that the values for most HTTP:: commands are cached within the same event and event priority. So if you log the value, change it and then try to log it again, the logging won't show the change even though it's been made.

 

 

If you get stuck, reply here with what you've tried and what's not working.

 

 

Aaron

Here is my first iRule made possible via all of the great examples I found in the forum.

 

 

when RULE_INIT {

 

Debug off (0), Errors-only(1), On(2) or Verbose(3)

 

set ::debug 0

 

}

 

when HTTP_REQUEST {

 

 

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

 

set uri [string tolower [HTTP::uri]]

 

set A [HTTP::host][HTTP::uri]

 

 

only test urls that need to be redirected.

 

if { [class match $uri contains jm_urls] } {

 

 

print the incoming uri so we can compare before/after results in the ltm log:

 

if { $::debug>=2 } { log local0. " iRule TEST input before we mess with it: $H$uri "}

 

 

Case 1: if I can match a target uri, substitue the first part, plus everything after the

 

old 22 character length target uri that I"m replacing.

 

if { $uri contains "/bn/community/jm/blog/" } {

 

set puri [substr $uri 22 ";"]

 

HTTP::respond 301 Location "http://$H/bn/blogs/dl/$puri"

 

if { $::debug>=2 } { log local0. " Test Case 1 satisfied "

 

set A "http://$H/bn/blogs/dl/$puri"

 

}

 

Case 2: now lets chase down document numbers, and redirect if we find a target:

 

 

} elseif { $uri contains "/bn/docs/doc-" } {

 

set puri [substr $uri 13 ";"]

 

HTTP::respond 301 Location "http://$H/jmredirect/doc/$puri"

 

if { $::debug>=2 } { log local0. " Test Case 2.1 satisfied "

 

set A "http://$H/jmredirect/doc/$puri"

 

}

 

} elseif { $uri contains "/bn/docs/" } {

 

set puri [substr $uri 9 ";"]

 

HTTP::respond 301 Location "http://$H/jmredirect/doc/$puri"

 

if { $::debug>=2 } { log local0. " Test Case 2.2 satisfied "

 

set A "http://$H/jmredirect/doc/$puri"

 

}

 

Case 3: lets redirect the door page. redirects. Third verse, same as the first...

 

 

} elseif { $uri ends_with "/bn/community/jm/" } {

 

HTTP::respond 301 Location "http://$H/dl/"

 

if { $::debug>=2 } { log local0. " Test Case 3 satisfied "

 

set A "http://$H/dl/"

 

}

 

Case 4: lets redirect everything else to the /dl/downloadinvalid.aspx page.

 

 

} else {

 

HTTP::respond 301 Location "http://$H/dl/downloadinvalid.aspx"

 

if { $::debug>=2 } { log local0. " Test Case 4 satisfied "

 

set A "http://$H/dl/downloadinvalid.aspx"

 

}

 

}

 

show me what the rewritten uri looks like in the logs. log file should have three lines of

 

code-generated log messages each time this iRule fires:

 

 

" iRule TEST input before we mess with it: "

 

" Test Case satisfied "

 

" iRule TEST output: "

 

 

 

if { $::debug>=2 } {log local0. " iRule TEST output: $A " }

 

 

}

 

}

 

 

Any feedback would be welcome.

 

 

Thanks,

 

 

Troy

Hi Troy,

 

 

That looks good. Does the rule work for your requirements?

 

 

As you're comparing the same thing in all of the if/elseif/.../else statements, you could replace them with a switch statement. But that's really a matter of preference.

 

 

Aaron

It is working well in the QA environment so we will see how the PROD rollout goes....;-) When I added the 4th case I thought about using a switch statement instead. Since I am ahead of the web developers I will probably give that a try since we will be moving more areas in the near future.

 

 

I do have a concern with Case 2, I am passing the parameter to a web page that will do the look up and send a redirect to the actual page. Is there a way that I could issue the http request to the redirect page and then return the actual 301 url redirect to the client to avoid a double 301 redirect?

 

 

The links you sent were very helpful.

 

 

Thanks,

 

 

Troy

 

Switch is definitely more efficient. It's also, in my opinion, far more readable. We tend to encourage folks to go that route if they're comfortable with it. ;)

 

 

Looks good so far, let us know if there are any questions/issues.

 

 

Colin