Forum Discussion

Anthony_Porcano's avatar
Anthony_Porcano
Icon for Nimbostratus rankNimbostratus
Apr 15, 2007

matches_regex and matchclass

Is there any way to apply a regular expression to matchclass? Apologies in advance if I'm missing something obvious here, but my attempts thus far are not working.

 

 

if { [ matchclass [HTTP::path] matches_reqex "\/portal\/($::flaggedpaths)\?" ] } {

 

log local0. "matched [HTTP::path] in flaggedpaths class"

 

}

 

 

Returns:

 

[invalid option "matches_reqex" must be: contains ends_with equals starts_with] [matches_reqex]

 

 

The error seems clear enough. You can only use a subset of the available relational operators with the matchclass command. Am I interpretting this correctly? Is there another way to accomplish pattern matching against a class?

 

 

Thanks in advance,

 

Anthony
application delivery
dev
devops
iRules

1 Reply

  • Joe_Pruitt's avatar
    Joe_Pruitt
    Apr 16, 2007
    Unfortunately, as you've found out, matchclass is limited to only the operators listed in that error. But, you aren't completely stuck. While it's not as elegant as a single matchclass line, classes are interpreted as TCL lists, so you can use the TCL list commands to loop through the elements and do whatever you want.

    This should be equivalent (or close to it).

    when HTTP_REQUEST {
  foreach path $::flaggedpaths {
    if { [HTTP::path] starts_with "/portal/$path" } {
      log local0. "matched [HTTP::path] in flaggedpaths class member '$path'"
      break
    }
  }
}

    You could have used a matches_regexp but I went with the string comparison approach as that avoids the overhead associated with the regular expression comparison.

    And, yes, it goes both ways with matchclass. You can also pass in a user created TCL lists instead of a class if you so desire...

    -Joe