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Pirlo's avatar
Pirlo
Icon for Nimbostratus rankNimbostratus
Dec 30, 2014

URI inspect - Rewrite - Redirect

DevGods

 

I am trying to inspect URI and Insert into a newly formatted redirect. I am trying to use the URI Interrogation code to dump the params then formulate the redirect.

 

If I read the code correctly I should be able to dump the query into param format then I FEASIBLY should be able to write a rule that would look something like this correct?

 

when HTTP_REQUEST {

 

set namevals [split [HTTP::query] "&"]

 

for {set i 0} {$i < [llength $namevals]} {incr i} {

 

set params [split [lindex $namevals $i] "="]

 

set pnum [expr $i+1]

 

log local0. "Param[$pnum]: [lindex $params 0]"

 

log local0. "Value[$pnum]: [URI::query [HTTP::uri] [lindex $params 0]]"

 

if { [HTTP::uri] starts_with "/receiptLocator" } {

 

HTTP::redirect "https://my.domain.com/ReceiptLocator=$pnum1&CityOrigin=$pnum2&FirstName=$pnum3&LastName=$pnum4"

 

URI Interrogation

 

Incoming URI I will inspect

 

receiptLocator=ABCDEF&originCity=BOS&firstName=John&lastName=Doe&language=en

 

Rewritten and Redirected URI

 

ReceiptLocator=ABCDEF&CityOrigin=BOS&FirstName=John&LastName=Doe

 

application delivery
devops
iRules

4 Replies

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  • StephanManthey's avatar
    StephanManthey
    Icon for MVP rankMVP
    Dec 30, 2014

    Your sample code loops through all query parameters and would send a redirect per parameter (as there is no closing curly bracket before doing the redirect).

     

    To make the code more rubust I would not count on the expected order of parameters. A jump table (switch) may help to assign the proper value to each parameter.

     

  • StephanManthey's avatar
    StephanManthey
    Icon for MVP rankMVP
    Dec 30, 2014

    You can try the following code, please:

     

    when HTTP_REQUEST {

    if {[HTTP::query] ne "" && !([HTTP::query] starts_with "ReceiptLocator") } {
        set namevals [split [HTTP::query] "&"]
        log local0. "[HTTP::query]; number of params: <[llength ${namevals}]>"

        for {set i 0} {$i < [llength ${namevals}]} {incr i} {
            set param [split [lindex ${namevals} $i] "="]
            log local0. "current parameter: <$param>, <${i}> of <[llength ${namevals}]>"
            log local0. "param_name: <[lindex $param 0]>, param_value <[lindex $param 1]>"
            switch [string tolower [lindex $param 0]] {
                "receiptlocator" { set ReceiptLocator [lindex $param 1] }
                "origincity" { set CityOrigin [lindex $param 1] }
                "firstname" { set FirstName [lindex $param 1]}
                "lastname" {set LastName [lindex $param 1]}
            }
        }
        if { [info exists ReceiptLocator] && [info exists CityOrigin] && [info exists FirstName] && [info exists LastName] } {
            HTTP::redirect "HTTP::redirect https://[getfield [HTTP::host] ":" 1][HTTP::path]?ReceiptLocator=${ReceiptLocator}&CityOrigin=${CityOrigin}&FirstName=${FirstName}&LastName={LastName}"
        } else {
            log local0. "missing parameters"
        }
    } else {
        log local0. "no query data or query already in expected format"
    }
}
  • nitass's avatar
    nitass
    Icon for Employee rankEmployee
    Dec 31, 2014

    this is just another example.

     configuration

[root@ve11a:Active:In Sync] config  tmsh list ltm virtual bar
ltm virtual bar {
    destination 172.28.24.10:80
    ip-protocol tcp
    mask 255.255.255.255
    pool foo
    profiles {
        http { }
        tcp { }
    }
    rules {
        qux
    }
    source 0.0.0.0/0
    source-address-translation {
        type automap
    }
    vs-index 2
}
[root@ve11a:Active:In Sync] config  tmsh list ltm rule qux
ltm rule qux {
    when RULE_INIT {
  set static::param {receiptLocator originCity firstName lastName}
  set static::newparam {ReceiptLocator CityOrigin FirstName LastName}
  set static::len [llength $static::param]
}
when HTTP_REQUEST {
  if { [HTTP::uri] starts_with "/receiptLocator" } {
    set newuri "/"
    for {set i 0} {$i < $static::len} {incr i} {
      set pvalue [URI::query "?[string trimleft [HTTP::uri] /]" [lindex $static::param $i]]
      if { $newuri ne "/" } {
        append newuri "&"
      }
      append newuri "[lindex $static::newparam $i]=$pvalue"
    }
    HTTP::redirect "http://[HTTP::host]$newuri"
  } else {
     do nothing
  }
}
}

 test

[root@ve11a:Active:In Sync] config  curl -i "http://172.28.24.10/receiptLocator=ABCDEF&originCity=BOS&firstName=John&lastName=Doe&language=en"
HTTP/1.0 302 Found
Location: http://172.28.24.10/ReceiptLocator=ABCDEF&CityOrigin=BOS&FirstName=John&LastName=Doe
Server: BigIP
Connection: Keep-Alive
Content-Length: 0
  • StephanManthey's avatar
    StephanManthey
    Icon for MVP rankMVP
    Dec 31, 2014

    I noticed a mistake in my first sample (missing variable declaration in response definition).

     

    (For whatever reason I cannot change the previous post.)

     

    Here is the corrected code including a switch for turning debugging on/off and allowing both ampersand and semicolon for parameter separation in query:

     

    when HTTP_REQUEST {

     enable (1), disable (0) debugging
    set debug 0
    if {[HTTP::query] ne "" && !([HTTP::query] starts_with "ReceiptLocator") } {

         split query into parameters separated by semicolon or ampersand
        set namevals [split [HTTP::query] ";&"]
        if { $debug > 0 } {
            log local0. "original query: <[HTTP::query]>; number of params: <[llength ${namevals}]>"
        }

         loop through all parameters
        for {set i 0} {$i < [llength ${namevals}]} {incr i} {

             read parameter name and value
            set param [split [lindex ${namevals} $i] "="]
            if { $debug > 0 } {
                log local0. "current parameter: <$param>, <[expr {${i} + 1}]> of <[llength ${namevals}]>"
                log local0. "param_name: <[lindex $param 0]>, param_value <[lindex $param 1]>"
            }

             assign variable values for redirect
            switch [string tolower [lindex $param 0]] {
                "receiptlocator" { set ReceiptLocator [lindex $param 1] }
                "origincity" { set CityOrigin [lindex $param 1] }
                "firstname" { set FirstName [lindex $param 1]}
                "lastname" {set LastName [lindex $param 1]}
            }
        }

         redirect only if variables are set
        if { [info exists ReceiptLocator] && [info exists CityOrigin] && [info exists FirstName] && [info exists LastName] } {
            HTTP::redirect "HTTP::redirect https://[getfield [HTTP::host] ":" 1][HTTP::path]?ReceiptLocator=${ReceiptLocator}&CityOrigin=${CityOrigin}&FirstName=${FirstName}&LastName=${LastName}"
        } else {
            if { $debug > 0 } {
                log local0. "missing parameters in query"
            }
        }
    } else {
        if { $debug > 0 } {
            log local0. "no query data or query already in expected format"
        }
    }
}

    For testing locally on the F5 device I´m using the same approach as Nitass:

     

     curl -i http://10.131.131.120/test?receiptLocator=ABCDEF\;originCity=BOS\;firstName=John\&lastName=Doe\;language=en
HTTP/1.0 302 Found
Location: HTTP::redirect https://10.131.131.120/test?ReceiptLocator=ABCDEF&CityOrigin=BOS&FirstName=John&LastName=Doe
Server: BigIP
Connection: Keep-Alive
Content-Length: 0