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Log4j2's avatar
Log4j2
Icon for Altocumulus rankAltocumulus
May 10, 2022
Solved

iRule [string range...] not chunking data properly

I have an irule (much of which I found here) that is to gather some much needed troubleshooting data I need in regards to the headers and payload I have coming in.  The payload is obvisouly too large...
chunk
event
irule
payload
splitting
tcl
  • PeteWhite's avatar
    PeteWhite
    May 11, 2022

    In fact I have just grabbed this from an iRule i recently wrote. Almost the same, with fixed values. Note the end is 99 but the increment is 100. As you say, string range is zero-indexed

    for {set start 0; set end 99} {$start < [HTTP::payload length]} {incr start 100;incr end 100} {
            log local0.debug "[string range [HTTP::payload] $start $end ]"
        }
PeteWhite's avatar
PeteWhite
Icon for Employee rankEmployee
May 11, 2022

How about somehting like this:

for { set start 0; set end $static::max_chars} { $start < [HTTP::payload length] } { incr start $static::max_chars; incr end $static::max_chars } {
	log local0.debug "$start:$end [string range [HTTP::payload] $start $end]"
}
PeteWhite's avatar
PeteWhite
Icon for Employee rankEmployee
May 11, 2022

In fact I have just grabbed this from an iRule i recently wrote. Almost the same, with fixed values. Note the end is 99 but the increment is 100. As you say, string range is zero-indexed

for {set start 0; set end 99} {$start < [HTTP::payload length]} {incr start 100;incr end 100} {
            log local0.debug "[string range [HTTP::payload] $start $end ]"
        }