How to change a put into a post

You will have to do something like this similar to this post, https://devcentral.f5.com/questions/irule-to-change-http-get-into-post:

when CLIENT_ACCEPTED {
    TCP::collect
}
when CLIENT_DATA {
     separate uri and query string
    set uri [findstr [TCP::payload] "PUT " 4 " HTTP/1."]
    switch -glob $uri {
        "/data/rest/abc/list/shared/*" -
        "/data/rest/abc/list/tag/*" -
        "/data/rest/abc/group/*" {
            set uri_no_query [findstr $uri "" 0 "?"]
            set query [findstr $uri "?" 1]

             replace TCP payload
            regsub -all -nocase "PUT" [TCP::payload] "POST" newdata
            set newdata1 [string map "$uri $uri_no_query" $newdata]
            regsub -all -nocase "Accept: " $newdata1 "Content-Type: application/x-www-form-urlencoded\r\nContent-Length: [string length $query]\r\nAccept: " newdata2
            TCP::payload replace 0 [TCP::payload length] ${newdata2}$query
        }
    }
    TCP::release
}