*Redirect http to https and remove www from URL*

Just use "https://" in your redirect.

HTTP::redirect "https://..."

can same iRule be used to modify any http site (not specific) such as http://xyz.com to https://xyz.com.

e.g.

[root@ve11a:Active:Changes Pending] config  tmsh list ltm virtual bar
ltm virtual bar {
    destination 172.28.20.111:80
    ip-protocol tcp
    mask 255.255.255.255
    profiles {
        http { }
        tcp { }
    }
    rules {
        myrule
    }
    source 0.0.0.0/0
    source-address-translation {
        type automap
    }
    vs-index 28
}
[root@ve11a:Active:Changes Pending] config  tmsh list ltm rule myrule
ltm rule myrule {
    when HTTP_REQUEST {
  HTTP::redirect "https://[string map {"www." ""} [HTTP::host]][HTTP::uri]"
}
}

[root@ve11a:Active:Changes Pending] config  curl -I http://172.28.20.111/something -H "Host: www.xyz.com"
HTTP/1.0 302 Found
Location: https://xyz.com/something
Server: BigIP
Connection: Keep-Alive
Content-Length: 0

[root@ve11a:Active:Changes Pending] config  curl -I http://172.28.20.111/something -H "Host: xyz.com"
HTTP/1.0 302 Found
Location: https://xyz.com/something
Server: BigIP
Connection: Keep-Alive
Content-Length: 0

thanks so much for the answers.. i will try both.

That's one way to do it. You can also use Nitass' [string map ] recommendation, or even some [findstr ] syntax:

when HTTP_REQUEST {
    if { [string tolower [HTTP::host]] starts_with "www." } {
        HTTP::redirect "https://[findstr [string tolower [HTTP::host]] "www." 4][HTTP::uri]" 
    }
}

Kevin: Thank you so much.. This worked great. when HTTP_REQUEST { if { [string tolower [HTTP::host]] starts_with "www." } { HTTP::redirect "https://[findstr [string tolower [HTTP::host]] "www." 4][HTTP::uri]" } }