What is the best way to override an existing shell command? - bash

Question

If one were to have a need to do modify an existing shell command (built-in or otherwise), what is the best way to go about this?
Let me state that I understand there are a number of potential risks involved in attempting a procedure such as this, but that is the very reason I ask this question.
I would like to create a shell function (called ping) to use in place of the common ping command. For the sake of this topic, let's say that it should at the very least be compatible in both Bash and Zsh shell environments.
Specifically, I would like to allow for ping to accept full URLs in the hostname (with protocol, trailing slash/pathname, query parameters, etc). The string manipulation is not what is stumping me, but rather how to properly execute the original ping executable without calling the function something other than ping.
For example, the following two commands should yield the same result:
# EXAMPLE 2 (What `ping` will accept)
ping who.is
# EXAMPLE 1 (What I would like to be able to do with `ping`)
ping https://who.is/my/ping/?example=this

Answer 1

A shim might look like the following (if your real ping is in /usr/bin):
#!/usr/bin/env bash
uri_re='^[[:alnum:]]+://([^/]+)/'
if [[ $1 =~ $uri_re ]]; then
exec /usr/bin/ping "${BASH_REMATCH[1]}" "${#:2}"
else
exec /usr/bin/ping "$#"
fi
Put it somewhere like /opt/overrides/bin, and put that earlier in the PATH than /usr/bin (so PATH=/opt/overrides/bin:/bin:/usr/bin:/usr/local/bin or such).
Or, for a portable function that will work on all POSIX-compliant shells (and zsh as well, even though it doesn't try to be one):
ping() {
local _ping_addr >/dev/null 2>&1 ||: "ignore failure on shells that don't support local"
case $1 in
*://*/)
_ping_addr=${1#*://}
_ping_addr=${_ping_addr%%/*}
shift
command ping "$_ping_addr" "$#"
;;
*)
command ping "$#" ;;
esac
}

Answer 2

I'd like to address #blizzrdof77's original question (paraphrased below):
"I would like to create a shell function (called 'ping') to use in place of the common ping🛈 command." [ℹ]
This drop-in portable shell function [ℹ] works well on Mac & Linux in zsh,bash,sh, and all POSIX-compliant shells.
# ---------------------------------------------------------
# Better `ping` support for various URL formats/protocols
#
# #param $1 - hostname
# EXAMPLE USAGE: `ping http://google.com/`
# ---------------------------------------------------------
ping() {
local pingdomain="$1"
shopt -s nocasematch # allow lowercase
pingdomain=${pingdomain/#*:\/\/} # strip protocol
pingdomain=${pingdomain/#*:*#/} # strip leading 'user:pass#'
pingdomain=$(echo "${pingdomain//"?"//}") # remove '?'
pingdomain="$(echo "$pingdomain" | cut -d/ -f 1)" # clear last '/'
command ping $pingdomain
}