Bash script to append aliases to peer IDs in Wireguard output

wg_aliases.sh

#!/bin/bash

# To the extent possible under law, I hereby waive all copyright
# and related or neighboring rights to this program.

# Determine the path of this script, to read the aliases file relative to that
parent_path=$( cd "$(dirname "${BASH_SOURCE[0]}")" ; pwd -P )

# Check if the unbuffer command is available.
# It is used to retain colored output from wg show
if [ -x "$(command -v unbuffer)" ]; then
  has_unbuffer=true
else
  has_unbuffer=false
fi


# Read the wg_aliases.txt file and store the contents in an associative array
declare -A aliases
while read -r line; do
  peer_id=$(echo "$line" | awk '{print $1}')
  alias=$(echo "$line" | cut -d' ' -f2-)
  aliases["$peer_id"]="$alias"
done < "$parent_path/wg_aliases.txt"

# Get the WireGuard connection status
if [ "$has_unbuffer" = true ] ; then
  wg_output=$(unbuffer wg show)
else
  wg_output=$(wg show)
fi

# Iterate over each line of the wg output
while IFS= read -r line; do
  # Check if line contains "peer"
  if [[ $line == *peer* ]]; then
    # Extract the peer ID
    peer_id=$(echo "$line" | sed -e 's@\x1b\[[0-9;]*m@@g' | awk '{print $2}')

    # Check if the line is not empty
    if [[ -n $peer_id ]]; then
      # Check if the peer ID has an alias
      if [[ -n ${aliases["$peer_id"]} ]]; then
        # Get the alias for the peer ID
        alias="${aliases["$peer_id"]}"

        # Modify the line to include the alias in parenthesis
        modified_line=$(echo "$line" | sed "s@$peer_id@$peer_id ($alias)@")

        # Print the modified line
        echo -e "$modified_line"
      else
        # Print the line as is if no alias is found
        echo "$line"
      fi
    else
      echo "$line"
    fi
  else
    echo "$line"
  fi
done <<< "$wg_output"

wg_aliases.txt

uLqAm7B9StcjwwtL9ZWPteh2kFbtkpZziQwab8joU5i= Node 1
oVo972LTd6ASJN4AFqn7jSp9uYEgc47FxJtw5FDxj2E= Node 2