check-mirrors

#!/bin/bash

#region Constantes
URL_MIRRORLIST="https://www.archlinux.org/mirrorlist/?country=all&protocol=http&protocol=https&ip_version=4"
FILE="/tmp/mirrorlist.txt"
TEST_LIST="./test/testlist.txt"
PING_COUNT=5
ERASE="\e[K"
RE_MIRROR="(.*)\\s+(.*)"
#endregion

#region Colores
CLR_ROJO="\e[91m"
CLR_VERD="\e[92m"
CLR_AMAR="\e[93m"
CLR_FIN="\e[m"
#endregion

#region Funciones
_error() {
    if [ "$2" ]; then
        echo -e "${ERASE}${CLR_ROJO}check-mirrors: $2${CLR_FIN}" >&2
    fi
    exit $1
}

_success() {
    printf "${ERASE}%s: ${CLR_VERD}%s${CLR_FIN}\n" "$1" "$2"
}
#endregion

main() {
    obtener_lista || _error 1 "no se pudo obtener la lista de mirrors"
    procesar_lista
}

obtener_lista() {
    local cols=$(tput cols)
    local pad=31
    local size=$(($cols - $pad))
    echo -en "Obteniendo lista de mirrors ${CLR_AMAR}${URL_MIRRORLIST:0:$size}${CLR_FIN}...\r"

    wget "$URL_MIRRORLIST" -O "$FILE" > /dev/null 2>&1

    # FILE="$TEST_LIST"
}

procesar_lista() {
    local min_avg=400
    local min_url=
    local min_pais=

    IFS=$'\n'
    for linea in $(obtener_mirrors); do
        if [[ $linea =~ $RE_MIRROR ]]; then
            local pais="${BASH_REMATCH[1]}"
            local url="${BASH_REMATCH[2]}"

            printf "${ERASE}Pingeando ${CLR_AMAR}%s${CLR_FIN} (%s)...\r" "$url" "$pais"

            local avg_time=$(probar_mirror "$url")

            if [ $avg_time ]; then
                if es_menor $avg_time $min_avg; then
                    min_avg=$avg_time
                    min_url=$url
                    min_pais="$pais"
                fi
            fi
        else
            _error 2 "error de regex: [$linea]"
        fi
    done

    _success "Mejor mirror" "$min_url"
    _success "Pais" "$min_pais"
    _success "Tiempo" "$min_avg ms"
}

obtener_mirrors() {
    # Obtiene la lista de mirrors, almacenados en el archivo temporal.
    cat "$FILE" | awk -F '/' '
        $1 ~ /^##/ {
            gsub("## ", "")
            pais=$0
        }
        $1 ~ /Server/ {
            printf "%s\t%s\n", pais, $3
        }
    '
}

probar_mirror() {
    # Hace ping a la url y se obtiene el tiempo promedio.
    # $1: url
    ping -c $PING_COUNT "$1" |
        tail -1 |
        awk -F '/' '{ print $5 }'
}

es_menor() {
    [ $(echo "$1 < $2" | bc -l) -eq 1 ]
}

main "$@"