Update v2ray config IPs to preferred Cloudflare CDN addresses

update_v2ray_ip.sh

#!/usr/bin/env bash
# vim: set ts=4 sw=4 sts=4 et:

set -euo pipefail

V2RAY_CFG=/usr/local/etc/v2ray/config.json
CFST_DIR=.
DRY_RUN=false

panic() {
    echo "Error: $*" >&2
    exit 1
}

usage() {
    cat <<EOF
Usage: $0 [OPTIONS] [v2ray_cfg]
Options:
  --cfst-dir <DIR>   Directory containing cfst binary (default: .)
  -h, --help         Show this help message

  v2ray_cfg          Print commands only, do not modify config or restart v2ray
EOF
    exit 1
}

parse_args() {
    local parsed

    # shellcheck disable=SC2155
    parsed=$(getopt -o h -l cfst-dir:,help -n "$0" -- "$@")
    eval set -- "$parsed"

    while true; do
        case "$1" in
        --cfst-dir)
            CFST_DIR=$2
            shift 2
            ;;
        -h|--help)
            usage
            ;;
        --)
            shift
            break
            ;;
        *)
            panic "Internal error"
            ;;
        esac
    done

    [[ -n "${1:-}" ]] || return 0
    V2RAY_CFG=$1
    DRY_RUN=true
}

get_origin_ips() {
    jq -r '.outbounds[].settings.vnext[0]?.address // empty' "$V2RAY_CFG"
}

get_current_ips() {
    local count=$1

    (cd "$CFST_DIR" && ./cfst -p "$count" -o "") 2>/dev/null | sed -n '/^IP/,$ {
/^IP/d
s/\s\+.*//p
}'
}

intersect() {
    local -n arr1=$1
    local -n arr2=$2
    local -n result=$3

    for ip1 in "${arr1[@]}"; do
        for ip2 in "${arr2[@]}"; do
            [[ "$ip1" == "$ip2" ]] || continue
            # shellcheck disable=SC2034
            result["$ip1"]=1
            break
        done
    done
}

build_modify_map() {
    local -n origin_arr=$1
    local -n current_arr=$2
    local -n map=$3

    local -A same
    intersect origin_arr current_arr same

    local i=0
    for src in "${origin_arr[@]}"; do
        [[ -z "${same[$src]:-}" ]] || continue

        while [[ $i -lt ${#current_arr[@]} ]]; do
            local target="${current_arr[$i]}"
            ((++i))

            [[ -z "${same[$target]:-}" ]] || continue

            # shellcheck disable=SC2034
            map["$src"]=$target
            break
        done
    done
}

generate_sed_cmd() {
    local -n modify_arr=$1

    for src in "${!modify_arr[@]}"; do
        echo "-e s/\"$src\"/\"${modify_arr[$src]}\"/"
    done
}

update_v2ray_cfg() {
    local cmd=$1
    local opt=""
    $DRY_RUN || opt=-i

    # shellcheck disable=SC2086
    sed $opt $cmd "$V2RAY_CFG"
}

restart_v2ray() {
    $DRY_RUN || systemctl restart v2ray
}

main() {
    parse_args "$@"

    command -v jq &>/dev/null || \
        panic "Not found jq! Please apt install jq"

    [[ -x "$CFST_DIR/cfst" ]] || \
        panic "cfst is not executable! Please download from https://github.com/XIU2/CloudflareSpeedTest"

    local -a origin
    mapfile -t origin < <(get_origin_ips)
    [[ ${#origin[@]} -gt 0 ]] || panic "Failed to get origin IPs from config"

    local -a current
    mapfile -t current < <(get_current_ips "${#origin[@]}")
    [[ ${#current[@]} -eq ${#origin[@]} ]] || \
        panic "IP count mismatch: origin=${#origin[@]}, current=${#current[@]}"

    local -A modify
    build_modify_map origin current modify

    [[ ${#modify[@]} -gt 0 ]] || return 0

    echo -n 'Modify v2ray config: '
    for src in "${!modify[@]}"; do
        echo -n "$src -> ${modify[$src]} "
    done
    echo

    update_v2ray_cfg "$(generate_sed_cmd modify)"
    restart_v2ray
}

main "$@"