fast-geoip/build/utils.js

A faster & low-memory replacement for geoip-lite, a node library that maps IPs to geographical information

"use strict";
function identity(item) {
    return item;
}
function binarySearch(list, item, extractKey) {
    var low = 0;
    var high = list.length - 1;
    while (true) {
        var i = Math.round((high - low) / 2) + low;
        if (item < extractKey(list[i])) {
            if (i == high && i == low) {
                return -1; // Item is lower than the first item
            }
            else if (i == high) {
                high = low;
            }
            else {
                high = i;
            }
        }
        else if (item >= extractKey(list[i]) && (i == (list.length - 1) || item < extractKey(list[i + 1]))) {
            return i;
        }
        else {
            low = i;
        }
    }
}
function ipStr2Num(stringifiedIp) {
    return stringifiedIp.split('.')
        .map(function (e) {
        return parseInt(e);
    })
        .reduce(function (acc, val, index) {
        return acc + val * Math.pow(256, 3 - index);
    }, 0);
}
module.exports = {
    binarySearch: binarySearch,
    identity: identity,
    ipStr2Num: ipStr2Num
};