fast-geoip/build/index.js

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

"use strict";
var fs = require("fs");
var path = require("path");
var utils = require("./utils");
var params = require('./params');
var cacheEnabled = false;
var ipCache = {};
var locationCache;
var DATA_DIR = path.join(path.dirname(__dirname), "data");
function enableCache() {
    if (!cacheEnabled) {
        locationCache = readFile("locations.json").then(function (data) {
            cacheEnabled = true;
            return data;
        });
    }
}
function readFile(filename) {
    if (cacheEnabled && ipCache[filename] != undefined) {
        return Promise.resolve(ipCache[filename]);
    }
    return new Promise(function (resolve, reject) {
        fs.readFile(path.join(DATA_DIR, filename), function (err, data) {
            if (err) {
                reject(err);
            }
            else if (data == undefined) {
                reject();
            }
            else {
                var content = JSON.parse(data.toString());
                resolve(content);
                if (cacheEnabled) {
                    ipCache[filename] = content;
                }
            }
        });
    });
}
function readFileChunk(filename, offset, length) {
    return new Promise(function (resolve, reject) {
        fs.open(path.join(DATA_DIR, filename), 'r', function (err, fd) {
            if (err)
                reject(err);
            var buf = Buffer.alloc == undefined ? new Buffer(length) : Buffer.alloc(length);
            fs.read(fd, buf, 0, length, offset, function (err, _, buffer) {
                fs.close(fd, function () { });
                if (err)
                    reject(err);
                resolve(JSON.parse(buffer.toString()));
            });
        });
    });
}
function readLocationRecord(index) {
    if (cacheEnabled) {
        return locationCache.then(function (locations) {
            return locations[index];
        });
    }
    else {
        return readFileChunk("locations.json", index * params.LOCATION_RECORD_SIZE + 1, params.LOCATION_RECORD_SIZE - 1);
    }
}
function firstArrayItem(item) {
    return item[0];
}
function getNextIp(data, index, currentNextIp, extractKey) {
    if (index < (data.length - 1)) {
        return extractKey(data[index + 1]);
    }
    else {
        return currentNextIp;
    }
}
function lookup4(stringifiedIp) {
    var ip = utils.ipStr2Num(stringifiedIp);
    var rootIndex;
    var ipData;
    var nextIp = utils.ipStr2Num("255.255.255.255");
    return readFile("index.json")
        .then(function (data) {
        // IP cannot be NaN
        if (Object.is(ip, NaN))
            throw "IP cannot be NaN";
        rootIndex = utils.binarySearch(data, ip, utils.identity);
        if (rootIndex == -1) {
            // Ip is not in the database, return empty object
            throw "IP not found in the database";
        }
        nextIp = getNextIp(data, rootIndex, nextIp, utils.identity);
        return readFile("i" + rootIndex + ".json");
    })
        .then(function (data) {
        var index = utils.binarySearch(data, ip, utils.identity) + rootIndex * params.NUMBER_NODES_PER_MIDINDEX;
        nextIp = getNextIp(data, index, nextIp, utils.identity);
        return readFile(index + ".json");
    }).then(function (data) {
        var index = utils.binarySearch(data, ip, firstArrayItem);
        ipData = data[index];
        if (ipData[1] == null) {
            throw "IP doesn't any region nor country associated";
        }
        nextIp = getNextIp(data, index, nextIp, firstArrayItem);
        return readLocationRecord(ipData[1]);
    }).then(function (data) {
        return {
            range: [ipData[0], nextIp],
            country: data[0],
            region: data[1],
            eu: data[5],
            timezone: data[4],
            city: data[2],
            ll: [ipData[2], ipData[3]],
            metro: data[3],
            area: ipData[4]
        };
    }).catch(function () {
        return null;
    });
}
module.exports = {
    lookup: lookup4,
    enableCache: enableCache
};