redis-rank
Version:
Manage real-time leaderboards using Redis
139 lines (138 loc) • 5.4 kB
JavaScript
;
Object.defineProperty(exports, "__esModule", { value: true });
exports.PeriodicLeaderboard = void 0;
var Leaderboard_1 = require("./Leaderboard");
/**
* Used by `getWeekNumber`. Needed because Date.getTime returns the time in UTC
* and we use local time.
*/
var msTimezoneOffset = new Date().getTimezoneOffset() * 60 * 1000;
/**
* Get the week number since January 1st, 1970
*
* 345600000 = 4 days in milliseconds
* 604800000 = 1 week in milliseconds
*
* Note: we add 4 days because January 1st, 1970 was thursday (and weeks start
* on sunday). I think it should be 3 days and not 4, but 3 result in
* incorrect values. ¯\_(ツ)_/¯
*/
var getWeekNumber = function (time) { return Math.floor((time.getTime() + 345600000 - msTimezoneOffset) / 604800000); };
/**
* Pad a number with leading zeroes
*
* @param input the number
* @param digits number of digits
*/
var padNumber = function (input, digits) {
if (digits === void 0) { digits = 2; }
return (input + '').padStart(digits, '0');
};
/**
* Note: default functions use local time to determine keys.
* Tip: You can specify the `now()` function in the periodic leaderboard options
* to offset the time however you like.
*
* Examples:
* * `yearly`: `y2020`
* * `weekly`: `w2650` (week number since epoch)
* * `monthly`: `y2020-m05`
* * `daily`: `y2020-m05-d15`
* * `hourly`: `y2020-m05-d15-h22`
* * `minute`: `y2020-m05-d15-h22-m53`
*/
var CYCLE_FUNCTIONS = {
'yearly': function (time) { return "y".concat(time.getFullYear()); },
'weekly': function (time) { return "w".concat(padNumber(getWeekNumber(time), 4)); },
'monthly': function (time) { return "".concat(CYCLE_FUNCTIONS['yearly'](time), "-m").concat(padNumber(time.getMonth())); },
'daily': function (time) { return "".concat(CYCLE_FUNCTIONS['monthly'](time), "-d").concat(padNumber(time.getDate())); },
'hourly': function (time) { return "".concat(CYCLE_FUNCTIONS['daily'](time), "-h").concat(padNumber(time.getHours())); },
'minute': function (time) { return "".concat(CYCLE_FUNCTIONS['hourly'](time), "-m").concat(padNumber(time.getMinutes())); }
};
var PeriodicLeaderboard = /** @class */ (function () {
/**
* Create a new periodic leaderboard
*
* Use `getCurrentLeaderboard` to get the leaderboard of the current cycle
*
* @param client ioredis client
* @param baseKey prefix for all the leaderboards
* @param options periodic leaderboard options
*/
function PeriodicLeaderboard(client, baseKey, options) {
this.client = client;
this.baseKey = baseKey;
this.options = options;
this.leaderboards = new Map();
}
/**
* Get the cycle key at a specified date and time
*
* @param time the time
*/
PeriodicLeaderboard.prototype.getKey = function (time) {
return (CYCLE_FUNCTIONS[this.options.cycle] || this.options.cycle)(time);
};
/**
* Get the leaderboard for the provided cycle key
*
* @param key cycle key
*/
PeriodicLeaderboard.prototype.getLeaderboard = function (key) {
var finalKey = "".concat(this.baseKey, ":").concat(key);
var lb = this.leaderboards.get(finalKey);
if (lb)
return lb; // hit cache
// Note: avoid leaking leaderboards
if (this.leaderboards.size > 100)
this.leaderboards.clear();
lb = new Leaderboard_1.Leaderboard(this.client, finalKey, this.options.leaderboardOptions);
this.leaderboards.set(finalKey, lb);
return lb;
};
/**
* Get the leaderboard at the specified date and time. If `time` is not
* provided, it will use the time returned by `now()`.
*
* @param time the time
*/
PeriodicLeaderboard.prototype.getLeaderboardAt = function (time) {
return this.getLeaderboard(time ? this.getKey(time) : this.getKeyNow());
};
/**
* Get the cycle key that should be used based on the time returned
* by `now()`
*/
PeriodicLeaderboard.prototype.getKeyNow = function () {
return this.getKey(this.options.now ? this.options.now() : new Date());
};
/**
* Get the current leaderboard based on the time returned by `now()`
*/
PeriodicLeaderboard.prototype.getLeaderboardNow = function () {
return this.getLeaderboard(this.getKeyNow());
};
/**
* Find all the active cycle keys in the database.
* Use this function sparsely, it uses `SCAN` over the whole database to
* find matches.
*
* Complexity: `O(N)` where N is the number of keys in the Redis database
*/
PeriodicLeaderboard.prototype.getExistingKeys = function () {
var _this = this;
return new Promise(function (resolve, reject) {
var stream = _this.client.scanStream({
match: "".concat(_this.baseKey, ":*"),
count: 100
});
var keys = new Set();
var addKey = keys.add.bind(keys);
stream.on('data', function (batch) { return batch.map(addKey); });
stream.on('error', reject);
stream.on('end', function () { return resolve(Array.from(keys).map(function (key) { return key.slice(_this.baseKey.length + 1); })); });
});
};
return PeriodicLeaderboard;
}());
exports.PeriodicLeaderboard = PeriodicLeaderboard;