@omgovich/firebase-functions-rate-limiter
Version:
JS/TS library that allows you to set per - time, per - user or per - anything limits for calling Firebase cloud functions
143 lines • 7.75 kB
JavaScript
"use strict";
var __assign = (this && this.__assign) || function () {
__assign = Object.assign || function(t) {
for (var s, i = 1, n = arguments.length; i < n; i++) {
s = arguments[i];
for (var p in s) if (Object.prototype.hasOwnProperty.call(s, p))
t[p] = s[p];
}
return t;
};
return __assign.apply(this, arguments);
};
var __awaiter = (this && this.__awaiter) || function (thisArg, _arguments, P, generator) {
function adopt(value) { return value instanceof P ? value : new P(function (resolve) { resolve(value); }); }
return new (P || (P = Promise))(function (resolve, reject) {
function fulfilled(value) { try { step(generator.next(value)); } catch (e) { reject(e); } }
function rejected(value) { try { step(generator["throw"](value)); } catch (e) { reject(e); } }
function step(result) { result.done ? resolve(result.value) : adopt(result.value).then(fulfilled, rejected); }
step((generator = generator.apply(thisArg, _arguments || [])).next());
});
};
var __generator = (this && this.__generator) || function (thisArg, body) {
var _ = { label: 0, sent: function() { if (t[0] & 1) throw t[1]; return t[1]; }, trys: [], ops: [] }, f, y, t, g;
return g = { next: verb(0), "throw": verb(1), "return": verb(2) }, typeof Symbol === "function" && (g[Symbol.iterator] = function() { return this; }), g;
function verb(n) { return function (v) { return step([n, v]); }; }
function step(op) {
if (f) throw new TypeError("Generator is already executing.");
while (_) try {
if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
if (y = 0, t) op = [op[0] & 2, t.value];
switch (op[0]) {
case 0: case 1: t = op; break;
case 4: _.label++; return { value: op[1], done: false };
case 5: _.label++; y = op[1]; op = [0]; continue;
case 7: op = _.ops.pop(); _.trys.pop(); continue;
default:
if (!(t = _.trys, t = t.length > 0 && t[t.length - 1]) && (op[0] === 6 || op[0] === 2)) { _ = 0; continue; }
if (op[0] === 3 && (!t || (op[1] > t[0] && op[1] < t[3]))) { _.label = op[1]; break; }
if (op[0] === 6 && _.label < t[1]) { _.label = t[1]; t = op; break; }
if (t && _.label < t[2]) { _.label = t[2]; _.ops.push(op); break; }
if (t[2]) _.ops.pop();
_.trys.pop(); continue;
}
op = body.call(thisArg, _);
} catch (e) { op = [6, e]; y = 0; } finally { f = t = 0; }
if (op[0] & 5) throw op[1]; return { value: op[0] ? op[1] : void 0, done: true };
}
};
Object.defineProperty(exports, "__esModule", { value: true });
exports.GenericRateLimiter = void 0;
var ow_1 = require("ow");
var FirebaseFunctionsRateLimiterConfiguration_1 = require("./FirebaseFunctionsRateLimiterConfiguration");
var GenericRateLimiter = /** @class */ (function () {
function GenericRateLimiter(configuration, persistenceProvider, timestampProvider, debugFn) {
if (debugFn === void 0) { debugFn = function (msg) {
/* */
}; }
this.configuration = __assign(__assign({}, FirebaseFunctionsRateLimiterConfiguration_1.FirebaseFunctionsRateLimiterConfiguration.DEFAULT_CONFIGURATION), configuration);
(0, ow_1.default)(this.configuration, "configuration", ow_1.default.object);
FirebaseFunctionsRateLimiterConfiguration_1.FirebaseFunctionsRateLimiterConfiguration.ConfigurationFull.validate(this.configuration);
this.persistenceProvider = persistenceProvider;
(0, ow_1.default)(this.persistenceProvider, "persistenceProvider", ow_1.default.object);
this.timestampProvider = timestampProvider;
(0, ow_1.default)(this.timestampProvider, "timestampProvider", ow_1.default.object);
this.debugFn = debugFn;
}
GenericRateLimiter.prototype.isQuotaExceededOrRecordCall = function (qualifier) {
return __awaiter(this, void 0, void 0, function () {
var resultHolder;
var _this = this;
return __generator(this, function (_a) {
switch (_a.label) {
case 0:
resultHolder = {
isQuotaExceeded: false,
};
return [4 /*yield*/, this.persistenceProvider.updateAndGet(this.configuration.name, qualifier, function (record) {
return _this.runTransactionForAnswer(record, resultHolder);
})];
case 1:
_a.sent();
return [2 /*return*/, resultHolder.isQuotaExceeded];
}
});
});
};
GenericRateLimiter.prototype.isQuotaAlreadyExceededDoNotRecordCall = function (qualifier) {
return __awaiter(this, void 0, void 0, function () {
var timestampsSeconds, record, recentUsages;
return __generator(this, function (_a) {
switch (_a.label) {
case 0:
timestampsSeconds = this.getTimestampsSeconds();
return [4 /*yield*/, this.persistenceProvider.get(this.configuration.name, qualifier)];
case 1:
record = _a.sent();
recentUsages = this.selectRecentUsages(record.u, timestampsSeconds.threshold);
return [2 /*return*/, this.isQuotaExceeded(recentUsages.length)];
}
});
});
};
GenericRateLimiter.prototype.runTransactionForAnswer = function (input, resultHolder) {
var timestampsSeconds = this.getTimestampsSeconds();
this.debugFn("Got record with usages " + input.u.length);
var recentUsages = this.selectRecentUsages(input.u, timestampsSeconds.threshold);
this.debugFn("Of these usages there are" + recentUsages.length + " usages that count into period");
var result = this.isQuotaExceeded(recentUsages.length);
resultHolder.isQuotaExceeded = result;
this.debugFn("The result is quotaExceeded=" + result);
if (!result) {
this.debugFn("Quota was not exceeded, so recording a usage at " + timestampsSeconds.current);
recentUsages.push(timestampsSeconds.current);
}
var newRecord = {
u: recentUsages,
};
return newRecord;
};
GenericRateLimiter.prototype.selectRecentUsages = function (allUsages, timestampThresholdSeconds) {
var recentUsages = [];
for (var _i = 0, allUsages_1 = allUsages; _i < allUsages_1.length; _i++) {
var usageTime = allUsages_1[_i];
if (usageTime > timestampThresholdSeconds) {
recentUsages.push(usageTime);
}
}
return recentUsages;
};
GenericRateLimiter.prototype.isQuotaExceeded = function (numOfRecentUsages) {
return numOfRecentUsages >= this.configuration.maxCalls;
};
GenericRateLimiter.prototype.getTimestampsSeconds = function () {
var currentServerTimestampSeconds = this.timestampProvider.getTimestampSeconds();
return {
current: currentServerTimestampSeconds,
threshold: currentServerTimestampSeconds - this.configuration.periodSeconds,
};
};
return GenericRateLimiter;
}());
exports.GenericRateLimiter = GenericRateLimiter;
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