neo4j-driver-core
Version:
Internals of neo4j-driver
75 lines (74 loc) • 2.71 kB
JavaScript
;
/**
* Copyright (c) "Neo4j"
* Neo4j Sweden AB [https://neo4j.com]
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
Object.defineProperty(exports, "__esModule", { value: true });
/**
* Cache which maps users to their last known home database, along with the last time the entry was accessed.
*
* @private
*/
var HomeDatabaseCache = /** @class */ (function () {
function HomeDatabaseCache(maxSize) {
this.maxSize = maxSize;
this.pruneCount = Math.max(Math.round(0.01 * maxSize * Math.log(maxSize)), 1);
this.map = new Map();
}
/**
* Updates or adds an entry to the cache, and prunes the cache if above the maximum allowed size
*
* @param {string} user cache key for the user to set
* @param {string} database new home database to set for the user
*/
HomeDatabaseCache.prototype.set = function (user, database) {
this.map.set(user, { database: database, lastUsed: Date.now() });
this._pruneCache();
};
/**
* retrieves the last known home database for a user
*
* @param {string} user cache key for the user to get
*/
HomeDatabaseCache.prototype.get = function (user) {
var value = this.map.get(user);
if (value !== undefined) {
value.lastUsed = Date.now();
return value.database;
}
return undefined;
};
/**
* removes the entry for a given user in the cache
*
* @param {string} user cache key for the user to remove
*/
HomeDatabaseCache.prototype.delete = function (user) {
this.map.delete(user);
};
/**
* Removes a number of the oldest entries in the cache if the number of entries has exceeded the maximum size.
*/
HomeDatabaseCache.prototype._pruneCache = function () {
if (this.map.size > this.maxSize) {
var sortedArray = Array.from(this.map.entries()).sort(function (a, b) { return a[1].lastUsed - b[1].lastUsed; });
for (var i = 0; i < this.pruneCount; i++) {
this.map.delete(sortedArray[i][0]);
}
}
};
return HomeDatabaseCache;
}());
exports.default = HomeDatabaseCache;