@lightbend/akkaserverless-javascript-sdk
Version:
Akka Serverless JavaScript SDK
220 lines (204 loc) • 7.04 kB
JavaScript
/*
* Copyright 2021 Lightbend Inc.
*
* 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.
*/
const debug = require('debug')('akkaserverless-replicated-entity');
const ReplicatedRegister = require('./register');
const AnySupport = require('../protobuf-any');
const protobufHelper = require('../protobuf-helper');
const iterators = require('./iterators');
const util = require('util');
const Clocks =
protobufHelper.moduleRoot.akkaserverless.component.replicatedentity
.ReplicatedEntityClock;
/**
* @classdesc A replicated map of registers.
*
* @constructor module:akkaserverless.replicatedentity.ReplicatedRegisterMap
* @implements module:akkaserverless.replicatedentity.ReplicatedData
*/
function ReplicatedRegisterMap() {
const registers = new Map();
const removed = new Map();
let cleared = false;
/**
* Get the value at the given key.
*
* @function module:akkaserverless.replicatedentity.ReplicatedRegisterMap#get
* @param {module:akkaserverless.Serializable} key The key to get.
* @returns {number|undefined} The register value, or undefined if no value is defined at that key.
*/
this.get = (key) => {
const entry = registers.get(AnySupport.toComparable(key));
return entry !== undefined ? entry.register.value : undefined;
};
/**
* Set the register at the given key to the given value.
*
* @function module:akkaserverless.replicatedentity.ReplicatedRegisterMap#set
* @param {module:akkaserverless.Serializable} key The key for the register.
* @param {module:akkaserverless.Serializable} value The new value for the register.
* @param {module:akkaserverless.replicatedentity.Clock} [clock=Clocks.DEFAULT] The register clock.
* @param {number} [customClockValue=0] Clock value when using custom clock, otherwise ignored.
* @returns {module:akkaserverless.replicatedentity.ReplicatedRegisterMap} This register map.
*/
this.set = function (
key,
value,
clock = Clocks.DEFAULT,
customClockValue = 0,
) {
this.getOrCreateRegister(key).setWithClock(value, clock, customClockValue);
return this;
};
/**
* Check whether this map contains a value of the given key.
*
* @function module:akkaserverless.replicatedentity.ReplicatedRegisterMap#has
* @param {module:akkaserverless.Serializable} key The key to check.
* @returns {boolean} True if this register map contains a value for the given key.
*/
this.has = function (key) {
return registers.has(AnySupport.toComparable(key));
};
/**
* The number of elements in this map.
*
* @name module:akkaserverless.replicatedentity.ReplicatedRegisterMap#size
* @type {number}
* @readonly
*/
Object.defineProperty(this, 'size', {
get: function () {
return registers.size;
},
});
/**
* Return an iterator of the keys of this register map.
*
* @function module:akkaserverless.replicatedentity.ReplicatedRegisterMap#keys
* @returns {IterableIterator<module:akkaserverless.Serializable>}
*/
this.keys = function () {
return iterators.map(registers.values(), (entry) => entry.key);
};
/**
* Delete the register at the given key.
*
* @function module:akkaserverless.replicatedentity.ReplicatedRegisterMap#delete
* @param {module:akkaserverless.Serializable} key The key to delete.
* @return {module:akkaserverless.replicatedentity.ReplicatedRegisterMap} This register map.
*/
this.delete = function (key) {
const comparableKey = AnySupport.toComparable(key);
if (registers.has(comparableKey)) {
registers.delete(comparableKey);
removed.set(comparableKey, key);
}
return this;
};
/**
* Clear all registers from this register map.
*
* @function module:akkaserverless.replicatedentity.ReplicatedRegisterMap#clear
* @return {module:akkaserverless.replicatedentity.ReplicatedRegisterMap} This register map.
*/
this.clear = function () {
if (registers.size > 0) {
cleared = true;
registers.clear();
removed.clear();
}
return this;
};
this.getOrCreateRegister = function (key) {
const comparableKey = AnySupport.toComparable(key);
const entry = registers.get(comparableKey);
if (entry) {
return entry.register;
} else {
const register = new ReplicatedRegister({});
registers.set(comparableKey, { key: key, register: register });
return register;
}
};
this.getAndResetDelta = function (initial) {
const updated = [];
registers.forEach(({ key: key, register: register }, comparableKey) => {
const delta = register.getAndResetDelta();
if (delta !== null) {
updated.push({
key: AnySupport.serialize(key, true, true),
delta: delta.register,
});
}
});
if (cleared || removed.size > 0 || updated.length > 0 || initial) {
const delta = {
replicatedRegisterMap: {
cleared: cleared,
removed: Array.from(removed.values()).map((key) =>
AnySupport.serialize(key, true, true),
),
updated: updated,
},
};
cleared = false;
removed.clear();
return delta;
} else {
return null;
}
};
this.applyDelta = function (delta, anySupport) {
if (!delta.replicatedRegisterMap) {
throw new Error(
util.format('Cannot apply delta %o to ReplicatedRegisterMap', delta),
);
}
if (delta.replicatedRegisterMap.cleared) {
registers.clear();
}
if (delta.replicatedRegisterMap.removed) {
delta.replicatedRegisterMap.removed.forEach((serializedKey) => {
const key = anySupport.deserialize(serializedKey);
const comparableKey = AnySupport.toComparable(key);
if (registers.has(comparableKey)) {
registers.delete(comparableKey);
} else {
debug('Key to delete [%o] is not in ReplicatedRegisterMap', key);
}
});
}
if (delta.replicatedRegisterMap.updated) {
delta.replicatedRegisterMap.updated.forEach((entry) => {
const key = anySupport.deserialize(entry.key);
this.getOrCreateRegister(key).applyDelta(
{ register: entry.delta },
anySupport,
);
});
}
};
this.toString = function () {
return (
'ReplicatedRegisterMap(' +
Array.from(registers.values())
.map((entry) => entry.key + ' -> ' + entry.register.value)
.join(', ') +
')'
);
};
}
module.exports = ReplicatedRegisterMap;