/var/www/qr4y.com/server/delivery/node_modules/@grpc/grpc-js/src
Edit: /var/www/qr4y.com/server/delivery/node_modules/@grpc/grpc-js/src/subchannel-pool.ts (5380B)
/*
* Copyright 2019 gRPC authors.
*
* 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.
*
*/
import { ChannelOptions, channelOptionsEqual } from './channel-options';
import { Subchannel } from './subchannel';
import {
SubchannelAddress,
subchannelAddressEqual,
} from './subchannel-address';
import { ChannelCredentials } from './channel-credentials';
import { GrpcUri, uriToString } from './uri-parser';
// 10 seconds in milliseconds. This value is arbitrary.
/**
* The amount of time in between checks for dropping subchannels that have no
* other references
*/
const REF_CHECK_INTERVAL = 10_000;
export class SubchannelPool {
private pool: {
[channelTarget: string]: Array<{
subchannelAddress: SubchannelAddress;
channelArguments: ChannelOptions;
channelCredentials: ChannelCredentials;
subchannel: Subchannel;
}>;
} = Object.create(null);
/**
* A timer of a task performing a periodic subchannel cleanup.
*/
private cleanupTimer: NodeJS.Timer | null = null;
/**
* A pool of subchannels use for making connections. Subchannels with the
* exact same parameters will be reused.
*/
constructor() {}
/**
* Unrefs all unused subchannels and cancels the cleanup task if all
* subchannels have been unrefed.
*/
unrefUnusedSubchannels(): void {
let allSubchannelsUnrefed = true;
/* These objects are created with Object.create(null), so they do not
* have a prototype, which means that for (... in ...) loops over them
* do not need to be filtered */
// eslint-disable-disable-next-line:forin
for (const channelTarget in this.pool) {
const subchannelObjArray = this.pool[channelTarget];
const refedSubchannels = subchannelObjArray.filter(
(value) => !value.subchannel.unrefIfOneRef()
);
if (refedSubchannels.length > 0) {
allSubchannelsUnrefed = false;
}
/* For each subchannel in the pool, try to unref it if it has
* exactly one ref (which is the ref from the pool itself). If that
* does happen, remove the subchannel from the pool */
this.pool[channelTarget] = refedSubchannels;
}
/* Currently we do not delete keys with empty values. If that results
* in significant memory usage we should change it. */
// Cancel the cleanup task if all subchannels have been unrefed.
if (allSubchannelsUnrefed && this.cleanupTimer !== null) {
clearInterval(this.cleanupTimer);
this.cleanupTimer = null;
}
}
/**
* Ensures that the cleanup task is spawned.
*/
ensureCleanupTask(): void {
if (this.cleanupTimer === null) {
this.cleanupTimer = setInterval(() => {
this.unrefUnusedSubchannels();
}, REF_CHECK_INTERVAL);
// Unref because this timer should not keep the event loop running.
// Call unref only if it exists to address electron/electron#21162
this.cleanupTimer.unref?.();
}
}
/**
* Get a subchannel if one already exists with exactly matching parameters.
* Otherwise, create and save a subchannel with those parameters.
* @param channelTarget
* @param subchannelTarget
* @param channelArguments
* @param channelCredentials
*/
getOrCreateSubchannel(
channelTargetUri: GrpcUri,
subchannelTarget: SubchannelAddress,
channelArguments: ChannelOptions,
channelCredentials: ChannelCredentials
): Subchannel {
this.ensureCleanupTask();
const channelTarget = uriToString(channelTargetUri);
if (channelTarget in this.pool) {
const subchannelObjArray = this.pool[channelTarget];
for (const subchannelObj of subchannelObjArray) {
if (
subchannelAddressEqual(
subchannelTarget,
subchannelObj.subchannelAddress
) &&
channelOptionsEqual(
channelArguments,
subchannelObj.channelArguments
) &&
channelCredentials._equals(subchannelObj.channelCredentials)
) {
return subchannelObj.subchannel;
}
}
}
// If we get here, no matching subchannel was found
const subchannel = new Subchannel(
channelTargetUri,
subchannelTarget,
channelArguments,
channelCredentials
);
if (!(channelTarget in this.pool)) {
this.pool[channelTarget] = [];
}
this.pool[channelTarget].push({
subchannelAddress: subchannelTarget,
channelArguments,
channelCredentials,
subchannel,
});
subchannel.ref();
return subchannel;
}
}
const globalSubchannelPool = new SubchannelPool();
/**
* Get either the global subchannel pool, or a new subchannel pool.
* @param global
*/
export function getSubchannelPool(global: boolean): SubchannelPool {
if (global) {
return globalSubchannelPool;
} else {
return new SubchannelPool();
}
}