diff options
| author | altaf-creator <dev@altafcreator.com> | 2025-11-16 19:08:29 +0800 |
|---|---|---|
| committer | altaf-creator <dev@altafcreator.com> | 2025-11-16 19:08:29 +0800 |
| commit | 434aa8343fdcbb4d5002f934979913c099489bee (patch) | |
| tree | 55bab4ec5a6151be57797d34f61faf5ea744471b /frontend-old/node_modules/@grpc/grpc-js/src/load-balancer-pick-first.ts | |
| parent | 893c388d4e99442a36005e5971a87730623f946e (diff) | |
sdk, del
Diffstat (limited to 'frontend-old/node_modules/@grpc/grpc-js/src/load-balancer-pick-first.ts')
| -rw-r--r-- | frontend-old/node_modules/@grpc/grpc-js/src/load-balancer-pick-first.ts | 487 |
1 files changed, 0 insertions, 487 deletions
diff --git a/frontend-old/node_modules/@grpc/grpc-js/src/load-balancer-pick-first.ts b/frontend-old/node_modules/@grpc/grpc-js/src/load-balancer-pick-first.ts deleted file mode 100644 index 75c9d4c..0000000 --- a/frontend-old/node_modules/@grpc/grpc-js/src/load-balancer-pick-first.ts +++ /dev/null @@ -1,487 +0,0 @@ -/* - * 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 { - LoadBalancer, - ChannelControlHelper, - LoadBalancingConfig, - registerDefaultLoadBalancerType, - registerLoadBalancerType, -} from './load-balancer'; -import { ConnectivityState } from './connectivity-state'; -import { - QueuePicker, - Picker, - PickArgs, - CompletePickResult, - PickResultType, - UnavailablePicker, -} from './picker'; -import { SubchannelAddress } from './subchannel-address'; -import * as logging from './logging'; -import { LogVerbosity } from './constants'; -import { - SubchannelInterface, - ConnectivityStateListener, -} from './subchannel-interface'; - -const TRACER_NAME = 'pick_first'; - -function trace(text: string): void { - logging.trace(LogVerbosity.DEBUG, TRACER_NAME, text); -} - -const TYPE_NAME = 'pick_first'; - -/** - * Delay after starting a connection on a subchannel before starting a - * connection on the next subchannel in the list, for Happy Eyeballs algorithm. - */ -const CONNECTION_DELAY_INTERVAL_MS = 250; - -export class PickFirstLoadBalancingConfig implements LoadBalancingConfig { - constructor(private readonly shuffleAddressList: boolean) {} - - getLoadBalancerName(): string { - return TYPE_NAME; - } - - toJsonObject(): object { - return { - [TYPE_NAME]: { - shuffleAddressList: this.shuffleAddressList, - }, - }; - } - - getShuffleAddressList() { - return this.shuffleAddressList; - } - - // eslint-disable-next-line @typescript-eslint/no-explicit-any - static createFromJson(obj: any) { - if ( - 'shuffleAddressList' in obj && - !(typeof obj.shuffleAddressList === 'boolean') - ) { - throw new Error( - 'pick_first config field shuffleAddressList must be a boolean if provided' - ); - } - return new PickFirstLoadBalancingConfig(obj.shuffleAddressList === true); - } -} - -/** - * Picker for a `PickFirstLoadBalancer` in the READY state. Always returns the - * picked subchannel. - */ -class PickFirstPicker implements Picker { - constructor(private subchannel: SubchannelInterface) {} - - pick(pickArgs: PickArgs): CompletePickResult { - return { - pickResultType: PickResultType.COMPLETE, - subchannel: this.subchannel, - status: null, - onCallStarted: null, - onCallEnded: null, - }; - } -} - -interface SubchannelChild { - subchannel: SubchannelInterface; - hasReportedTransientFailure: boolean; -} - -/** - * Return a new array with the elements of the input array in a random order - * @param list The input array - * @returns A shuffled array of the elements of list - */ -export function shuffled<T>(list: T[]): T[] { - const result = list.slice(); - for (let i = result.length - 1; i > 1; i--) { - const j = Math.floor(Math.random() * (i + 1)); - const temp = result[i]; - result[i] = result[j]; - result[j] = temp; - } - return result; -} - -export class PickFirstLoadBalancer implements LoadBalancer { - /** - * The list of subchannels this load balancer is currently attempting to - * connect to. - */ - private children: SubchannelChild[] = []; - /** - * The current connectivity state of the load balancer. - */ - private currentState: ConnectivityState = ConnectivityState.IDLE; - /** - * The index within the `subchannels` array of the subchannel with the most - * recently started connection attempt. - */ - private currentSubchannelIndex = 0; - /** - * The currently picked subchannel used for making calls. Populated if - * and only if the load balancer's current state is READY. In that case, - * the subchannel's current state is also READY. - */ - private currentPick: SubchannelInterface | null = null; - /** - * Listener callback attached to each subchannel in the `subchannels` list - * while establishing a connection. - */ - private subchannelStateListener: ConnectivityStateListener = ( - subchannel, - previousState, - newState, - keepaliveTime, - errorMessage - ) => { - this.onSubchannelStateUpdate(subchannel, previousState, newState, errorMessage); - }; - /** - * Timer reference for the timer tracking when to start - */ - private connectionDelayTimeout: NodeJS.Timeout; - - private triedAllSubchannels = false; - - /** - * The LB policy enters sticky TRANSIENT_FAILURE mode when all - * subchannels have failed to connect at least once, and it stays in that - * mode until a connection attempt is successful. While in sticky TF mode, - * the LB policy continuously attempts to connect to all of its subchannels. - */ - private stickyTransientFailureMode = false; - - /** - * Indicates whether we called channelControlHelper.requestReresolution since - * the last call to updateAddressList - */ - private requestedResolutionSinceLastUpdate = false; - - /** - * The most recent error reported by any subchannel as it transitioned to - * TRANSIENT_FAILURE. - */ - private lastError: string | null = null; - - private latestAddressList: SubchannelAddress[] | null = null; - - /** - * Load balancer that attempts to connect to each backend in the address list - * in order, and picks the first one that connects, using it for every - * request. - * @param channelControlHelper `ChannelControlHelper` instance provided by - * this load balancer's owner. - */ - constructor(private readonly channelControlHelper: ChannelControlHelper) { - this.connectionDelayTimeout = setTimeout(() => {}, 0); - clearTimeout(this.connectionDelayTimeout); - } - - private allChildrenHaveReportedTF(): boolean { - return this.children.every(child => child.hasReportedTransientFailure); - } - - private calculateAndReportNewState() { - if (this.currentPick) { - this.updateState( - ConnectivityState.READY, - new PickFirstPicker(this.currentPick) - ); - } else if (this.children.length === 0) { - this.updateState(ConnectivityState.IDLE, new QueuePicker(this)); - } else { - if (this.stickyTransientFailureMode) { - this.updateState( - ConnectivityState.TRANSIENT_FAILURE, - new UnavailablePicker({details: `No connection established. Last error: ${this.lastError}`}) - ); - } else { - this.updateState(ConnectivityState.CONNECTING, new QueuePicker(this)); - } - } - } - - private requestReresolution() { - this.requestedResolutionSinceLastUpdate = true; - this.channelControlHelper.requestReresolution(); - } - - private maybeEnterStickyTransientFailureMode() { - if (!this.allChildrenHaveReportedTF()) { - return; - } - if (!this.requestedResolutionSinceLastUpdate) { - /* Each time we get an update we reset each subchannel's - * hasReportedTransientFailure flag, so the next time we get to this - * point after that, each subchannel has reported TRANSIENT_FAILURE - * at least once since then. That is the trigger for requesting - * reresolution, whether or not the LB policy is already in sticky TF - * mode. */ - this.requestReresolution(); - } - if (this.stickyTransientFailureMode) { - return; - } - this.stickyTransientFailureMode = true; - for (const { subchannel } of this.children) { - subchannel.startConnecting(); - } - this.calculateAndReportNewState(); - } - - private removeCurrentPick() { - if (this.currentPick !== null) { - /* Unref can cause a state change, which can cause a change in the value - * of this.currentPick, so we hold a local reference to make sure that - * does not impact this function. */ - const currentPick = this.currentPick; - this.currentPick = null; - currentPick.unref(); - currentPick.removeConnectivityStateListener(this.subchannelStateListener); - this.channelControlHelper.removeChannelzChild( - currentPick.getChannelzRef() - ); - } - } - - private onSubchannelStateUpdate( - subchannel: SubchannelInterface, - previousState: ConnectivityState, - newState: ConnectivityState, - errorMessage?: string - ) { - if (this.currentPick?.realSubchannelEquals(subchannel)) { - if (newState !== ConnectivityState.READY) { - this.removeCurrentPick(); - this.calculateAndReportNewState(); - this.requestReresolution(); - } - return; - } - for (const [index, child] of this.children.entries()) { - if (subchannel.realSubchannelEquals(child.subchannel)) { - if (newState === ConnectivityState.READY) { - this.pickSubchannel(child.subchannel); - } - if (newState === ConnectivityState.TRANSIENT_FAILURE) { - child.hasReportedTransientFailure = true; - if (errorMessage) { - this.lastError = errorMessage; - } - this.maybeEnterStickyTransientFailureMode(); - if (index === this.currentSubchannelIndex) { - this.startNextSubchannelConnecting(index + 1); - } - } - child.subchannel.startConnecting(); - return; - } - } - } - - private startNextSubchannelConnecting(startIndex: number) { - clearTimeout(this.connectionDelayTimeout); - if (this.triedAllSubchannels) { - return; - } - for (const [index, child] of this.children.entries()) { - if (index >= startIndex) { - const subchannelState = child.subchannel.getConnectivityState(); - if ( - subchannelState === ConnectivityState.IDLE || - subchannelState === ConnectivityState.CONNECTING - ) { - this.startConnecting(index); - return; - } - } - } - this.triedAllSubchannels = true; - this.maybeEnterStickyTransientFailureMode(); - } - - /** - * Have a single subchannel in the `subchannels` list start connecting. - * @param subchannelIndex The index into the `subchannels` list. - */ - private startConnecting(subchannelIndex: number) { - clearTimeout(this.connectionDelayTimeout); - this.currentSubchannelIndex = subchannelIndex; - if ( - this.children[subchannelIndex].subchannel.getConnectivityState() === - ConnectivityState.IDLE - ) { - trace( - 'Start connecting to subchannel with address ' + - this.children[subchannelIndex].subchannel.getAddress() - ); - process.nextTick(() => { - this.children[subchannelIndex]?.subchannel.startConnecting(); - }); - } - this.connectionDelayTimeout = setTimeout(() => { - this.startNextSubchannelConnecting(subchannelIndex + 1); - }, CONNECTION_DELAY_INTERVAL_MS).unref?.(); - } - - private pickSubchannel(subchannel: SubchannelInterface) { - if (this.currentPick && subchannel.realSubchannelEquals(this.currentPick)) { - return; - } - trace('Pick subchannel with address ' + subchannel.getAddress()); - this.stickyTransientFailureMode = false; - if (this.currentPick !== null) { - this.currentPick.unref(); - this.channelControlHelper.removeChannelzChild( - this.currentPick.getChannelzRef() - ); - this.currentPick.removeConnectivityStateListener( - this.subchannelStateListener - ); - } - this.currentPick = subchannel; - subchannel.ref(); - this.channelControlHelper.addChannelzChild(subchannel.getChannelzRef()); - this.resetSubchannelList(); - clearTimeout(this.connectionDelayTimeout); - this.calculateAndReportNewState(); - } - - private updateState(newState: ConnectivityState, picker: Picker) { - trace( - ConnectivityState[this.currentState] + - ' -> ' + - ConnectivityState[newState] - ); - this.currentState = newState; - this.channelControlHelper.updateState(newState, picker); - } - - private resetSubchannelList() { - for (const child of this.children) { - if (!(this.currentPick && child.subchannel.realSubchannelEquals(this.currentPick))) { - /* The connectivity state listener is the same whether the subchannel - * is in the list of children or it is the currentPick, so if it is in - * both, removing it here would cause problems. In particular, that - * always happens immediately after the subchannel is picked. */ - child.subchannel.removeConnectivityStateListener( - this.subchannelStateListener - ); - } - /* Refs are counted independently for the children list and the - * currentPick, so we call unref whether or not the child is the - * currentPick. Channelz child references are also refcounted, so - * removeChannelzChild can be handled the same way. */ - child.subchannel.unref(); - this.channelControlHelper.removeChannelzChild( - child.subchannel.getChannelzRef() - ); - } - this.currentSubchannelIndex = 0; - this.children = []; - this.triedAllSubchannels = false; - this.requestedResolutionSinceLastUpdate = false; - } - - private connectToAddressList(addressList: SubchannelAddress[]) { - const newChildrenList = addressList.map(address => ({ - subchannel: this.channelControlHelper.createSubchannel(address, {}), - hasReportedTransientFailure: false, - })); - /* Ref each subchannel before resetting the list, to ensure that - * subchannels shared between the list don't drop to 0 refs during the - * transition. */ - for (const { subchannel } of newChildrenList) { - subchannel.ref(); - this.channelControlHelper.addChannelzChild(subchannel.getChannelzRef()); - } - this.resetSubchannelList(); - this.children = newChildrenList; - for (const { subchannel } of this.children) { - subchannel.addConnectivityStateListener(this.subchannelStateListener); - if (subchannel.getConnectivityState() === ConnectivityState.READY) { - this.pickSubchannel(subchannel); - return; - } - } - for (const child of this.children) { - if ( - child.subchannel.getConnectivityState() === - ConnectivityState.TRANSIENT_FAILURE - ) { - child.hasReportedTransientFailure = true; - } - } - this.startNextSubchannelConnecting(0); - this.calculateAndReportNewState(); - } - - updateAddressList( - addressList: SubchannelAddress[], - lbConfig: LoadBalancingConfig - ): void { - if (!(lbConfig instanceof PickFirstLoadBalancingConfig)) { - return; - } - /* Previously, an update would be discarded if it was identical to the - * previous update, to minimize churn. Now the DNS resolver is - * rate-limited, so that is less of a concern. */ - if (lbConfig.getShuffleAddressList()) { - addressList = shuffled(addressList); - } - this.latestAddressList = addressList; - this.connectToAddressList(addressList); - } - - exitIdle() { - if (this.currentState === ConnectivityState.IDLE && this.latestAddressList) { - this.connectToAddressList(this.latestAddressList); - } - } - - resetBackoff() { - /* The pick first load balancer does not have a connection backoff, so this - * does nothing */ - } - - destroy() { - this.resetSubchannelList(); - this.removeCurrentPick(); - } - - getTypeName(): string { - return TYPE_NAME; - } -} - -export function setup(): void { - registerLoadBalancerType( - TYPE_NAME, - PickFirstLoadBalancer, - PickFirstLoadBalancingConfig - ); - registerDefaultLoadBalancerType(TYPE_NAME); -} |
