304 lines
13 KiB
JavaScript
304 lines
13 KiB
JavaScript
"use strict";
|
|
/*
|
|
* 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.
|
|
*
|
|
*/
|
|
Object.defineProperty(exports, "__esModule", { value: true });
|
|
exports.ResolvingLoadBalancer = void 0;
|
|
const load_balancer_1 = require("./load-balancer");
|
|
const service_config_1 = require("./service-config");
|
|
const connectivity_state_1 = require("./connectivity-state");
|
|
const resolver_1 = require("./resolver");
|
|
const picker_1 = require("./picker");
|
|
const backoff_timeout_1 = require("./backoff-timeout");
|
|
const constants_1 = require("./constants");
|
|
const metadata_1 = require("./metadata");
|
|
const logging = require("./logging");
|
|
const constants_2 = require("./constants");
|
|
const uri_parser_1 = require("./uri-parser");
|
|
const load_balancer_child_handler_1 = require("./load-balancer-child-handler");
|
|
const TRACER_NAME = 'resolving_load_balancer';
|
|
function trace(text) {
|
|
logging.trace(constants_2.LogVerbosity.DEBUG, TRACER_NAME, text);
|
|
}
|
|
/**
|
|
* Name match levels in order from most to least specific. This is the order in
|
|
* which searches will be performed.
|
|
*/
|
|
const NAME_MATCH_LEVEL_ORDER = [
|
|
'SERVICE_AND_METHOD',
|
|
'SERVICE',
|
|
'EMPTY',
|
|
];
|
|
function hasMatchingName(service, method, methodConfig, matchLevel) {
|
|
for (const name of methodConfig.name) {
|
|
switch (matchLevel) {
|
|
case 'EMPTY':
|
|
if (!name.service && !name.method) {
|
|
return true;
|
|
}
|
|
break;
|
|
case 'SERVICE':
|
|
if (name.service === service && !name.method) {
|
|
return true;
|
|
}
|
|
break;
|
|
case 'SERVICE_AND_METHOD':
|
|
if (name.service === service && name.method === method) {
|
|
return true;
|
|
}
|
|
}
|
|
}
|
|
return false;
|
|
}
|
|
function findMatchingConfig(service, method, methodConfigs, matchLevel) {
|
|
for (const config of methodConfigs) {
|
|
if (hasMatchingName(service, method, config, matchLevel)) {
|
|
return config;
|
|
}
|
|
}
|
|
return null;
|
|
}
|
|
function getDefaultConfigSelector(serviceConfig) {
|
|
return function defaultConfigSelector(methodName, metadata) {
|
|
var _a, _b;
|
|
const splitName = methodName.split('/').filter(x => x.length > 0);
|
|
const service = (_a = splitName[0]) !== null && _a !== void 0 ? _a : '';
|
|
const method = (_b = splitName[1]) !== null && _b !== void 0 ? _b : '';
|
|
if (serviceConfig && serviceConfig.methodConfig) {
|
|
/* Check for the following in order, and return the first method
|
|
* config that matches:
|
|
* 1. A name that exactly matches the service and method
|
|
* 2. A name with no method set that matches the service
|
|
* 3. An empty name
|
|
*/
|
|
for (const matchLevel of NAME_MATCH_LEVEL_ORDER) {
|
|
const matchingConfig = findMatchingConfig(service, method, serviceConfig.methodConfig, matchLevel);
|
|
if (matchingConfig) {
|
|
return {
|
|
methodConfig: matchingConfig,
|
|
pickInformation: {},
|
|
status: constants_1.Status.OK,
|
|
dynamicFilterFactories: [],
|
|
};
|
|
}
|
|
}
|
|
}
|
|
return {
|
|
methodConfig: { name: [] },
|
|
pickInformation: {},
|
|
status: constants_1.Status.OK,
|
|
dynamicFilterFactories: [],
|
|
};
|
|
};
|
|
}
|
|
class ResolvingLoadBalancer {
|
|
/**
|
|
* Wrapper class that behaves like a `LoadBalancer` and also handles name
|
|
* resolution internally.
|
|
* @param target The address of the backend to connect to.
|
|
* @param channelControlHelper `ChannelControlHelper` instance provided by
|
|
* this load balancer's owner.
|
|
* @param defaultServiceConfig The default service configuration to be used
|
|
* if none is provided by the name resolver. A `null` value indicates
|
|
* that the default behavior should be the default unconfigured behavior.
|
|
* In practice, that means using the "pick first" load balancer
|
|
* implmentation
|
|
*/
|
|
constructor(target, channelControlHelper, channelOptions, onSuccessfulResolution, onFailedResolution) {
|
|
this.target = target;
|
|
this.channelControlHelper = channelControlHelper;
|
|
this.onSuccessfulResolution = onSuccessfulResolution;
|
|
this.onFailedResolution = onFailedResolution;
|
|
this.latestChildState = connectivity_state_1.ConnectivityState.IDLE;
|
|
this.latestChildPicker = new picker_1.QueuePicker(this);
|
|
/**
|
|
* This resolving load balancer's current connectivity state.
|
|
*/
|
|
this.currentState = connectivity_state_1.ConnectivityState.IDLE;
|
|
/**
|
|
* The service config object from the last successful resolution, if
|
|
* available. A value of null indicates that we have not yet received a valid
|
|
* service config from the resolver.
|
|
*/
|
|
this.previousServiceConfig = null;
|
|
/**
|
|
* Indicates whether we should attempt to resolve again after the backoff
|
|
* timer runs out.
|
|
*/
|
|
this.continueResolving = false;
|
|
if (channelOptions['grpc.service_config']) {
|
|
this.defaultServiceConfig = (0, service_config_1.validateServiceConfig)(JSON.parse(channelOptions['grpc.service_config']));
|
|
}
|
|
else {
|
|
this.defaultServiceConfig = {
|
|
loadBalancingConfig: [],
|
|
methodConfig: [],
|
|
};
|
|
}
|
|
this.updateState(connectivity_state_1.ConnectivityState.IDLE, new picker_1.QueuePicker(this));
|
|
this.childLoadBalancer = new load_balancer_child_handler_1.ChildLoadBalancerHandler({
|
|
createSubchannel: channelControlHelper.createSubchannel.bind(channelControlHelper),
|
|
requestReresolution: () => {
|
|
/* If the backoffTimeout is running, we're still backing off from
|
|
* making resolve requests, so we shouldn't make another one here.
|
|
* In that case, the backoff timer callback will call
|
|
* updateResolution */
|
|
if (this.backoffTimeout.isRunning()) {
|
|
trace('requestReresolution delayed by backoff timer until ' + this.backoffTimeout.getEndTime().toISOString());
|
|
this.continueResolving = true;
|
|
}
|
|
else {
|
|
this.updateResolution();
|
|
}
|
|
},
|
|
updateState: (newState, picker) => {
|
|
this.latestChildState = newState;
|
|
this.latestChildPicker = picker;
|
|
this.updateState(newState, picker);
|
|
},
|
|
addChannelzChild: channelControlHelper.addChannelzChild.bind(channelControlHelper),
|
|
removeChannelzChild: channelControlHelper.removeChannelzChild.bind(channelControlHelper),
|
|
});
|
|
this.innerResolver = (0, resolver_1.createResolver)(target, {
|
|
onSuccessfulResolution: (addressList, serviceConfig, serviceConfigError, configSelector, attributes) => {
|
|
var _a;
|
|
this.backoffTimeout.stop();
|
|
this.backoffTimeout.reset();
|
|
let workingServiceConfig = null;
|
|
/* This first group of conditionals implements the algorithm described
|
|
* in https://github.com/grpc/proposal/blob/master/A21-service-config-error-handling.md
|
|
* in the section called "Behavior on receiving a new gRPC Config".
|
|
*/
|
|
if (serviceConfig === null) {
|
|
// Step 4 and 5
|
|
if (serviceConfigError === null) {
|
|
// Step 5
|
|
this.previousServiceConfig = null;
|
|
workingServiceConfig = this.defaultServiceConfig;
|
|
}
|
|
else {
|
|
// Step 4
|
|
if (this.previousServiceConfig === null) {
|
|
// Step 4.ii
|
|
this.handleResolutionFailure(serviceConfigError);
|
|
}
|
|
else {
|
|
// Step 4.i
|
|
workingServiceConfig = this.previousServiceConfig;
|
|
}
|
|
}
|
|
}
|
|
else {
|
|
// Step 3
|
|
workingServiceConfig = serviceConfig;
|
|
this.previousServiceConfig = serviceConfig;
|
|
}
|
|
const workingConfigList = (_a = workingServiceConfig === null || workingServiceConfig === void 0 ? void 0 : workingServiceConfig.loadBalancingConfig) !== null && _a !== void 0 ? _a : [];
|
|
const loadBalancingConfig = (0, load_balancer_1.getFirstUsableConfig)(workingConfigList, true);
|
|
if (loadBalancingConfig === null) {
|
|
// There were load balancing configs but none are supported. This counts as a resolution failure
|
|
this.handleResolutionFailure({
|
|
code: constants_1.Status.UNAVAILABLE,
|
|
details: 'All load balancer options in service config are not compatible',
|
|
metadata: new metadata_1.Metadata(),
|
|
});
|
|
return;
|
|
}
|
|
this.childLoadBalancer.updateAddressList(addressList, loadBalancingConfig, attributes);
|
|
const finalServiceConfig = workingServiceConfig !== null && workingServiceConfig !== void 0 ? workingServiceConfig : this.defaultServiceConfig;
|
|
this.onSuccessfulResolution(finalServiceConfig, configSelector !== null && configSelector !== void 0 ? configSelector : getDefaultConfigSelector(finalServiceConfig));
|
|
},
|
|
onError: (error) => {
|
|
this.handleResolutionFailure(error);
|
|
},
|
|
}, channelOptions);
|
|
const backoffOptions = {
|
|
initialDelay: channelOptions['grpc.initial_reconnect_backoff_ms'],
|
|
maxDelay: channelOptions['grpc.max_reconnect_backoff_ms'],
|
|
};
|
|
this.backoffTimeout = new backoff_timeout_1.BackoffTimeout(() => {
|
|
if (this.continueResolving) {
|
|
this.updateResolution();
|
|
this.continueResolving = false;
|
|
}
|
|
else {
|
|
this.updateState(this.latestChildState, this.latestChildPicker);
|
|
}
|
|
}, backoffOptions);
|
|
this.backoffTimeout.unref();
|
|
}
|
|
updateResolution() {
|
|
this.innerResolver.updateResolution();
|
|
if (this.currentState === connectivity_state_1.ConnectivityState.IDLE) {
|
|
this.updateState(connectivity_state_1.ConnectivityState.CONNECTING, new picker_1.QueuePicker(this));
|
|
}
|
|
this.backoffTimeout.runOnce();
|
|
}
|
|
updateState(connectivityState, picker) {
|
|
trace((0, uri_parser_1.uriToString)(this.target) +
|
|
' ' +
|
|
connectivity_state_1.ConnectivityState[this.currentState] +
|
|
' -> ' +
|
|
connectivity_state_1.ConnectivityState[connectivityState]);
|
|
// Ensure that this.exitIdle() is called by the picker
|
|
if (connectivityState === connectivity_state_1.ConnectivityState.IDLE) {
|
|
picker = new picker_1.QueuePicker(this);
|
|
}
|
|
this.currentState = connectivityState;
|
|
this.channelControlHelper.updateState(connectivityState, picker);
|
|
}
|
|
handleResolutionFailure(error) {
|
|
if (this.latestChildState === connectivity_state_1.ConnectivityState.IDLE) {
|
|
this.updateState(connectivity_state_1.ConnectivityState.TRANSIENT_FAILURE, new picker_1.UnavailablePicker(error));
|
|
this.onFailedResolution(error);
|
|
}
|
|
}
|
|
exitIdle() {
|
|
if (this.currentState === connectivity_state_1.ConnectivityState.IDLE ||
|
|
this.currentState === connectivity_state_1.ConnectivityState.TRANSIENT_FAILURE) {
|
|
if (this.backoffTimeout.isRunning()) {
|
|
this.continueResolving = true;
|
|
}
|
|
else {
|
|
this.updateResolution();
|
|
}
|
|
}
|
|
this.childLoadBalancer.exitIdle();
|
|
}
|
|
updateAddressList(addressList, lbConfig) {
|
|
throw new Error('updateAddressList not supported on ResolvingLoadBalancer');
|
|
}
|
|
resetBackoff() {
|
|
this.backoffTimeout.reset();
|
|
this.childLoadBalancer.resetBackoff();
|
|
}
|
|
destroy() {
|
|
this.childLoadBalancer.destroy();
|
|
this.innerResolver.destroy();
|
|
this.backoffTimeout.reset();
|
|
this.backoffTimeout.stop();
|
|
this.latestChildState = connectivity_state_1.ConnectivityState.IDLE;
|
|
this.latestChildPicker = new picker_1.QueuePicker(this);
|
|
this.currentState = connectivity_state_1.ConnectivityState.IDLE;
|
|
this.previousServiceConfig = null;
|
|
this.continueResolving = false;
|
|
}
|
|
getTypeName() {
|
|
return 'resolving_load_balancer';
|
|
}
|
|
}
|
|
exports.ResolvingLoadBalancer = ResolvingLoadBalancer;
|
|
//# sourceMappingURL=resolving-load-balancer.js.map
|