xds: implement the top-level LB policy #7203
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…and implement the config parser.
…oup of child balancers to the Channel when handleResolvedAddresses is invoked.
…LE instead of INTERNAL error.
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| class ClusterManagerLoadBalancer extends LoadBalancer { | ||
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| @VisibleForTesting | ||
| static final int DELAYED_ACTION_DELETION_TIME_MINUTES = 15; |
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| @Override | ||
| public void updateBalancingState(ConnectivityState newState, SubchannelPicker newPicker) { | ||
| if (deactivated) { |
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Even if deactivated, should still update currentState and currentPicker, just not updateOverallBalancingState() (already guaranteed). The XdsRoutingLoadBalancer has the same issue.
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Good point. Fixed here.
| this.helper = checkNotNull(helper, "helper"); | ||
| this.syncContext = checkNotNull(helper.getSynchronizationContext(), "syncContext"); | ||
| this.timeService = checkNotNull(helper.getScheduledExecutorService(), "timeService"); | ||
| logger = XdsLogger.withLogId(InternalLogId.allocate("cds-lb", helper.getAuthority())); |
| syncContext.execute(new Runnable() { | ||
| @Override | ||
| public void run() { | ||
| childLbStates.get(name).lb.handleResolvedAddresses(childAddresses); |
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Declare variable for childLbStates.get(name) ahead of syncContext.execute(), otherwise childLbStates might have been mutated when `syncContext.execute() in extreme case.
Or just run childLbStates.get(name).lb.handleResolvedAddresses(childAddresses) inline at the end of this method.
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Good point, this turns out to be a programming practice. Thanks. Fixed. Will change it in XdsRoutingLoadBalancer as well (although it will go away after XdsConfigSelector, we want it to be correct in the release).
…ts config is updated in the parent balancer.
The top-level LB policy, which is an aggregator for CDS policies. It maintains the lifecycle of CDS LB policy instances. The pick argument taken from the Channel contains the information to determine which child CDS policy instance should the picking operation be delegated to. The implementation is similar to the action part of what we currently have in the routing policy. The existing routing policy will be refactored to two parts, with the route match part moved into ConfigSelector and action part being this top-level LB policy.
The top-level LB policy, which is an aggregator for CDS policies. It maintains the lifecycle of CDS LB policy instances. The pick argument taken from the Channel contains the information to determine which child CDS policy instance should the picking operation be delegated to.
The implementation is similar to the action part of what we currently have in the routing policy. The existing routing policy will be refactored to two parts, with the route match part moved into ConfigSelector and action part being this top-level LB policy.