FrankChen021 commented on code in PR #19374: URL: https://github.com/apache/druid/pull/19374#discussion_r3141594208
########## server/src/main/java/org/apache/druid/server/coordinator/rules/PartialLoadRule.java: ########## @@ -0,0 +1,113 @@ +/* + * Licensed to the Apache Software Foundation (ASF) under one + * or more contributor license agreements. See the NOTICE file + * distributed with this work for additional information + * regarding copyright ownership. The ASF licenses this file + * to you 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. + */ + +package org.apache.druid.server.coordinator.rules; + +import com.fasterxml.jackson.annotation.JsonProperty; +import org.apache.druid.common.config.Configs; +import org.apache.druid.error.InvalidInput; +import org.apache.druid.timeline.DataSegment; +import org.joda.time.DateTime; + +import javax.annotation.Nullable; +import java.util.Map; +import java.util.Objects; + +/** + * Base class for rules that load only a subset of a segment on a tier. Pairs a {@link PartialLoadMatcher} (which + * produces the wrapped load-spec wire form and an accounting fingerprint when it applies to a segment) with a + * {@link CannotMatchBehavior} that controls whether the rule falls through or full-loads when the matcher does not + * apply. + */ +public abstract class PartialLoadRule extends LoadRule +{ + private final PartialLoadMatcher matcher; + private final CannotMatchBehavior onCannotMatch; + + protected PartialLoadRule( + Map<String, Integer> tieredReplicants, + @Nullable Boolean useDefaultTierForNull, + PartialLoadMatcher matcher, + @Nullable CannotMatchBehavior onCannotMatch + ) + { + super(tieredReplicants, useDefaultTierForNull); + if (matcher == null) { + throw InvalidInput.exception("matcher must not be null for a partial load rule"); + } + this.matcher = matcher; + this.onCannotMatch = Configs.valueOrDefault(onCannotMatch, CannotMatchBehavior.FULL_LOAD); + } + Review Comment: P1 Partial rule fall-through is invisible to handoff checks appliesTo returns false for a partial rule whose matcher cannot match and whose onCannotMatch is FALL_THROUGH. Handoff/readiness code that only asks whether the rule applies to the segment interval can therefore miss that this rule intentionally falls through to a later full-load rule, and can conclude that no load rule covers the segment. A realtime task for a segment without matching projections can then wait forever even though the cascade would load it through the following rule. The rule-selection path used by handoff needs to evaluate the same matcher/fall-through semantics as the coordinator cascade, not just interval applicability. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected] --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
