imbajin commented on code in PR #3331: URL: https://github.com/apache/hugegraph/pull/3331#discussion_r4273924527
########## hugegraph-server/hugegraph-core/src/main/java/org/apache/hugegraph/LoadingMode.java: ########## @@ -0,0 +1,177 @@ +/* + * 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.hugegraph; + +import java.util.HashMap; +import java.util.Map; +import java.util.Objects; +import java.util.UUID; + +import org.apache.hugegraph.type.define.GraphMode; +import org.apache.hugegraph.util.E; +import org.apache.hugegraph.util.Log; +import org.slf4j.Logger; + +import com.google.common.collect.ImmutableMap; + +/** Same graph-instance ownership; this state is neither persisted nor distributed. */ +public final class LoadingMode { + + private static final Logger LOG = Log.logger(LoadingMode.class); + + private static final int MAX_RELEASED = 1024; + + private final String instance = UUID.randomUUID().toString(); + private final Map<String, String> active = new HashMap<>(); + private final Map<String, String> released = new HashMap<>(); + private long epoch; + private long revision; + private volatile GraphMode mode = GraphMode.NONE; + + public GraphMode mode() { + return this.mode; + } + + public synchronized void mode(GraphMode mode) { + Objects.requireNonNull(mode, "mode"); + checkState(this.active.isEmpty(), "Loading owners are active; release them before setting graph mode"); + if (this.mode != mode) { Review Comment: ⚠️ A successful same value legacy `LOADING` write leaves the recovery revision unchanged. If an administrator reads revision R while the graph is already `LOADING`, a legacy Loader can start with `PUT /mode` and keep R unchanged; recovery with that snapshot then passes and sets the mode to `NONE` during the new import. Advance the revision on every successful setter call, including same value writes, and cover this interleaving. ########## hugegraph-server/hugegraph-core/src/main/java/org/apache/hugegraph/LoadingMode.java: ########## @@ -0,0 +1,177 @@ +/* + * 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.hugegraph; + +import java.util.HashMap; +import java.util.Map; +import java.util.Objects; +import java.util.UUID; + +import org.apache.hugegraph.type.define.GraphMode; +import org.apache.hugegraph.util.E; +import org.apache.hugegraph.util.Log; +import org.slf4j.Logger; + +import com.google.common.collect.ImmutableMap; + +/** Same graph-instance ownership; this state is neither persisted nor distributed. */ +public final class LoadingMode { + + private static final Logger LOG = Log.logger(LoadingMode.class); + + private static final int MAX_RELEASED = 1024; + + private final String instance = UUID.randomUUID().toString(); + private final Map<String, String> active = new HashMap<>(); + private final Map<String, String> released = new HashMap<>(); + private long epoch; + private long revision; + private volatile GraphMode mode = GraphMode.NONE; + + public GraphMode mode() { + return this.mode; + } + + public synchronized void mode(GraphMode mode) { + Objects.requireNonNull(mode, "mode"); + checkState(this.active.isEmpty(), "Loading owners are active; release them before setting graph mode"); + if (this.mode != mode) { + this.advanceRevision(); + } + this.mode = mode; + } + + public synchronized Map<String, Object> capability() { + return ImmutableMap.of("protocol", 1, "instance", this.instance, "epoch", this.epoch, + "revision", this.revision); + } + + public synchronized Map<String, Object> recover(String instance, long epoch, long revision) { + E.checkArgument(this.instance.equals(instance), "Loading owner belongs to another graph instance"); + E.checkArgument(epoch >= 0 && revision >= 0, "Invalid loading recovery epoch or revision"); + checkState(epoch == this.epoch && revision == this.revision, + "Loading state changed; inspect it before recovery"); + checkState(this.epoch < Long.MAX_VALUE, "Loading owner epoch exhausted"); + GraphMode previousMode = this.mode; + int clearedOwners = this.active.size(); + this.advanceRevision(); + this.epoch++; + this.active.clear(); + this.released.clear(); + this.mode = GraphMode.NONE; + this.logChange("recover", previousMode, clearedOwners); + return ImmutableMap.<String, Object>builder().putAll(this.capability()) + .put("state", "recovered").put("mode", this.mode).build(); + } + + public synchronized Map<String, Object> update(String action, String instance, long epoch, + String token, String principal) { + E.checkArgument("acquire".equals(action) || "release".equals(action), + "Loading owner action must be acquire or release"); + E.checkArgument(this.instance.equals(instance), "Loading owner belongs to another graph instance"); + E.checkArgument(epoch >= 0 && epoch <= this.epoch, "Invalid loading owner epoch"); + E.checkArgument(token != null && token.length() == 36 && UUID.fromString(token).toString().equals(token), + "Loading owner token must be a canonical UUID"); + Objects.requireNonNull(principal, "principal"); + GraphMode previousMode = this.mode; + String key = epoch + "/" + token; + String owner = this.active.get(key); + if (owner != null) { + checkState(owner.equals(principal), "Loading owner belongs to another authenticated principal"); + if ("acquire".equals(action)) { + return this.receipt(epoch, token, "active"); + } + // Exhaustion must fail before changing an active registration. + checkState(epoch != this.epoch || this.released.size() < MAX_RELEASED || + this.epoch < Long.MAX_VALUE, "Loading owner epoch exhausted"); + this.advanceRevision(); + this.active.remove(key); + if (this.active.isEmpty()) { + this.mode = GraphMode.NONE; + } + } else if ("acquire".equals(action)) { + if (epoch < this.epoch || this.released.containsKey(key)) { + return this.receipt(epoch, token, "released"); + } + checkState(this.active.isEmpty() ? this.mode == GraphMode.NONE : this.mode == GraphMode.LOADING, + "Cannot acquire loading ownership of manually set graph mode %s", this.mode); + this.advanceRevision(); + this.active.put(key, principal); Review Comment: ⚠️ Every new owner token is inserted into `active`, but this per graph map has no cardinality bound. A STATUS WRITE caller can submit fresh UUIDs without releasing them, pinning the graph in `LOADING` and growing memory and INFO log output until an administrator recovers it; add a bounded admission limit before insertion. -- 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]
