reswqa commented on code in PR #29: URL: https://github.com/apache/flink-connector-pulsar/pull/29#discussion_r1108073067
########## flink-connector-pulsar/src/main/java/org/apache/flink/connector/pulsar/common/handler/PulsarAdminInvocationHandler.java: ########## @@ -0,0 +1,152 @@ +/* + * 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.flink.connector.pulsar.common.handler; + +import org.apache.flink.connector.pulsar.common.config.PulsarConfiguration; + +import org.apache.flink.shaded.guava30.com.google.common.util.concurrent.RateLimiter; + +import org.apache.pulsar.client.admin.PulsarAdmin; +import org.apache.pulsar.client.admin.PulsarAdminException; +import org.apache.pulsar.client.admin.PulsarAdminException.NotFoundException; +import org.slf4j.Logger; +import org.slf4j.LoggerFactory; + +import java.lang.reflect.InvocationHandler; +import java.lang.reflect.InvocationTargetException; +import java.lang.reflect.Method; +import java.lang.reflect.Proxy; +import java.util.Map; +import java.util.Optional; +import java.util.concurrent.ConcurrentHashMap; + +import static java.util.concurrent.TimeUnit.MILLISECONDS; +import static org.apache.flink.connector.pulsar.common.config.PulsarOptions.PULSAR_ADMIN_REQUEST_RATES; +import static org.apache.flink.connector.pulsar.common.config.PulsarOptions.PULSAR_ADMIN_REQUEST_RETRIES; +import static org.apache.flink.connector.pulsar.common.config.PulsarOptions.PULSAR_ADMIN_REQUEST_WAIT_MILLIS; +import static org.apache.flink.shaded.guava30.com.google.common.util.concurrent.Uninterruptibles.sleepUninterruptibly; +import static org.apache.flink.util.ExceptionUtils.findThrowable; + +/** A wrapper which wraps the {@link PulsarAdmin} with request retry and rate limit support. */ +public class PulsarAdminInvocationHandler implements InvocationHandler { + private static final Logger LOG = LoggerFactory.getLogger(PulsarAdminInvocationHandler.class); + + @SuppressWarnings("java:S3077") + private static volatile RateLimiter rateLimiter; + + private final PulsarAdmin admin; + private final int retryTimes; + private final long waitMillis; + private final int requestRates; + private final Map<String, Object> handlers; + + public PulsarAdminInvocationHandler(PulsarAdmin admin, PulsarConfiguration configuration) { + this.admin = admin; + this.retryTimes = configuration.get(PULSAR_ADMIN_REQUEST_RETRIES); + this.waitMillis = configuration.get(PULSAR_ADMIN_REQUEST_WAIT_MILLIS); + this.requestRates = configuration.get(PULSAR_ADMIN_REQUEST_RATES); + this.handlers = new ConcurrentHashMap<>(); + } + + @Override + public Object invoke(Object proxy, Method method, Object[] args) throws Throwable { + Class<?> returnType = method.getReturnType(); + + // No need to proxy the void return type. + // The non-interface type is not able to proxy. + if (returnType.equals(Void.TYPE) || !returnType.isInterface()) { + return method.invoke(admin, args); + } + + String methodName = method.getName(); + if (handlers.containsKey(methodName)) { + return handlers.get(methodName); + } + + Object handler = + Proxy.newProxyInstance( + Thread.currentThread().getContextClassLoader(), + new Class[] {returnType}, + new RequestHandler(method.invoke(admin, args))); + this.handlers.put(methodName, handler); + + return handler; + } + + /** A proxy handler with retry support for all the admin request. */ + @SuppressWarnings({"java:S1193", "java:S1181", "java:S3776", "java:S112"}) + private class RequestHandler implements InvocationHandler { + + private final Object handler; + + public RequestHandler(Object handler) { + this.handler = handler; + } + + @Override + public Object invoke(Object proxy, Method method, Object[] args) throws Throwable { + return doInvoke(method, args, retryTimes); + } + + private Object doInvoke(Method method, Object[] args, int remainingTimes) throws Throwable { + while (true) { + // Make sure the request is allowed in the given rates. + requestRateLimit(requestRates); + + try { + return method.invoke(handler, args); + } catch (InvocationTargetException e) { + Optional<PulsarAdminException> optional = + findThrowable(e, PulsarAdminException.class); + if (optional.isPresent()) { + PulsarAdminException ex = optional.get(); + if (ex instanceof NotFoundException) { + // No need to retry on such exceptions. + throw ex; + } + + remainingTimes--; + LOG.warn("Request error in Admin API, remain times: {}", remainingTimes, e); + if (remainingTimes == 0) { + throw ex; + } else { + // Sleep for the given times before executing the next query. + sleepUninterruptibly(waitMillis, MILLISECONDS); + } + } else { + throw e.getCause(); + } + } + } + } + } + + /** Request a global ratelimit which limits the total admin API request rates. */ + private static void requestRateLimit(int requestRates) { + if (rateLimiter == null) { Review Comment: Maybe initiate the `rateLimit` in a hungry style is enough. This can avoid the overhead of accessing volatile variable. -- 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: issues-unsubscr...@flink.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org
