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/** * 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 com.twitter.distributedlog.service.config; import com.google.common.base.Preconditions; import com.twitter.distributedlog.DLSN; import com.twitter.distributedlog.DistributedLogConfiguration; import com.twitter.distributedlog.DistributedLogConstants; import com.twitter.distributedlog.service.streamset.IdentityStreamPartitionConverter; import com.twitter.distributedlog.service.streamset.StreamPartitionConverter; import org.apache.bookkeeper.util.ReflectionUtils; import org.apache.commons.configuration.CompositeConfiguration; import org.apache.commons.configuration.ConfigurationException; import org.apache.commons.configuration.SystemConfiguration; /** * Configuration for DistributedLog Server */ public class ServerConfiguration extends CompositeConfiguration { private static ClassLoader defaultLoader; static { defaultLoader = Thread.currentThread().getContextClassLoader(); if (null == defaultLoader) { defaultLoader = DistributedLogConfiguration.class.getClassLoader(); } } // Server DLSN version protected final static String SERVER_DLSN_VERSION = "server_dlsn_version"; protected final static byte SERVER_DLSN_VERSION_DEFAULT = DLSN.VERSION1; // Server Durable Write Enable/Disable Flag protected final static String SERVER_DURABLE_WRITE_ENABLED = "server_durable_write_enabled"; protected final static boolean SERVER_DURABLE_WRITE_ENABLED_DEFAULT = true; // Server Region Id protected final static String SERVER_REGION_ID = "server_region_id"; protected final static int SERVER_REGION_ID_DEFAULT = DistributedLogConstants.LOCAL_REGION_ID; // Server Port protected final static String SERVER_PORT = "server_port"; protected final static int SERVER_PORT_DEFAULT = 0; // Server Shard Id protected final static String SERVER_SHARD_ID = "server_shard"; protected final static int SERVER_SHARD_ID_DEFAULT = -1; // Server Threads protected final static String SERVER_NUM_THREADS = "server_threads"; protected final static int SERVER_NUM_THREADS_DEFAULT = Runtime.getRuntime().availableProcessors(); // Server enable per stream stat protected final static String SERVER_ENABLE_PERSTREAM_STAT = "server_enable_perstream_stat"; protected final static boolean SERVER_ENABLE_PERSTREAM_STAT_DEFAULT = true; // Server graceful shutdown period (in millis) protected final static String SERVER_GRACEFUL_SHUTDOWN_PERIOD_MS = "server_graceful_shutdown_period_ms"; protected final static long SERVER_GRACEFUL_SHUTDOWN_PERIOD_MS_DEFAULT = 0L; // Server service timeout public static final String SERVER_SERVICE_TIMEOUT_MS = "server_service_timeout_ms"; public static final String SERVER_SERVICE_TIMEOUT_MS_OLD = "serviceTimeoutMs"; public static final long SERVER_SERVICE_TIMEOUT_MS_DEFAULT = 0; // Server stream probation timeout public static final String SERVER_STREAM_PROBATION_TIMEOUT_MS = "server_stream_probation_timeout_ms"; public static final String SERVER_STREAM_PROBATION_TIMEOUT_MS_OLD = "streamProbationTimeoutMs"; public static final long SERVER_STREAM_PROBATION_TIMEOUT_MS_DEFAULT = 60 * 1000 * 5; // Server stream to partition converter protected final static String SERVER_STREAM_PARTITION_CONVERTER_CLASS = "stream_partition_converter_class"; public ServerConfiguration() { super(); addConfiguration(new SystemConfiguration()); } /** * Load configurations from {@link DistributedLogConfiguration} * * @param dlConf * distributedlog configuration */ public void loadConf(DistributedLogConfiguration dlConf) { addConfiguration(dlConf); } /** * Set the version to encode dlsn. * * @param version * dlsn version * @return server configuration */ public ServerConfiguration setDlsnVersion(byte version) { setProperty(SERVER_DLSN_VERSION, version); return this; } /** * Get the version to encode dlsn. * * @see DLSN * @return version to encode dlsn. */ public byte getDlsnVersion() { return getByte(SERVER_DLSN_VERSION, SERVER_DLSN_VERSION_DEFAULT); } /** * Set the flag to enable/disable durable write * * @param enabled * flag to enable/disable durable write * @return server configuration */ public ServerConfiguration enableDurableWrite(boolean enabled) { setProperty(SERVER_DURABLE_WRITE_ENABLED, enabled); return this; } /** * Is durable write enabled? * * @return true if waiting writes to be durable. otherwise false. */ public boolean isDurableWriteEnabled() { return getBoolean(SERVER_DURABLE_WRITE_ENABLED, SERVER_DURABLE_WRITE_ENABLED_DEFAULT); } /** * Set the region id used to instantiate DistributedLogNamespace * * @param regionId * region id * @return server configuration */ public ServerConfiguration setRegionId(int regionId) { setProperty(SERVER_REGION_ID, regionId); return this; } /** * Get the region id used to instantiate * {@link com.twitter.distributedlog.namespace.DistributedLogNamespace} * * @return region id used to instantiate DistributedLogNamespace */ public int getRegionId() { return getInt(SERVER_REGION_ID, SERVER_REGION_ID_DEFAULT); } /** * Set the server port running for this service. * * @param port * server port * @return server configuration */ public ServerConfiguration setServerPort(int port) { setProperty(SERVER_PORT, port); return this; } /** * Get the server port running for this service. * * @return server port */ public int getServerPort() { return getInt(SERVER_PORT, SERVER_PORT_DEFAULT); } /** * Set the shard id of this server. * * @param shardId * shard id * @return shard id of this server */ public ServerConfiguration setServerShardId(int shardId) { setProperty(SERVER_SHARD_ID, shardId); return this; } /** * Get the shard id of this server. It would be used to instantiate the client id * used for DistributedLogNamespace. * * @return shard id of this server. */ public int getServerShardId() { return getInt(SERVER_SHARD_ID, SERVER_SHARD_ID_DEFAULT); } /** * Get the number of threads for the executor of this server. * * @return number of threads for the executor running in this server. */ public int getServerThreads() { return getInt(SERVER_NUM_THREADS, SERVER_NUM_THREADS_DEFAULT); } /** * Set the number of threads for the executor of this server. * * @param numThreads * number of threads for the executor running in this server. * @return server configuration */ public ServerConfiguration setServerThreads(int numThreads) { setProperty(SERVER_NUM_THREADS, numThreads); return this; } /** * Enable/Disable per stream stat. * * @param enabled * flag to enable/disable per stream stat * @return server configuration */ public ServerConfiguration setPerStreamStatEnabled(boolean enabled) { setProperty(SERVER_ENABLE_PERSTREAM_STAT, enabled); return this; } /** * Whether the per stream stat enabled for not in this server. * * @return true if per stream stat enable, otherwise false. */ public boolean isPerStreamStatEnabled() { return getBoolean(SERVER_ENABLE_PERSTREAM_STAT, SERVER_ENABLE_PERSTREAM_STAT_DEFAULT); } /** * Set the graceful shutdown period in millis. * * @param periodMs * graceful shutdown period in millis. * @return server configuration */ public ServerConfiguration setGracefulShutdownPeriodMs(long periodMs) { setProperty(SERVER_GRACEFUL_SHUTDOWN_PERIOD_MS, periodMs); return this; } /** * Get the graceful shutdown period in millis. * * @return graceful shutdown period in millis. */ public long getGracefulShutdownPeriodMs() { return getLong(SERVER_GRACEFUL_SHUTDOWN_PERIOD_MS, SERVER_GRACEFUL_SHUTDOWN_PERIOD_MS_DEFAULT); } /** * Get timeout for stream op execution in proxy layer. 0 disables timeout. * * @return timeout for stream operation in proxy layer. */ public long getServiceTimeoutMs() { return getLong(SERVER_SERVICE_TIMEOUT_MS, getLong(SERVER_SERVICE_TIMEOUT_MS_OLD, SERVER_SERVICE_TIMEOUT_MS_DEFAULT)); } /** * Set timeout for stream op execution in proxy layer. 0 disables timeout. * * @param timeoutMs * timeout for stream operation in proxy layer. * @return dl configuration. */ public ServerConfiguration setServiceTimeoutMs(long timeoutMs) { setProperty(SERVER_SERVICE_TIMEOUT_MS, timeoutMs); return this; } /** * After service timeout, how long should stream be kept in cache in probationary state in order * to prevent reacquire. In millisec. * * @return stream probation timeout in ms. */ public long getStreamProbationTimeoutMs() { return getLong(SERVER_STREAM_PROBATION_TIMEOUT_MS, getLong(SERVER_STREAM_PROBATION_TIMEOUT_MS_OLD, SERVER_STREAM_PROBATION_TIMEOUT_MS_DEFAULT)); } /** * After service timeout, how long should stream be kept in cache in probationary state in order * to prevent reacquire. In millisec. * * @param timeoutMs probation timeout in ms. */ public ServerConfiguration setStreamProbationTimeoutMs(long timeoutMs) { setProperty(SERVER_STREAM_PROBATION_TIMEOUT_MS, timeoutMs); return this; } /** * Set the stream partition converter class. * * @param converterClass * stream partition converter class * @return server configuration */ public ServerConfiguration setStreamPartitionConverterClass( Class<? extends StreamPartitionConverter> converterClass) { setProperty(SERVER_STREAM_PARTITION_CONVERTER_CLASS, converterClass.getName()); return this; } /** * Get the stream partition converter class. * * @return the stream partition converter class. * @throws ConfigurationException */ public Class<? extends StreamPartitionConverter> getStreamPartitionConverterClass() throws ConfigurationException { return ReflectionUtils.getClass(this, SERVER_STREAM_PARTITION_CONVERTER_CLASS, IdentityStreamPartitionConverter.class, StreamPartitionConverter.class, defaultLoader); } /** * Validate the configuration */ public void validate() { byte dlsnVersion = getDlsnVersion(); Preconditions.checkArgument(dlsnVersion >= DLSN.VERSION0 && dlsnVersion <= DLSN.VERSION1, "Unknown dlsn version " + dlsnVersion); Preconditions.checkArgument(getServerThreads() > 0, "Invalid number of server threads : " + getServerThreads()); Preconditions.checkArgument(getServerShardId() >= 0, "Invalid server shard id : " + getServerShardId()); } }