Kun Zhang | 7cb0497 | 2017-01-09 14:44:10 -0800 | [diff] [blame] | 1 | /* |
| 2 | * Copyright 2016, Google Inc. All rights reserved. |
| 3 | * |
| 4 | * Redistribution and use in source and binary forms, with or without |
| 5 | * modification, are permitted provided that the following conditions are |
| 6 | * met: |
| 7 | * |
| 8 | * * Redistributions of source code must retain the above copyright |
| 9 | * notice, this list of conditions and the following disclaimer. |
| 10 | * * Redistributions in binary form must reproduce the above |
| 11 | * copyright notice, this list of conditions and the following disclaimer |
| 12 | * in the documentation and/or other materials provided with the |
| 13 | * distribution. |
| 14 | * |
| 15 | * * Neither the name of Google Inc. nor the names of its |
| 16 | * contributors may be used to endorse or promote products derived from |
| 17 | * this software without specific prior written permission. |
| 18 | * |
| 19 | * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
| 20 | * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
| 21 | * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR |
| 22 | * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT |
| 23 | * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
| 24 | * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT |
| 25 | * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
| 26 | * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
| 27 | * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| 28 | * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE |
| 29 | * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| 30 | */ |
| 31 | |
| 32 | package io.grpc.internal; |
| 33 | |
| 34 | import static com.google.common.base.Preconditions.checkNotNull; |
| 35 | import static io.grpc.ConnectivityState.READY; |
| 36 | import static io.grpc.ConnectivityState.TRANSIENT_FAILURE; |
| 37 | |
| 38 | import com.google.common.base.Stopwatch; |
| 39 | import com.google.common.base.Supplier; |
| 40 | import com.google.instrumentation.stats.StatsContextFactory; |
| 41 | |
| 42 | import io.grpc.Attributes; |
| 43 | import io.grpc.CallOptions; |
| 44 | import io.grpc.ClientCall; |
| 45 | import io.grpc.ConnectivityStateInfo; |
| 46 | import io.grpc.EquivalentAddressGroup; |
| 47 | import io.grpc.LoadBalancer2.PickResult; |
| 48 | import io.grpc.LoadBalancer2.SubchannelPicker; |
| 49 | import io.grpc.ManagedChannel; |
| 50 | import io.grpc.Metadata; |
| 51 | import io.grpc.MethodDescriptor; |
| 52 | import io.grpc.Status; |
| 53 | import io.grpc.internal.ClientCallImpl.ClientTransportProvider; |
| 54 | |
| 55 | import java.util.concurrent.CountDownLatch; |
| 56 | import java.util.concurrent.Executor; |
| 57 | import java.util.concurrent.ScheduledExecutorService; |
| 58 | import java.util.concurrent.TimeUnit; |
| 59 | import java.util.logging.Level; |
| 60 | import java.util.logging.Logger; |
| 61 | import javax.annotation.concurrent.ThreadSafe; |
| 62 | |
| 63 | /** |
| 64 | * A ManagedChannel backed by a single {@link InternalSubchannel} and used for {@link LoadBalancer2} |
| 65 | * to its own RPC needs. |
| 66 | */ |
| 67 | @ThreadSafe |
| 68 | final class OobChannel extends ManagedChannel implements WithLogId { |
| 69 | private static final Logger log = Logger.getLogger(OobChannel.class.getName()); |
| 70 | |
| 71 | private SubchannelImpl subchannelImpl; |
| 72 | private SubchannelPicker subchannelPicker; |
| 73 | |
| 74 | private final LogId logId = LogId.allocate(getClass().getName()); |
| 75 | private final StatsContextFactory statsFactory; |
| 76 | private final String authority; |
| 77 | private final DelayedClientTransport2 delayedTransport; |
| 78 | private final ObjectPool<? extends Executor> executorPool; |
| 79 | private final Executor executor; |
| 80 | private final ScheduledExecutorService deadlineCancellationExecutor; |
| 81 | private final Supplier<Stopwatch> stopwatchSupplier; |
| 82 | private final CountDownLatch terminatedLatch = new CountDownLatch(1); |
| 83 | private volatile boolean shutdown; |
| 84 | |
| 85 | private final ClientTransportProvider transportProvider = new ClientTransportProvider() { |
| 86 | @Override |
| 87 | public ClientTransport get(CallOptions callOptions, Metadata headers) { |
| 88 | // delayed transport's newStream() always acquires a lock, but concurrent performance doesn't |
| 89 | // matter here because OOB communication should be sparse, and it's not on application RPC's |
| 90 | // critical path. |
| 91 | return delayedTransport; |
| 92 | } |
| 93 | }; |
| 94 | |
| 95 | OobChannel(StatsContextFactory statsFactory, String authority, |
| 96 | ObjectPool<? extends Executor> executorPool, |
| 97 | ScheduledExecutorService deadlineCancellationExecutor, Supplier<Stopwatch> stopwatchSupplier, |
| 98 | ChannelExecutor channelExecutor) { |
| 99 | this.statsFactory = checkNotNull(statsFactory, "statsFactory"); |
| 100 | this.authority = checkNotNull(authority, "authority"); |
| 101 | this.executorPool = checkNotNull(executorPool, "executorPool"); |
| 102 | this.executor = checkNotNull(executorPool.getObject(), "executor"); |
| 103 | this.deadlineCancellationExecutor = checkNotNull( |
| 104 | deadlineCancellationExecutor, "deadlineCancellationExecutor"); |
| 105 | this.stopwatchSupplier = checkNotNull(stopwatchSupplier, "stopwatchSupplier"); |
| 106 | this.delayedTransport = new DelayedClientTransport2(executor, channelExecutor); |
| 107 | this.delayedTransport.start(new ManagedClientTransport.Listener() { |
| 108 | @Override |
| 109 | public void transportShutdown(Status s) { |
| 110 | // Don't care |
| 111 | } |
| 112 | |
| 113 | @Override |
| 114 | public void transportTerminated() { |
| 115 | subchannelImpl.shutdown(); |
| 116 | } |
| 117 | |
| 118 | @Override |
| 119 | public void transportReady() { |
| 120 | // Don't care |
| 121 | } |
| 122 | |
| 123 | @Override |
| 124 | public void transportInUse(boolean inUse) { |
| 125 | // Don't care |
| 126 | } |
| 127 | }); |
| 128 | } |
| 129 | |
| 130 | // Must be called only once, right after the OobChannel is created. |
| 131 | void setSubchannel(final InternalSubchannel subchannel) { |
| 132 | log.log(Level.FINE, "[{0}] Created with [{1}]", new Object[] {this, subchannel}); |
| 133 | subchannelImpl = new SubchannelImpl() { |
| 134 | @Override |
| 135 | public void shutdown() { |
| 136 | subchannel.shutdown(); |
| 137 | } |
| 138 | |
| 139 | @Override |
| 140 | ClientTransport obtainActiveTransport() { |
| 141 | return subchannel.obtainActiveTransport(); |
| 142 | } |
| 143 | |
| 144 | @Override |
| 145 | public void requestConnection() { |
| 146 | subchannel.obtainActiveTransport(); |
| 147 | } |
| 148 | |
| 149 | @Override |
| 150 | public EquivalentAddressGroup getAddresses() { |
| 151 | return subchannel.getAddressGroup(); |
| 152 | } |
| 153 | |
| 154 | @Override |
| 155 | public Attributes getAttributes() { |
| 156 | return Attributes.EMPTY; |
| 157 | } |
| 158 | }; |
| 159 | |
| 160 | subchannelPicker = new SubchannelPicker() { |
| 161 | final PickResult result = PickResult.withSubchannel(subchannelImpl); |
| 162 | |
| 163 | @Override |
| 164 | public PickResult pickSubchannel(Attributes affinity, Metadata headers) { |
| 165 | return result; |
| 166 | } |
| 167 | }; |
| 168 | delayedTransport.reprocess(subchannelPicker); |
| 169 | } |
| 170 | |
| 171 | @Override |
| 172 | public <RequestT, ResponseT> ClientCall<RequestT, ResponseT> newCall( |
| 173 | MethodDescriptor<RequestT, ResponseT> methodDescriptor, CallOptions callOptions) { |
| 174 | StatsTraceContext statsTraceCtx = StatsTraceContext.newClientContext( |
| 175 | methodDescriptor.getFullMethodName(), statsFactory, stopwatchSupplier); |
| 176 | return new ClientCallImpl<RequestT, ResponseT>(methodDescriptor, |
| 177 | callOptions.getExecutor() == null ? executor : callOptions.getExecutor(), |
| 178 | callOptions, statsTraceCtx, transportProvider, |
| 179 | deadlineCancellationExecutor); |
| 180 | } |
| 181 | |
| 182 | @Override |
| 183 | public String authority() { |
| 184 | return authority; |
| 185 | } |
| 186 | |
| 187 | @Override |
| 188 | public LogId getLogId() { |
| 189 | return logId; |
| 190 | } |
| 191 | |
| 192 | @Override |
| 193 | public boolean isTerminated() { |
| 194 | return terminatedLatch.getCount() == 0; |
| 195 | } |
| 196 | |
| 197 | @Override |
| 198 | public boolean awaitTermination(long time, TimeUnit unit) throws InterruptedException { |
| 199 | return terminatedLatch.await(time, unit); |
| 200 | } |
| 201 | |
| 202 | @Override |
| 203 | public ManagedChannel shutdown() { |
| 204 | shutdown = true; |
| 205 | delayedTransport.shutdown(); |
| 206 | return this; |
| 207 | } |
| 208 | |
| 209 | @Override |
| 210 | public boolean isShutdown() { |
| 211 | return shutdown; |
| 212 | } |
| 213 | |
| 214 | @Override |
| 215 | public ManagedChannel shutdownNow() { |
| 216 | shutdown = true; |
| 217 | delayedTransport.shutdownNow( |
| 218 | Status.UNAVAILABLE.withDescription("OobChannel.shutdownNow() called")); |
| 219 | return this; |
| 220 | } |
| 221 | |
| 222 | void handleSubchannelStateChange(final ConnectivityStateInfo newState) { |
| 223 | switch (newState.getState()) { |
| 224 | case READY: |
| 225 | case IDLE: |
| 226 | delayedTransport.reprocess(subchannelPicker); |
| 227 | break; |
| 228 | case TRANSIENT_FAILURE: |
| 229 | delayedTransport.reprocess(new SubchannelPicker() { |
| 230 | final PickResult errorResult = PickResult.withError(newState.getStatus()); |
| 231 | |
| 232 | @Override |
| 233 | public PickResult pickSubchannel(Attributes affinity, Metadata headers) { |
| 234 | return errorResult; |
| 235 | } |
| 236 | }); |
| 237 | break; |
| 238 | default: |
| 239 | // Do nothing |
| 240 | } |
| 241 | } |
| 242 | |
| 243 | void handleSubchannelTerminated() { |
| 244 | // When delayedTransport is terminated, it shuts down subchannel. Therefore, at this point |
| 245 | // both delayedTransport and subchannel have terminated. |
| 246 | executorPool.returnObject(executor); |
| 247 | terminatedLatch.countDown(); |
| 248 | } |
| 249 | } |