Commit
This commit does not belong to any branch on this repository, and may belong to a fork outside of the repository.
Use DgraphClientPool to manage GRPC clients.
Instead of passing a list of DGraphBlockingStub clients directly to DgraphClient, we now use a DgraphClientPool to manage these clients. This allows us to better manage the lifecycle of the clients, including the ability to close or shutdown the client cleanly.
- Loading branch information
1 parent
8755cc4
commit ab161db
Showing
6 changed files
with
179 additions
and
52 deletions.
There are no files selected for viewing
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| Original file line number | Diff line number | Diff line change |
|---|---|---|
| @@ -0,0 +1,156 @@ | ||
| /* | ||
| * Copyright 2016-18 DGraph Labs, Inc. | ||
| * | ||
| * Licensed 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 io.dgraph; | ||
|
|
||
| import io.grpc.ManagedChannel; | ||
| import io.grpc.ManagedChannelBuilder; | ||
| import java.util.ArrayList; | ||
| import java.util.List; | ||
| import java.util.Random; | ||
| import java.util.concurrent.TimeUnit; | ||
| import javafx.util.Pair; | ||
|
|
||
| /** | ||
| * Manage a pool of Dgraph clients. | ||
| * | ||
| * <p>Clients must belong to the same Dgraph cluster | ||
| * | ||
| * @author Deepak Jois | ||
| */ | ||
| public class DgraphClientPool { | ||
| List<Pair<ManagedChannel, DgraphGrpc.DgraphBlockingStub>> clients; | ||
|
|
||
| private int deadlineSecs; | ||
|
|
||
| private DgraphClientPool() { | ||
| this.clients = new ArrayList<>(); | ||
| } | ||
|
|
||
| /** | ||
| * Create a pool of clients from a list of {@link ManagedChannel} objects. | ||
| * | ||
| * @param channels List of {@link ManagedChannel} objects to use when creating GRPC clients | ||
| */ | ||
| public DgraphClientPool(List<ManagedChannel> channels) { | ||
| this(); | ||
| add(channels); | ||
| } | ||
|
|
||
| /** | ||
| * Create a pool of clients from a list of {@link ManagedChannel} objects, and specify a deadline | ||
| * (in seconds) for the requests to execute. | ||
| * | ||
| * @param channels List of {@link ManagedChannel} objects to use when creating GRPC clients | ||
| * @param deadlineSecs deadline in seconds for requests made to the clients. | ||
| */ | ||
| public DgraphClientPool(List<ManagedChannel> channels, int deadlineSecs) { | ||
| this(channels); | ||
| this.deadlineSecs = deadlineSecs; | ||
| } | ||
|
|
||
| /** | ||
| * Add a client that connects to a Dgraph server located at specified host and port. | ||
| * | ||
| * @param host | ||
| * @param port | ||
| */ | ||
| public void add(String host, int port) { | ||
| ManagedChannel channel = | ||
| ManagedChannelBuilder.forAddress(host, port).usePlaintext(true).build(); | ||
| DgraphGrpc.DgraphBlockingStub stub = DgraphGrpc.newBlockingStub(channel); | ||
| clients.add(new Pair<>(channel, stub)); | ||
| } | ||
|
|
||
| /** | ||
| * Add a client that connects to a Dgraph server, using the specified {@link ManagedChannel}. | ||
| * | ||
| * @param channel | ||
| */ | ||
| public void add(ManagedChannel channel) { | ||
| DgraphGrpc.DgraphBlockingStub stub = DgraphGrpc.newBlockingStub(channel); | ||
| clients.add(new Pair<>(channel, stub)); | ||
| } | ||
|
|
||
| /** | ||
| * Add clients that connect to different nodes in a Dgraph cluster, using the specified {@link | ||
| * ManagedChannel} objects. | ||
| * | ||
| * @param channels | ||
| */ | ||
| public void add(List<ManagedChannel> channels) { | ||
| for (ManagedChannel channel : channels) { | ||
| DgraphGrpc.DgraphBlockingStub stub = DgraphGrpc.newBlockingStub(channel); | ||
| clients.add(new Pair<>(channel, stub)); | ||
| } | ||
| } | ||
|
|
||
| /** | ||
| * Returns a randomly chosen client from the pool. | ||
| * | ||
| * @return A {@link io.dgraph.DgraphGrpc.DgraphBlockingStub} object. | ||
| */ | ||
| public DgraphGrpc.DgraphBlockingStub anyClient() { | ||
| Random rand = new Random(); | ||
|
|
||
| DgraphGrpc.DgraphBlockingStub client = clients.get(rand.nextInt(clients.size())).getValue(); | ||
|
|
||
| if (deadlineSecs > 0) { | ||
| return client.withDeadlineAfter(deadlineSecs, TimeUnit.SECONDS); | ||
| } | ||
|
|
||
| return client; | ||
| } | ||
|
|
||
| /** | ||
| * Return the deadline(in secs) for the clients in the pool. | ||
| * | ||
| * @return | ||
| */ | ||
| public int getDeadline() { | ||
| return deadlineSecs; | ||
| } | ||
|
|
||
| /** | ||
| * Set the deadline for the clients in the pool in secs. | ||
| * | ||
| * @param deadlineSecs | ||
| */ | ||
| public void setDeadline(int deadlineSecs) { | ||
| this.deadlineSecs = deadlineSecs; | ||
| } | ||
|
|
||
| /** | ||
| * Closes all the clients in the pool with the specified timeout. | ||
| * | ||
| * @param timeoutSecs timeout value in seconds | ||
| * @throws InterruptedException | ||
| */ | ||
| public void close(long timeoutSecs) throws InterruptedException { | ||
| for (Pair<ManagedChannel, DgraphGrpc.DgraphBlockingStub> client : clients) { | ||
| client.getKey().awaitTermination(timeoutSecs, TimeUnit.SECONDS); | ||
| } | ||
| } | ||
|
|
||
| /** | ||
| * Closes all the clients in the pool with a default timeout of 5 seconds. | ||
| * | ||
| * @throws InterruptedException | ||
| */ | ||
| public void close() throws InterruptedException { | ||
| close(5); | ||
| } | ||
| } |
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters