Ribbon客户端负载均衡策略测试及其改进
import java.nio.charset.StandardCharsets;
import java.util.ArrayList;
import java.util.List;
import java.util.concurrent.Callable;
import java.util.concurrent.CopyOnWriteArrayList;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.Future;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.TimeoutException;
import java.util.stream.Collectors;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.http.MediaType;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.reactive.function.client.WebClient;
import com.itmuch.cloud.study.user.entity.User;
import io.swagger.annotations.Api;
import io.swagger.annotations.ApiOperation;
import lombok.extern.slf4j.Slf4j;
import reactor.core.publisher.Mono;
@Slf4j
@Api(tags = "负载均衡节点")
@RestController
@RequestMapping("/node")
public class NodeController
{
@Autowired
private WebClient webClient;
@Value("${microservice-ribbon-user.ribbon.listOfServers}")
private List<String> listOfServers;
private ExecutorService executorService = Executors.newFixedThreadPool(10);
@ApiOperation("查询用户")
@GetMapping("/user/{id}")
public List<User> findById(@PathVariable Long id)
throws InterruptedException
{
// WebClient支持异步
List<User> users = new CopyOnWriteArrayList<User>();
listOfServers.stream()
.forEach(hostWithPort -> webClient.get()
.uri(String.format("http://%s/%s", hostWithPort, id))// URI
.acceptCharset(StandardCharsets.UTF_8)
.accept(MediaType.APPLICATION_JSON)
.retrieve()
.bodyToMono(User.class)
.subscribe(resp -> users.add(resp)));
int index = 0;
while (users.isEmpty() && (index++) < 100)
{
TimeUnit.MILLISECONDS.sleep(10);
log.info("index:{}, waitting......", index);
}
if (users.isEmpty())
{
throw new RuntimeException("查询超时，无返回值");
}
return users;
}
@ApiOperation("查询用户 by execute")
@GetMapping("/v0/user/{id}")
public List<User> findByExecute(@PathVariable Long id)
throws InterruptedException
{
// List<User> users = new ArrayList<User>();
// TODO ArrayList users一定概率有null值
// 原因:通过new ArrayList<>()初始化的大小是0，首次插入触发扩容，并发可能导致出现null值
List<User> users = new CopyOnWriteArrayList<User>();
listOfServers.stream()
.forEach(hostWithPort -> executorService.execute(() -> webClient.get()
.uri(String.format("http://%s/%s", hostWithPort, id))// URI
.acceptCharset(StandardCharsets.UTF_8)
.accept(MediaType.APPLICATION_JSON)
.retrieve()
.bodyToMono(User.class)
.subscribe(resp -> users.add(resp))));
int index = 0;
while (users.isEmpty() && (index++) < 100)
{
TimeUnit.MILLISECONDS.sleep(10);
log.info("index:{}, waitting......", index);
}
if (users.isEmpty())
{
throw new RuntimeException("查询超时，无返回值");
}
return users;
}
@ApiOperation("查询用户 by submit")
@GetMapping("/v1/user/{id}")
public List<User> findBySubmit(@PathVariable Long id)
throws InterruptedException
{
List<User> users = new CopyOnWriteArrayList<User>();
listOfServers.stream()
.forEach(hostWithPort -> executorService.submit(() -> webClient.get()
.uri(String.format("http://%s/%s", hostWithPort, id))// URI
.acceptCharset(StandardCharsets.UTF_8)
.accept(MediaType.APPLICATION_JSON)
.retrieve()
.bodyToMono(User.class)
.subscribe(resp -> users.add(resp)), users));
int index = 0;
while (users.isEmpty() && (index++) < 100)
{
TimeUnit.MILLISECONDS.sleep(10);
log.info("index:{}, waitting......", index);
}
if (users.isEmpty())
{
throw new RuntimeException("查询超时，无返回值");
}
return users;
}
@ApiOperation("查询用户 by invokeAny")
@GetMapping("/v2/user/{id}")
public User findByInvokeAny(@PathVariable Long id)
throws InterruptedException, ExecutionException, TimeoutException
{
return executorService.invokeAny(listOfServers.stream().map(hostWithPort -> new Callable<User>()
{
@Override
public User call()
{
Mono<User> mono = webClient.get()
.uri(String.format("http://%s/%s", hostWithPort, id))// URI
.acceptCharset(StandardCharsets.UTF_8)
.accept(MediaType.APPLICATION_JSON)
.retrieve()
.bodyToMono(User.class);
return mono.block();
}
}).collect(Collectors.toList()), 1000, TimeUnit.MILLISECONDS);
}
@ApiOperation("查询用户 by invokeAll")
@GetMapping("/v3/user/{id}")
public List<User> findByInvokeAll(@PathVariable Long id)
throws InterruptedException
{
List<Future<User>> futures = executorService.invokeAll(listOfServers.stream().map(hostWithPort -> new Callable<User>()
{
@Override
public User call()
{
Mono<User> mono = webClient.get()
.uri(String.format("http://%s/%s", hostWithPort, id))// URI
.acceptCharset(StandardCharsets.UTF_8)
.accept(MediaType.APPLICATION_JSON)
.retrieve()
.bodyToMono(User.class);
return mono.block();
}
}).collect(Collectors.toList()), 1000, TimeUnit.MILLISECONDS);
List<User> users = new ArrayList<User>();
for (Future<User> future : futures)
{
try
{
users.add(future.get());
}
catch (Exception e)
{
log.error(e.getMessage(), e);
}
}
return users;
}
}