package com.bazaarvoice.ostrich.examples.calculator.client;
import com.bazaarvoice.ostrich.ServiceEndPoint;
import com.bazaarvoice.ostrich.ServiceFactory;
import com.bazaarvoice.ostrich.pool.ServicePoolBuilder;
import com.sun.jersey.api.client.Client;
import com.sun.jersey.api.client.ClientHandlerException;
import com.sun.jersey.api.client.UniformInterfaceException;
import com.sun.jersey.client.apache4.ApacheHttpClient4;
import com.sun.jersey.client.apache4.ApacheHttpClient4Handler;
import com.sun.jersey.client.apache4.config.ApacheHttpClient4Config;
import com.sun.jersey.client.apache4.config.DefaultApacheHttpClient4Config;
import com.yammer.dropwizard.client.HttpClientBuilder;
import com.yammer.dropwizard.client.HttpClientConfiguration;
import com.yammer.dropwizard.jersey.JacksonMessageBodyProvider;
import com.yammer.dropwizard.json.ObjectMapperFactory;
import com.yammer.dropwizard.validation.Validator;
import org.apache.http.client.HttpClient;
import java.net.URI;
public class CalculatorServiceFactory implements ServiceFactory<CalculatorService> {
private final Client _client;
/**
* Connects to the CalculatorService using the Apache commons http client library.
*/
public CalculatorServiceFactory(HttpClientConfiguration configuration) {
this(createDefaultJerseyClient(configuration));
}
/**
* Connects to the CalculatorService using the specified Jersey client. If you're writing a Dropwizard server,
* use @{link JerseyClientFactory} to create the Jersey client.
*/
public CalculatorServiceFactory(Client jerseyClient) {
_client = jerseyClient;
}
private static ApacheHttpClient4 createDefaultJerseyClient(HttpClientConfiguration configuration) {
HttpClient httpClient = new HttpClientBuilder().using(configuration).build();
ApacheHttpClient4Handler handler = new ApacheHttpClient4Handler(httpClient, null, true);
ApacheHttpClient4Config config = new DefaultApacheHttpClient4Config();
config.getSingletons().add(new JacksonMessageBodyProvider(new ObjectMapperFactory().build(), new Validator()));
return new ApacheHttpClient4(handler, config);
}
@Override
public String getServiceName() {
return "calculator";
}
@Override
public void configure(ServicePoolBuilder<CalculatorService> servicePoolBuilder) {
// We're fine with the default configuration, including the random load balancer, so we do nothing.
}
@Override
public CalculatorService create(ServiceEndPoint endPoint) {
return new CalculatorClient(endPoint, _client);
}
@Override
public void destroy(ServiceEndPoint endPoint, CalculatorService service) {
// We don't need to do any cleanup.
}
@Override
public boolean isRetriableException(Exception exception) {
// Try another server if network error (ClientHandlerException) or 5xx response code (UniformInterfaceException)
return exception instanceof ClientHandlerException ||
(exception instanceof UniformInterfaceException &&
((UniformInterfaceException) exception).getResponse().getStatus() >= 500);
}
@Override
public boolean isHealthy(ServiceEndPoint endPoint) {
URI adminUrl = Payload.valueOf(endPoint.getPayload()).getAdminUrl();
return _client.resource(adminUrl).path("/healthcheck").head().getStatus() == 200;
}
}