jersey-clientでリクエスト/レスポンスのログを出す

やりたいこと

リクエスト/レスポンスのbodyをログに出したい。

依存関係

    <dependencies>
        <dependency>
            <groupId>org.glassfish.jersey.core</groupId>
            <artifactId>jersey-client</artifactId>
            <version>2.35</version>
        </dependency>
        <dependency>
            <groupId>org.glassfish.jersey.media</groupId>
            <artifactId>jersey-media-json-jackson</artifactId>
            <version>2.35</version>
        </dependency>
        <dependency>
            <groupId>org.glassfish.jersey.inject</groupId>
            <artifactId>jersey-hk2</artifactId>
            <version>2.35</version>
        </dependency>
        <dependency>
            <groupId>org.slf4j</groupId>
            <artifactId>slf4j-api</artifactId>
            <version>1.7.32</version>
        </dependency>
        <dependency>
            <groupId>ch.qos.logback</groupId>
            <artifactId>logback-classic</artifactId>
            <version>1.2.7</version>
        </dependency>
        <dependency>
            <groupId>ch.qos.logback</groupId>
            <artifactId>logback-core</artifactId>
            <version>1.2.7</version>
        </dependency>
    </dependencies>

フィルタの実装

リクエストはノーチェックでjsonとしてパースしているので、実際に使用する場合はclientRequestContext.getMediaType()でタイプチェックしたほうがよい。

package jp.co.neosystem.wg;

import com.fasterxml.jackson.databind.ObjectMapper;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import javax.ws.rs.client.ClientRequestContext;
import javax.ws.rs.client.ClientRequestFilter;
import javax.ws.rs.client.ClientResponseContext;
import javax.ws.rs.client.ClientResponseFilter;
import java.io.*;

public class LoggingFilter implements ClientRequestFilter, ClientResponseFilter  {

    private static final Logger LOGGER = LoggerFactory.getLogger(LoggingFilter.class);

    @Override
    public void filter(ClientRequestContext clientRequestContext) throws IOException {
        if (!clientRequestContext.hasEntity()) {
            return;
        }

        Object entity = clientRequestContext.getEntity();

        ObjectMapper mapper = new ObjectMapper();
        String entityString = mapper.writeValueAsString(entity);

        LOGGER.info(entityString);
        return;
    }

    @Override
    public void filter(ClientRequestContext clientRequestContext, ClientResponseContext clientResponseContext) throws IOException {
        if (!clientResponseContext.hasEntity()) {
            return;
        }

        ByteArrayOutputStream outputStream = new ByteArrayOutputStream();
        try (InputStream stream = clientResponseContext.getEntityStream()) {
            while (true) {
                byte[] b = new byte[1024];
                int length = stream.read(b);
                if (length <= 0) {
                    break;
                }
                outputStream.write(b, 0, length);
            }
        }
        ByteArrayInputStream inputStream = new ByteArrayInputStream(outputStream.toByteArray());
        clientResponseContext.setEntityStream(inputStream);

        LOGGER.info(outputStream.toString());
        return;
    }
}

利用法

import javax.ws.rs.client.Client;
import javax.ws.rs.client.ClientBuilder;
import javax.ws.rs.client.Entity;
import javax.ws.rs.core.Response;

// 途中省略
    private static final Client CLIENT;

    static {
        CLIENT = ClientBuilder.newClient().register(LoggingFilter.class);
    }