springboot 部分转发（不使用拦截器）

springboot 部分转发（不使用拦截器）

曾一峰
  2022-05-10 10:16:23 2022-05-10 10:16 创建   2023-08-11 07:07:16 2023-08-11 07:07 更新      1.8k 字  10 分钟  

前言

本篇文章实现springboot在没有接口可以访问的时候，也就是正常来说服务器应该返回404的接口转发到其他的服务器上的功能
需要有一定的springboot基础

一、Interceptor

一想到转发，首先我想到的就是拦截器了，噼里啪啦就开始操作，代码类似如下：

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
import java.nio.charset.StandardCharsets;
import java.util.Enumeration;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import com.aw.ccpos.util.HttpServletRequestReader;
import com.aw.ccpos.util.HttpUtils;
import com.aw.ccpos.util.SysUtil;
import com.aw.service.pos.base.model.RequestModel;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Component;
import org.springframework.util.StreamUtils;
import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.ModelAndView;

@Component
public class InfoInterceptor implements HandlerInterceptor {
	private static final Logger LOG = LoggerFactory.getLogger(InfoInterceptor.class);
	@Override
	public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler)
			throws Exception {
		return true;// 只有返回true才会继续向下执行，返回false取消当前请求
	}

	@Override
	public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler,
						  ModelAndView modelAndView) throws Exception {
						  
	}
}

postHandle方法中的ModelAndView 可以自定义404的错误页面，HttpServletResponse 则是返回，但是尝试过后发现所有的接口都要这么搞一遍，意思是如果通过这个办法所有的接口都会被拦截转发，这并不是我们想要的

二、/**

左思右想过后采用了如下方法

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
import com.aw.ccpos.constants.Constants;
import io.swagger.annotations.Api;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.http.MediaType;
import org.springframework.http.ResponseEntity;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RestController;


import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

@RestController
@Api(value = "GraphDB", tags = {
        "graphdb-Api"
})
public class GraphDBController {




    @Autowired
    private RoutingDelegate routingDelegate;

    @RequestMapping(value = "/**", method = {RequestMethod.GET, RequestMethod.POST, RequestMethod.PUT, RequestMethod.DELETE}, produces = MediaType.TEXT_PLAIN_VALUE)
    public ResponseEntity catchAll(HttpServletRequest request, HttpServletResponse response) {
        return routingDelegate.redirect(request, response,  Constants.SERVER_URL, null);
    }
}

既然我们只需要处理服务器找不到的方法，那么只需要/**然后包含我们页面的请求类型就好了，因为我代理转发的工具类需要MediaType.TEXT_PLAIN_VALUE类型，所以我这么设置，读者可以如不需要可以自己写转发，RoutingDelegate 转发工具类会在后文提供

1.RoutingDelegate

转发工具类 代码如下（示例）：

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
import com.aw.ccpos.util.HttpsUtils;
import org.apache.http.conn.ssl.NoopHostnameVerifier;
import org.apache.http.conn.ssl.SSLConnectionSocketFactory;
import org.apache.http.conn.ssl.TrustStrategy;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.HttpClients;
import org.springframework.http.*;
import org.springframework.http.client.HttpComponentsClientHttpRequestFactory;
import org.springframework.stereotype.Service;
import org.springframework.util.MultiValueMap;
import org.springframework.util.StreamUtils;
import org.springframework.web.client.RestTemplate;

import javax.net.ssl.*;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.io.InputStream;
import java.net.URI;
import java.net.URISyntaxException;
import java.security.KeyManagementException;
import java.security.KeyStoreException;
import java.security.NoSuchAlgorithmException;
import java.util.Collections;
import java.util.List;


import java.io.IOException;
import java.net.HttpURLConnection;
import java.security.SecureRandom;
import java.security.cert.X509Certificate;

@Service
public class RoutingDelegate {


    public ResponseEntity<String> redirect(HttpServletRequest request, HttpServletResponse response,String routeUrl, String prefix) {
        try {
            // build up the redirect URL
            String redirectUrl = createRedictUrl(request,routeUrl, prefix);
            RequestEntity requestEntity = createRequestEntity(request, redirectUrl);
            return route(requestEntity);
        } catch (Exception e) {
            return new ResponseEntity("REDIRECT ERROR", HttpStatus.INTERNAL_SERVER_ERROR);
        }
    }

    private String createRedictUrl(HttpServletRequest request, String routeUrl, String prefix) {
        String queryString = request.getQueryString();
        return routeUrl + request.getRequestURI() +
                (queryString != null ? "?" + queryString : "");
    }


    private RequestEntity createRequestEntity(HttpServletRequest request, String url) throws URISyntaxException, IOException {
        String method = request.getMethod();
        HttpMethod httpMethod = HttpMethod.resolve(method);
        MultiValueMap<String, String> headers = parseRequestHeader(request);
        byte[] body = parseRequestBody(request);
        return new RequestEntity<>(body, headers, httpMethod, new URI(url));
    }

    private ResponseEntity<String> route(RequestEntity requestEntity) {
        ResponseEntity<String> responseEntity;
        responseEntity = getRestTemplate().exchange(requestEntity, String.class);
        return responseEntity;
    }


    private byte[] parseRequestBody(HttpServletRequest request) throws IOException {
        InputStream inputStream = request.getInputStream();
        return StreamUtils.copyToByteArray(inputStream);
    }

    private MultiValueMap<String, String> parseRequestHeader(HttpServletRequest request) {
        HttpHeaders headers = new HttpHeaders();
        List<String> headerNames = Collections.list(request.getHeaderNames());
        for (String headerName : headerNames) {
            List<String> headerValues = Collections.list(request.getHeaders(headerName));
            for (String headerValue : headerValues) {
                headers.add(headerName, headerValue);
            }
        }
        return headers;
    }

    public static RestTemplate getRestTemplate()  {
        try {
            SSLContext sslContext = SSLContext.getInstance("TLS");
            KeyManager[] keyManagers = HttpsUtils.prepareKeyManager(null, null);
            TrustManager[] trustManagers = HttpsUtils.prepareTrustManager(null);
            TrustManager trustManager = null;
            if (trustManagers != null) {
                trustManager = new HttpsUtils.MyTrustManager( HttpsUtils.chooseTrustManager(trustManagers));
            } else {
                trustManager = new HttpsUtils.UnSafeTrustManager();
            }
            sslContext.init(keyManagers, new TrustManager[]{trustManager}, new SecureRandom());
            SSLConnectionSocketFactory csf = new SSLConnectionSocketFactory(sslContext,
                    new String[]{"TLSv1"},
                    null,
                    NoopHostnameVerifier.INSTANCE);

            CloseableHttpClient httpClient = HttpClients.custom()
                    .setSSLSocketFactory(csf)
                    .build();

            HttpComponentsClientHttpRequestFactory requestFactory =
                    new HttpComponentsClientHttpRequestFactory();

            requestFactory.setHttpClient(httpClient);
            RestTemplate restTemplate = new RestTemplate(requestFactory);
            return restTemplate;
        }catch (NoSuchAlgorithmException | KeyManagementException | KeyStoreException e) {
            throw new AssertionError(e);
        }
    }
}

就是一个比较标准的https的转发类，比较值得一提的是getRestTemplate()方法，它封装了一个信任任何证书的RestTemplate转发，不然https请求转发会报错，工具类HttpsUtil在下文会给出

2.HttpsUtils（https支持）

代码如下（示例）：

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
import java.io.IOException;
import java.io.InputStream;
import java.lang.reflect.Field;
import java.security.KeyManagementException;
import java.security.KeyStore;
import java.security.KeyStoreException;
import java.security.NoSuchAlgorithmException;
import java.security.SecureRandom;
import java.security.cert.CertificateException;
import java.security.cert.CertificateFactory;
import java.security.cert.X509Certificate;

import javax.net.ssl.HostnameVerifier;
import javax.net.ssl.KeyManager;
import javax.net.ssl.KeyManagerFactory;
import javax.net.ssl.SSLContext;
import javax.net.ssl.SSLSession;
import javax.net.ssl.SSLSocketFactory;
import javax.net.ssl.TrustManager;
import javax.net.ssl.TrustManagerFactory;
import javax.net.ssl.X509TrustManager;

import okhttp3.OkHttpClient;
import org.slf4j.LoggerFactory;

public class HttpsUtils {
    private static final org.slf4j.Logger Logger = LoggerFactory.getLogger(HttpsUtils.class);
    public static SSLSocketFactory getSslSocketFactory(InputStream[] certificates, InputStream bksFile, String password) {
        try {
            TrustManager[] trustManagers = prepareTrustManager(certificates);
            KeyManager[] keyManagers = prepareKeyManager(bksFile, password);
            SSLContext sslContext = SSLContext.getInstance("TLS");
            TrustManager trustManager = null;
            if (trustManagers != null) {
                trustManager = new MyTrustManager(chooseTrustManager(trustManagers));
            } else {
                trustManager = new UnSafeTrustManager();
            }
            sslContext.init(keyManagers, new TrustManager[]{trustManager}, new SecureRandom());
            return sslContext.getSocketFactory();
        } catch (NoSuchAlgorithmException e) {
            throw new AssertionError(e);
        } catch (KeyManagementException e) {
            throw new AssertionError(e);
        } catch (KeyStoreException e) {
            throw new AssertionError(e);
        }
    }

    public static TrustManager[] prepareTrustManager(InputStream... certificates) {
        if (certificates == null || certificates.length <= 0) return null;
        try {
            CertificateFactory certificateFactory = CertificateFactory.getInstance("X.509");
            KeyStore keyStore = KeyStore.getInstance(KeyStore.getDefaultType());
            keyStore.load(null);
            int index = 0;
            for (InputStream certificate : certificates) {
                String certificateAlias = Integer.toString(index++);
                keyStore.setCertificateEntry(certificateAlias, certificateFactory.generateCertificate(certificate));
                try {
                    if (certificate != null)
                        certificate.close();
                } catch (IOException e) {
                    Logger.error("error to close certificate", e);
                }
            }
            TrustManagerFactory trustManagerFactory = null;
            trustManagerFactory = TrustManagerFactory.getInstance(TrustManagerFactory.getDefaultAlgorithm());
            trustManagerFactory.init(keyStore);
            TrustManager[] trustManagers = trustManagerFactory.getTrustManagers();
            return trustManagers;
        } catch (Exception e) {
            Logger.error("fail to prepareTrustManager", e);
        }
        return null;

    }

    public static KeyManager[] prepareKeyManager(InputStream bksFile, String password) {
        try {
            if (bksFile == null || password == null) return null;
            KeyStore clientKeyStore = KeyStore.getInstance("BKS");
            clientKeyStore.load(bksFile, password.toCharArray());
            KeyManagerFactory keyManagerFactory = KeyManagerFactory.getInstance(KeyManagerFactory.getDefaultAlgorithm());
            keyManagerFactory.init(clientKeyStore, password.toCharArray());
            return keyManagerFactory.getKeyManagers();
        } catch (Exception e) {
            Logger.error("fail to prepareKeyManager", e);
        }
        return null;
    }

    public static X509TrustManager chooseTrustManager(TrustManager[] trustManagers) {
        for (TrustManager trustManager : trustManagers) {
            if (trustManager instanceof X509TrustManager) {
                return (X509TrustManager) trustManager;
            }
        }
        return null;
    }

    public static void ignoreSSLCheck(OkHttpClient sClient) {
        SSLContext sc = null;
        try {
            sc = SSLContext.getInstance("SSL");
            sc.init(null, new TrustManager[]{new X509TrustManager() {
                @Override
                public void checkClientTrusted(X509Certificate[] chain, String authType) throws CertificateException {

                }

                @Override
                public void checkServerTrusted(X509Certificate[] chain, String authType) throws CertificateException {

                }

                @Override
                public X509Certificate[] getAcceptedIssuers() {
                    return null;
                }
            }}, new SecureRandom());
        } catch (Exception e) {
            Logger.error("fail to ignoreSSLCheck", e);
        }

        HostnameVerifier hv1 = new HostnameVerifier() {
            @Override
            public boolean verify(String hostname, SSLSession session) {
                return true;
            }
        };

        String workerClassName = "okhttp3.OkHttpClient";
        try {
            Class workerClass = Class.forName(workerClassName);
            Field hostnameVerifier = workerClass.getDeclaredField("hostnameVerifier");
            hostnameVerifier.setAccessible(true);
            hostnameVerifier.set(sClient, hv1);

            Field sslSocketFactory = workerClass.getDeclaredField("sslSocketFactory");
            sslSocketFactory.setAccessible(true);
            sslSocketFactory.set(sClient, sc.getSocketFactory());
        } catch (Exception e) {
            Logger.error("fail to hostnameVerifier", e);
        }
    }

    public static class UnSafeTrustManager implements X509TrustManager {
        @Override
        public void checkClientTrusted(X509Certificate[] chain, String authType) throws CertificateException {
        }

        @Override
        public void checkServerTrusted(X509Certificate[] chain, String authType) throws CertificateException {
        }

        @Override
        public X509Certificate[] getAcceptedIssuers() {
            return new X509Certificate[]{};
        }
    }

    public static class MyTrustManager implements X509TrustManager {
        private X509TrustManager defaultTrustManager;
        private X509TrustManager localTrustManager;

        public MyTrustManager(X509TrustManager localTrustManager) throws NoSuchAlgorithmException, KeyStoreException {
            TrustManagerFactory var4 = TrustManagerFactory.getInstance(TrustManagerFactory.getDefaultAlgorithm());
            var4.init((KeyStore) null);
            defaultTrustManager = chooseTrustManager(var4.getTrustManagers());
            this.localTrustManager = localTrustManager;
        }

        @Override
        public void checkClientTrusted(X509Certificate[] chain, String authType) throws CertificateException {
        }

        @Override
        public void checkServerTrusted(X509Certificate[] chain, String authType) throws CertificateException {
            try {
                defaultTrustManager.checkServerTrusted(chain, authType);
            } catch (CertificateException ce) {
                localTrustManager.checkServerTrusted(chain, authType);
            }
        }

        @Override
        public X509Certificate[] getAcceptedIssuers() {
            return new X509Certificate[0];
        }
    }

    private class UnSafeHostnameVerifier implements HostnameVerifier {
        @Override
        public boolean verify(String hostname, SSLSession session) {
            return true;
        }
    }



}

总结

以上完成springboot部分代理转发，共勉

  • 标题: springboot 部分转发（不使用拦截器）
  • 作者: 曾一峰
  • 创建于: 2022-05-10 10:16:23
  • 更新于: 2023-08-11 07:07:16
  • 链接: https://blog.csdn.net/shop_and_sleep?type=blog/2022/05/10/springboot-部分转发（不使用拦截器）/springboot-部分转发（不使用拦截器）/
  • 版权声明: 本文章采用 CC BY-NC-SA 4.0 进行许可。
 评论
此页目录
springboot 部分转发（不使用拦截器）
  1. 前言
  2. 一、Interceptor
  3. 二、/**
    1. 1.RoutingDelegate
    2. 2.HttpsUtils（https支持）
  4. 总结