RestTemplate进行https请求时适配信任证书

转载请注明出处：

1.http协议请求

　　使用RestTemplate进行http协议的请求时，不需要考虑证书验证相关问题，以下为使用RestTemplate直接使用的代码示例：

import org.springframework.web.client.RestTemplate;
import org.springframework.http.ResponseEntity;
import org.springframework.http.HttpMethod;
import org.springframework.http.HttpEntity;
import org.springframework.http.HttpHeaders;  

public class HttpRestClient {  

    public static void main(String[] args) {
        RestTemplate restTemplate = new RestTemplate();  

        String url = "http://example.com/api/endpoint"; // 注意这里是HTTP协议
        HttpHeaders headers = new HttpHeaders();
        // 可以在这里添加请求头，如果需要的话
        HttpEntity<?> requestEntity = new HttpEntity<>(headers);  

        try {
            ResponseEntity<String> responseEntity = restTemplate.exchange(
                url,
                HttpMethod.GET, // 或者使用其他HTTP方法，如POST、PUT等
                requestEntity,
                String.class // 指定响应体的类型
            );  

            // 处理响应
            if (responseEntity.getStatusCode().is2xxSuccessful()) {
                String responseBody = responseEntity.getBody();
                System.out.println("Response: " + responseBody);
            } else {
                System.out.println("Request failed with status: " + responseEntity.getStatusCode());
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

2.Https请求信任所有证书：

　　在Java中，使用RestTemplate进行HTTP请求时，默认情况下它会验证HTTPS证书的有效性。如果想要忽略HTTPS证书验证（这通常不推荐，因为它会降低安全性），需要自定义一个HttpClient并设置它忽略SSL证书验证。

　　以下是一个示例，展示了如何为RestTemplate创建一个自定义的HttpClient，该HttpClient将忽略HTTPS证书验证：

1. 创建一个忽略SSL证书验证的HttpClient：

import org.apache.http.conn.ssl.NoopHostnameVerifier;
import org.apache.http.conn.ssl.SSLConnectionSocketFactory;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.HttpClients;
import org.apache.http.ssl.SSLContexts;
import javax.net.ssl.SSLContext;
import java.security.KeyManagementException;
import java.security.NoSuchAlgorithmException;  

public CloseableHttpClient createTrustingHttpClient() throws NoSuchAlgorithmException, KeyManagementException {
    SSLContext sslContext = SSLContexts.custom()
            .loadTrustMaterial(null, (chain, authType) -> true) // 信任所有证书
            .build();  

    SSLConnectionSocketFactory sslsf = new SSLConnectionSocketFactory(sslContext, NoopHostnameVerifier.INSTANCE);  

    return HttpClients.custom()
            .setSSLSocketFactory(sslsf)
            .build();
}

　　2.使用自定义的HttpClient创建RestTemplate：

import org.springframework.http.client.HttpComponentsClientHttpRequestFactory;
import org.springframework.web.client.RestTemplate;  

public RestTemplate createRestTemplateWithTrustingHttpClient() throws NoSuchAlgorithmException, KeyManagementException {
    HttpComponentsClientHttpRequestFactory factory = new HttpComponentsClientHttpRequestFactory();
    factory.setHttpClient(createTrustingHttpClient());  

    return new RestTemplate(factory);
}

　　3.使用RestTemplate进行请求：

public void makeRequest() throws NoSuchAlgorithmException, KeyManagementException {
    RestTemplate restTemplate = createRestTemplateWithTrustingHttpClient();  

    String url = "https://example.com/api/endpoint";
    RequestEntity<?> requestEntity = RequestEntity.get(URI.create(url)).build();
    ResponseEntity<String> responseEntity = restTemplate.exchange(requestEntity, String.class);  

    // 处理响应...
}　　

注意：

• 忽略SSL证书验证会降低你的应用的安全性，因为它容易受到中间人攻击。在生产环境中，你应该始终验证SSL证书。

• 如果确实需要忽略证书验证，确保完全了解相关的安全风险，并在完成后尽快恢复正常的证书验证。

3.自定义加载证书

　　在Java中使用RestTemplate进行HTTPS请求时，如果需要加载特定的HTTPS证书，通常需要使用一个自定义的HttpClient，并配置SSL上下文以加载你的证书。以下是一个使用Apache HttpClient和Spring RestTemplate加载特定HTTPS证书的示例：

1. 创建自定义的HttpClient

　　需要创建一个自定义的HttpClient，并配置SSL上下文以加载你的证书。

import org.apache.http.conn.ssl.SSLConnectionSocketFactory;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.HttpClients;
import org.apache.http.ssl.SSLContexts;
import org.springframework.http.client.HttpComponentsClientHttpRequestFactory;
import org.springframework.web.client.RestTemplate;  

import javax.net.ssl.KeyManagerFactory;
import javax.net.ssl.SSLContext;
import javax.net.ssl.TrustManagerFactory;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.security.KeyStore;
import java.security.KeyStoreException;
import java.security.NoSuchAlgorithmException;
import java.security.cert.CertificateException;  

public class CustomRestTemplate {  

    public static RestTemplate createRestTemplateWithCustomSSL() throws NoSuchAlgorithmException, KeyStoreException, CertificateException, IOException {
        // 加载你的证书和私钥
        KeyStore keyStore = KeyStore.getInstance("PKCS12");
        try (InputStream certStream = new FileInputStream("path/to/your/cert.p12")) {
            keyStore.load(certStream, "password".toCharArray()); // 替换为你的证书密码
        }  

        KeyManagerFactory keyManagerFactory = KeyManagerFactory.getInstance(KeyManagerFactory.getDefaultAlgorithm());
        keyManagerFactory.init(keyStore, "password".toCharArray()); // 替换为你的证书密码  

        TrustManagerFactory trustManagerFactory = TrustManagerFactory.getInstance(TrustManagerFactory.getDefaultAlgorithm());
        trustManagerFactory.init(keyStore);  

        SSLContext sslContext = SSLContexts.custom()
                .loadKeyMaterial(keyManagerFactory, "password".toCharArray()) // 替换为你的证书密码
                .loadTrustMaterial(trustManagerFactory)
                .build();  

        SSLConnectionSocketFactory sslsf = new SSLConnectionSocketFactory(sslContext, SSLConnectionSocketFactory.NO_HOSTNAME_VERIFIER);  

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

        HttpComponentsClientHttpRequestFactory requestFactory = new HttpComponentsClientHttpRequestFactory(httpClient);
        return new RestTemplate(requestFactory);
    }
}

　　在上面的代码中，你需要替换path/to/your/cert.p12为你的证书文件路径，以及替换password为你的证书密码。

　　2.使用自定义的RestTemplate

　　现在你可以使用上面创建的RestTemplate实例进行HTTPS请求了。

public class MyService {  

    private final RestTemplate restTemplate;  

    public MyService() throws NoSuchAlgorithmException, KeyStoreException, CertificateException, IOException {
        this.restTemplate = CustomRestTemplate.createRestTemplateWithCustomSSL();
    }  

    public String makeHttpsRequest(String url) {
        return restTemplate.getForObject(url, String.class);
    }
}