Java对接Dify API接口的完整流程

<!-- HttpClient -->
<dependency>
    <groupId>org.apache.httpcomponents</groupId>
    <artifactId>httpclient</artifactId>
    <version>4.5.13</version>
</dependency>

<!-- JSON处理 -->
<dependency>
    <groupId>com.fasterxml.jackson.core</groupId>
    <artifactId>jackson-databind</artifactId>
    <version>2.13.3</version>
</dependency>

import org.apache.http.HttpEntity;
import org.apache.http.client.methods.CloseableHttpResponse;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.entity.StringEntity;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.HttpClients;
import org.apache.http.util.EntityUtils;

public class DifyApiClient {
    private static final String API_BASE_URL = "https://api.dify.ai/v1";
    private final String apiKey;
    
    public DifyApiClient(String apiKey) {
        this.apiKey = apiKey;
    }
    
    public String post(String endpoint, String requestBody) throws Exception {
        try (CloseableHttpClient httpClient = HttpClients.createDefault()) {
            HttpPost httpPost = new HttpPost(API_BASE_URL + endpoint);
            
            // 设置请求头
            httpPost.setHeader("Authorization", "Bearer " + apiKey);
            httpPost.setHeader("Content-Type", "application/json");
            
            // 设置请求体
            httpPost.setEntity(new StringEntity(requestBody));
            
            // 执行请求
            try (CloseableHttpResponse response = httpClient.execute(httpPost)) {
                HttpEntity entity = response.getEntity();
                return EntityUtils.toString(entity);
            }
        }
    }
}

import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.databind.node.ObjectNode;

public class TextGenerationExample {
    public static void main(String[] args) {
        String apiKey = "your_api_key_here";
        DifyApiClient client = new DifyApiClient(apiKey);
        
        ObjectMapper mapper = new ObjectMapper();
        ObjectNode requestBody = mapper.createObjectNode();
        requestBody.put("prompt", "请用Java写一个快速排序算法");
        requestBody.put("max_tokens", 1000);
        
        try {
            String response = client.post("/completions", requestBody.toString());
            System.out.println("API响应: " + response);
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

// 使用WebSocket实现流式响应
import javax.websocket.*;
import java.net.URI;

@ClientEndpoint
public class DifyStreamClient {
    private Session session;
    
    public void connect(String wsUrl) throws Exception {
        WebSocketContainer container = ContainerProvider.getWebSocketContainer();
        container.connectToServer(this, new URI(wsUrl));
    }
    
    @OnOpen
    public void onOpen(Session session) {
        this.session = session;
        System.out.println("连接已建立");
    }
    
    @OnMessage
    public void onMessage(String message) {
        System.out.println("收到消息: " + message);
    }
    
    public void sendMessage(String message) throws Exception {
        session.getBasicRemote().sendText(message);
    }
}

public class DifyApiException extends RuntimeException {
    private final int statusCode;
    private final String errorResponse;
    
    public DifyApiException(int statusCode, String errorResponse) {
        super("API请求失败，状态码: " + statusCode);
        this.statusCode = statusCode;
        this.errorResponse = errorResponse;
    }
    
    // getter方法...
}

// 在DifyApiClient中修改post方法
if (response.getStatusLine().getStatusCode() != 200) {
    throw new DifyApiException(
        response.getStatusLine().getStatusCode(),
        EntityUtils.toString(entity)
    );
}

PoolingHttpClientConnectionManager cm = new PoolingHttpClientConnectionManager();
cm.setMaxTotal(200);
cm.setDefaultMaxPerRoute(20);

RequestConfig config = RequestConfig.custom()
    .setConnectTimeout(5000)
    .setSocketTimeout(15000)
    .build();

HttpRequestRetryHandler retryHandler = (exception, executionCount, context) -> {
    return executionCount <= 3 && exception instanceof NoHttpResponseException;
};