Question

我在向nifi发送简单的PUT请求时遇到麻烦，基本上我想用Java代码启动nifi处理器。

错误消息-服务器返回HTTP响应代码：405的URL：http://localhost:8080/nifi-api/processors/

我应该采取什么步骤解决此405问题？ nifi api网站提供了有关rest api的高级文档，但是没有有关如何使用Java向NiFi发出正确的PUT请求的指南。

import java.io.BufferedReader;
import java.io.DataOutputStream;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.URL;

import javax.net.ssl.HttpsURLConnection;

public class HttpURLConnectionExample {

    private final String USER_AGENT = "Mozilla/5.0";

    public static void main(String[] args) throws Exception {

        HttpURLConnectionExample http = new HttpURLConnectionExample();

        System.out.println("\nTesting 2 - Send Http POST request");
        http.sendPut();

    }

    // HTTP PUT request
    private void sendPut() throws Exception {

        String url = "http://localhost:8080/nifi-api/processors/";
        URL obj = new URL(url);
        HttpURLConnection con = (HttpURLConnection) obj.openConnection();

        //add reuqest header
        con.setRequestMethod("PUT");
        con.setRequestProperty("Content-Type", "application/json");
        con.setRequestProperty("Accept", "application/json");
        con.setRequestProperty("text/javascript", "*/*");

        String urlParameters = "{\r\n" + 
                "  \"status\": {\r\n" + 
                "    \"runStatus\": \"RUNNING\"\r\n" + 
                "  },\r\n" + 
                "  \"component\": {\r\n" + 
                "    \"state\": \"RUNNING\",\r\n" + 
                "    \"id\": \"749b3133-0162-1000-9acc-f384457b160c\"\r\n" + 
                "  },\r\n" + 
                "  \"id\": \"749b3133-0162-1000-9acc-f384457b160c\",\r\n" + 
                "  \"revisions\": {\r\n" + 
                "    \"version\": 1,\r\n" + 
                "    \"clientId\": \"550c4b84-0165-1000-37be-724ed17b5329\"\r\n" + 
                "}\r\n" + 
                "  ";

        // Send post request

        con.setDoOutput(true);
        DataOutputStream wr = new DataOutputStream(con.getOutputStream());
        wr.writeBytes(urlParameters);
        wr.flush();
        wr.close();

        int responseCode = con.getResponseCode();
        System.out.println("\nSending 'POST' request to URL : " + url);
        System.out.println("Post parameters : " + urlParameters);
        System.out.println("Response Code : " + responseCode);

        BufferedReader in = new BufferedReader(
                new InputStreamReader(con.getInputStream()));
        String inputLine;
        StringBuffer response = new StringBuffer();

        while ((inputLine = in.readLine()) != null) {
            response.append(inputLine);
        }
        in.close();

        //print result
        System.out.println(response.toString());

    }

}

Answer 1

A 405表示所使用的URL不支持HTTP方法（在这种情况下为PUT）。这是因为/ processors仅支持GET请求以检索可用的处理器。为了更新处理器，URL为/ processors / {processorId}，其中用要更新的给定处理器ID替换了ProcessorId。

通常，学习NiFi的REST API的最好方法是打开一个工具，例如Chrome的Dev工具，然后查看网络以查看在从UI执行所需操作时发出的请求。这些将显示URL，参数和请求/响应正文。

更新

这是UI在启动UpdateAttribute处理器时发送的内容，该处理器将PUT设置为http://localhost:8080/nifi-api/processors/5817008a-0165-1000-0bf3-2c44fde14c37

{
  "revision":{
    "clientId":"61a9ab71-0165-1000-777c-c7538789246c",
    "version":0
    },
    "component":{
      "id":"5817008a-0165-1000-0bf3-2c44fde14c37",
      "state":"RUNNING"
    },
    "disconnectedNodeAcknowledged":false
}

以下是Chrome开发工具中显示的请求：

向NiFi发送Java PUT请求

1 个答案: