为什么调用这个Web服务时，我得到一个404错误？

Question

我需要调用Java中（Java8）一对夫妇的Web服务。第一个创建相关的一些元数据的新idenifier（DOI）（autoGenerateDOI（...））。所述第二寄存器的URL针对该标识符（REGISTERURL（...）。

第一个呼叫成功的工作，但是当我试图让第二个呼叫我得到一个404错误作为响应。我试图建立一个独立的程序来证明我在做什么（下）。任何人都可以指出我做错了什么？

谢谢。

import java.net.HttpURLConnection;
import javax.net.ssl.HttpsURLConnection;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import java.net.MalformedURLException;
import java.net.URL;
import java.util.Scanner;


public class DOIdebugger {


    public static String autoGenerateDOI(String doi, String creator, String title, String publisher, String publicationDate, String hostname){

        String doiGenerated = "notYetCreated";

        StringBuffer payload = new StringBuffer();
        payload.append("<?xml version=\"1.0\" encoding=\"UTF-8\"?>");
        payload.append("<resource xmlns:xsi=\"http://www.w3.org/2001/XMLSchema-instance\" xmlns=\"http://datacite.org/schema/kernel-4\" xsi:schemaLocation=\"http://datacite.org/schema/kernel-4 http://schema.datacite.org/meta/kernel-4.1/metadata.xsd\">");
        payload.append("<identifier identifierType=\"DOI\"></identifier>");
        payload.append("<creators>");
        payload.append("<creator>");
        payload.append("<creatorName>Creator Name</creatorName>");
        payload.append("<nameIdentifier nameIdentifierScheme=\"ISNI\">Not available</nameIdentifier>");
        payload.append("</creator>");
        payload.append("</creators>");
        payload.append("<titles>");
        payload.append("<title>Test DOI creation</title>");
        payload.append("<title titleType=\"Subtitle\">A DataShare</title>");
        payload.append("</titles>");
        payload.append("<publisher>abcxyz123</publisher");
        payload.append("<publicationYear>2019</publicationYear>");
        payload.append("<resourceType resourceTypeGeneral=\"Dataset\">Dataset</resourceType>");
        payload.append("</resource>");

        System.out.println("DatasetUtility::registerURL():: metadata payload=" + payload.toString());

        try {

            URL url = new URL("https://mds.test.datacite.org/metadata/10.17639");

            HttpsURLConnection metaDataConnection;

            metaDataConnection = initiateHttpsURLConnection(hostname, url, payload.toString().length());

            System.out.println("metaDataConnection.getRequestMethod() = " + metaDataConnection.getRequestMethod());

            OutputStreamWriter metaWriter = new OutputStreamWriter( metaDataConnection.getOutputStream() );

            metaWriter.write(payload.toString());
            metaWriter.flush();
            metaWriter.close();

            if(metaDataConnection.getResponseCode() == 200 || metaDataConnection.getResponseCode() == 201){
                InputStreamReader reader = new InputStreamReader( metaDataConnection.getInputStream() );

                StringBuilder response = new StringBuilder();

                Scanner scanner = new Scanner(reader);
                while(scanner.hasNext()) {
                    response.append(scanner.next());
                }
                scanner.close();

                System.out.println( "\nResponse from server after POST:\n" + response );
                doiGenerated = response.substring(3, (response.length()-1));
                System.out.println( "\nDOI Generated:" + doiGenerated );
            }

            metaDataConnection.disconnect();

        } catch (MalformedURLException malformedURLException) {
            System.out.println("" + malformedURLException.getMessage());
        } catch (IOException ioException) {
            System.out.println("" + ioException.getMessage());
        }


        return doiGenerated;
    }

    public static String registerURL(String doi, String creator, String title, String publisher, String publicationDate, String hostname){

        StringBuffer payload = new StringBuffer();
        HttpURLConnection registerURLConnection = null;

        try {

            URL url = new URL("https://mds.test.datacite.org/doi/" + doi );

            //construct payload
            payload.append("doi=" + doi + "\nurl=https://www.example.com");
            System.out.println("DatasetUtility::registerURL()::RegisterURL payload=\n*****\n" + payload.toString()
                    + "\n*****\nlength=" + payload.toString().length());

            registerURLConnection = initiateHttpsURLConnection(hostname, url, payload.toString().length());
            System.out.println("DatasetUtility::registerURL():: RegisterURL::\nurl=" + registerURLConnection.getURL());
            System.out.println("registerURLConnection.getRequestMethod() = " + registerURLConnection.getRequestMethod());

            //send request
            OutputStreamWriter registerURLWriter = new OutputStreamWriter( registerURLConnection.getOutputStream() );

            registerURLWriter.write(payload.toString());
            registerURLWriter.flush();
            registerURLWriter.close();

            int responseCode = registerURLConnection.getResponseCode();

            System.out.println("DatasetUtility::registerURL():: RegisterURL:: connection response=" + responseCode);

            if (responseCode!=200 || responseCode!=201){
                System.out.println("Error on registering URL for DOI");
                System.out.println("registerURLConnection msg= " + registerURLConnection.getResponseMessage());

                Scanner scanner = new Scanner(registerURLConnection.getErrorStream());
                while(scanner.hasNext()) {
                    System.out.println("ErrorStream: " + scanner.next());
                }
                scanner.close();

            } else {
                System.out.println("Successfully registered URL.  Response code:" + responseCode);
            }

        } catch (MalformedURLException malformedURLException) {
            System.out.println("MFE:" + malformedURLException.getMessage());
        } catch (IOException ioException) {
            System.out.println("IOE:" + ioException.getMessage());
        }

        return "Successful";
    }

    private static HttpsURLConnection initiateHttpsURLConnection(String hostname, URL url, int contentLength) throws IOException {

        System.out.println("\nHostname: " + hostname + "\turl:" + url + "\tcontentLength:" + contentLength + "\n");

        HttpsURLConnection httpsURLConnection  = null;

        httpsURLConnection  = (HttpsURLConnection) url.openConnection();
        httpsURLConnection.setDoOutput(true);
        httpsURLConnection.setRequestProperty("Authorization", "Basic " + edu.purdue.cybercenter.instance.actions.dataset.Base64.encodeToString("my_username:my_password".getBytes(), false) );
        httpsURLConnection.setRequestMethod("POST");
        httpsURLConnection.setRequestProperty("Content-Type", "text/plain;charset=UTF-8");
        System.out.println("Set content length = " + contentLength);


        return httpsURLConnection;

    }


    public static void main(String[] args){
        String newDOI = autoGenerateDOI("doi", "abcxyz123", "Autogeneration of DOIs", "Creator Name", "2019", "www.example.com");
        System.out.println("************************************************************************************");
        registerURL(newDOI, "abcxyz123", "Autogeneration of DOIs", "Creator Name", "2019", "www.example.com");
    }
}

一个例子输出从哪个是：

DatasetUtility::registerURL():: metadata payload=<?xml version="1.0" encoding="UTF-8"?><resource xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://datacite.org/schema/kernel-4" xsi:schemaLocation="http://datacite.org/schema/kernel-4 http://schema.datacite.org/meta/kernel-4.1/metadata.xsd"><identifier identifierType="DOI"></identifier><creators><creator><creatorName>Creator Name</creatorName><nameIdentifier nameIdentifierScheme="ISNI">Not available</nameIdentifier></creator></creators><titles><title>Test DOI creation</title><title titleType="Subtitle">A DataShare</title></titles><publisher>abcxyz123</publisher<publicationYear>2019</publicationYear><resourceType resourceTypeGeneral="Dataset">Dataset</resourceType></resource>

Hostname: www.example.com   url:https://mds.test.datacite.org/metadata/10.17639 contentLength:701

Set content length = 701
metaDataConnection.getRequestMethod() = POST

Response from server after POST:
OK(10.17639/D4YJ-6075)

DOI Generated:10.17639/D4YJ-6075
************************************************************************************
DatasetUtility::registerURL()::RegisterURL payload=
*****
doi=10.17639/D4YJ-6075
url=https://www.example.com
*****
length=50

Hostname: www.example.com   url:https://mds.test.datacite.org/doi/10.17639/D4YJ-6075    contentLength:50

Set content length = 50
DatasetUtility::registerURL():: RegisterURL::
url=https://mds.test.datacite.org/doi/10.17639/D4YJ-6075
registerURLConnection.getRequestMethod() = POST
DatasetUtility::registerURL():: RegisterURL:: connection response=404
Error on registering URL for DOI
registerURLConnection msg= Not Found
ErrorStream: Resource
ErrorStream: not
ErrorStream: found

然而，使用“弧线”上以相同的目标URL和相同的“有效载荷”的命令行调用WebService的成功。

curl  -X PUT -H "Content-Type: text/plain;charset=UTF-8" --user my_username:my_password --data $'doi=10.17639/D4YJ-6075\nurl=http://example.org/' https://mds.test.datacite.org/doi/10.17639/D4YJ-6075

Answer 1

正如莫里斯·佩里的评论，我用错了请求方法。