在OAuth中使用Java2.0和Google Spreadsheet API的示例是什么？

Question

展示如何使用Google Data Java Client Library及其对Google Spreadsheet API (现在称为Google Sheets API)的OAuth 2.0支持的示例代码在哪里？

Answer 1

答案已从原始问题移至匹配网站的"Q and A“格式。

Google Data Java Client Library支持OAuth 2.0。不幸的是，库中没有完整的示例来说明如何在Google Spreadsheet API中使用它。

这是一个对我很有效的例子。我希望有人发现它是有帮助的。

import com.google.api.client.auth.oauth2.Credential;
import com.google.api.client.googleapis.auth.oauth2.GoogleAuthorizationCodeRequestUrl;
import com.google.api.client.googleapis.auth.oauth2.GoogleAuthorizationCodeTokenRequest;
import com.google.api.client.googleapis.auth.oauth2.GoogleCredential;
import com.google.api.client.googleapis.auth.oauth2.GoogleTokenResponse;
import com.google.api.client.http.HttpTransport;
import com.google.api.client.http.javanet.NetHttpTransport;
import com.google.api.client.json.jackson.JacksonFactory;
import com.google.gdata.util.ServiceException;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.Arrays;
import java.util.List;

public class NewClass {

  // Retrieve the CLIENT_ID and CLIENT_SECRET from an APIs Console project:
  //     https://code.google.com/apis/console
  static String CLIENT_ID = "your-client-id";
  static String CLIENT_SECRET = "your-client-secret";
  // Change the REDIRECT_URI value to your registered redirect URI for web
  // applications.
  static String REDIRECT_URI = "the-redirect-uri";
  // Add other requested scopes.
  static List<String> SCOPES = Arrays.asList("https://spreadsheets.google.com/feeds");


public static void main (String args[]) throws IOException, ServiceException, com.google.protobuf.ServiceException{
    Credential credencial = getCredentials();
    JavaApplication20.printDocuments(credencial);
}


  /**
   * Retrieve OAuth 2.0 credentials.
   * 
   * @return OAuth 2.0 Credential instance.
   */
  static Credential getCredentials() throws IOException {
    HttpTransport transport = new NetHttpTransport();
    JacksonFactory jsonFactory = new JacksonFactory();

    // Step 1: Authorize -->
    String authorizationUrl =
        new GoogleAuthorizationCodeRequestUrl(CLIENT_ID, REDIRECT_URI, SCOPES).build();

    // Point or redirect your user to the authorizationUrl.
    System.out.println("Go to the following link in your browser:");
    System.out.println(authorizationUrl);

    // Read the authorization code from the standard input stream.
    BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
    System.out.println("What is the authorization code?");
    String code = in.readLine();
    // End of Step 1 <--

    // Step 2: Exchange -->
    GoogleTokenResponse response =
        new GoogleAuthorizationCodeTokenRequest(transport, jsonFactory, CLIENT_ID, CLIENT_SECRET,
            code, REDIRECT_URI).execute();
    // End of Step 2 <--

    // Build a new GoogleCredential instance and return it.
    return new GoogleCredential.Builder().setClientSecrets(CLIENT_ID, CLIENT_SECRET)
        .setJsonFactory(jsonFactory).setTransport(transport).build()
     .setAccessToken(response.getAccessToken()).setRefreshToken(response.getRefreshToken());
  }

  // …
}

下面是另一个类：

import com.google.api.client.auth.oauth2.Credential;
import com.google.gdata.client.docs.DocsService;
import com.google.gdata.client.spreadsheet.SpreadsheetService;
import com.google.gdata.data.docs.DocumentListEntry;
import com.google.gdata.data.docs.DocumentListFeed;
import com.google.gdata.data.docs.SpreadsheetEntry;
import com.google.gdata.data.spreadsheet.CellEntry;
import com.google.gdata.data.spreadsheet.CellFeed;
import com.google.gdata.data.spreadsheet.SpreadsheetFeed;
import com.google.gdata.data.spreadsheet.WorksheetEntry;
import com.google.gdata.data.spreadsheet.WorksheetFeed;
import com.google.gdata.util.ServiceException;
// ...
import java.io.IOException;
import java.net.URL;
import java.util.List;
// ...

public class JavaApplication20 {
  // …

  static void printDocuments(Credential credential) throws IOException, ServiceException {
    // Instantiate and authorize a new SpreadsheetService object.

     SpreadsheetService service =
            new SpreadsheetService("Aplication-name");
     service.setOAuth2Credentials(credential);
    // Send a request to the Documents List API to retrieve document entries.
    URL SPREADSHEET_FEED_URL = new URL(
        "https://spreadsheets.google.com/feeds/spreadsheets/private/full");
    // Make a request to the API and get all spreadsheets.
    SpreadsheetFeed feed = service.getFeed(SPREADSHEET_FEED_URL,
        SpreadsheetFeed.class);
    List<com.google.gdata.data.spreadsheet.SpreadsheetEntry> spreadsheets = feed.getEntries();
     if (spreadsheets.isEmpty()) {
      // TODO: There were no spreadsheets, act accordingly.
    }
com.google.gdata.data.spreadsheet.SpreadsheetEntry spreadsheet = spreadsheets.get(0);
    System.out.println(spreadsheet.getTitle().getPlainText());
// Get the first worksheet of the first spreadsheet.
    // TODO: Choose a worksheet more intelligently based on your
    // app's needs.
    WorksheetFeed worksheetFeed = service.getFeed(
        spreadsheet.getWorksheetFeedUrl(), WorksheetFeed.class);
    List<WorksheetEntry> worksheets = worksheetFeed.getEntries();
    WorksheetEntry worksheet = worksheets.get(0);

    // Fetch the cell feed of the worksheet.
    URL cellFeedUrl = worksheet.getCellFeedUrl();
    CellFeed cellFeed = service.getFeed(cellFeedUrl, CellFeed.class);

    // Iterate through each cell, printing its value.
    for (CellEntry cell : cellFeed.getEntries()) {
      // Print the cell's address in A1 notation
      System.out.print(cell.getTitle().getPlainText() + "\t");
      // Print the cell's address in R1C1 notation
      System.out.print(cell.getId().substring(cell.getId().lastIndexOf('/') + 1) + "\t");
      // Print the cell's formula or text value
      System.out.print(cell.getCell().getInputValue() + "\t");
      // Print the cell's calculated value if the cell's value is numeric
      // Prints empty string if cell's value is not numeric
      System.out.print(cell.getCell().getNumericValue() + "\t");
      // Print the cell's displayed value (useful if the cell has a formula)
      System.out.println(cell.getCell().getValue() + "\t");
    }

  }

  // ...
}

Answer 2

你可以通过示例here找到逐步的解释。因此，您的代码可能如下所示：

SpreadsheetService service = new SpreadsheetService("MySpreadsheetIntegration-v1");
service.setProtocolVersion(SpreadsheetService.Versions.V1); // It's important to specify the version

service.setRequestFactory(makeAuthorization());

SpreadsheetQuery q = new SpreadsheetQuery(new URL(DEFAULT_SPREADSHEET_QUERY));

SpreadsheetFeed feed;
try {
  feed = service.query(q, SpreadsheetFeed.class);
}
catch (AuthenticationException e) {
  refreshAccessToken(service);

  feed = service.query(q, SpreadsheetFeed.class);
}

SpreadsheetEntry spreadsheet = findSpreadSheet(feed);

...

// do your stuff

...

// a couple of utility methods are used above:

private void refreshAccessToken(SpreadsheetService service) throws Exception {
  String accessToken = callGetAccessTokenApi();

  // save access token

  service.getRequestFactory().setAuthToken(new GoogleAuthTokenFactory.OAuth2Token(new GoogleCredential().setAccessToken(accessToken)));
}

//private static final String GOOGLE_API_HOST = "https://www.googleapis.com/";

private String callGetAccessTokenApi() throws Exception {
  HttpClient client = HttpClients.createDefault();

  String url = String.format(
    "%soauth2/v3/token?client_id=%s&client_secret=%s&refresh_token=%s&grant_type=refresh_token",
    GOOGLE_API_HOST,
    googleAuthorization.getClientId(),
    googleAuthorization.getClientSecret(),
    googleAuthorization.getRefreshToken()
  );
  HttpPost post = new HttpPost(url);
  post.addHeader(ACCEPT_HEADER_NAME, "application/x-www-form-urlencoded");

  try {
    HttpResponse response = client.execute(post);

    JSONObject object = readJson(response);

    return object.getString("access_token");
  }
  finally {
    post.releaseConnection();
  }
}

private Service.GDataRequestFactory makeAuthorization() {
  Service.GDataRequestFactory requestFactory = new HttpGDataRequest.Factory();

  // load access token

  requestFactory.setAuthToken(new GoogleAuthTokenFactory.OAuth2Token(new GoogleCredential().setAccessToken(accessToken)));

  return requestFactory;
}

Answer 3

(2016年12月)这个问题的大部分和这里的大多数答案现在已经过时了，因为: 1) GData APIs是上一代的Google API。虽然并不是所有的谷歌API都被弃用，但all Google APIs do not use the Google Data protocol；以及2) 2016年的谷歌released a new Google Sheets API v4 (不是GData)。要使用新的接口，您需要获取the Google APIs Client Library for Java并使用最新的Sheets API，它比任何以前的接口都更强大、更灵活。

这里是帮助您开始使用our Java Quickstart code sample的API --其中也包含OAuth2代码。此外，下面是the JavaDocs reference for the Sheets API，它概述了您可以使用的所有类。如果你对Python不“过敏”，我还制作了一个OAuth授权码的视频，以及使用Sheets API的另两个视频，其中包含更多的“真实世界”示例：

• Accessing Google APIs: Common code walkthrough (代码深度潜水post)
• Migrating SQL data to a Sheet (代码深度潜水post)
• Formatting text using the Sheets API (代码深度潜水post)

最新的API提供了旧版本中没有的功能，即允许开发人员以编程方式访问工作表，就像使用用户界面一样(创建冻结行、执行单元格格式、调整行/列大小、添加透视表、创建图表等)。还要注意，此API主要用于如上所述的程序化电子表格操作和功能。

要执行文件级访问，例如上载和下载、导入和导出(与上载和下载相同，但可以转换为各种格式)，您可以使用Google Drive API，下面是我创建的两个示例(也是Python)：

PDF格式(简单)将谷歌表格导出为CSV (blogpost)

• (intermediate)“穷人纯文本到”转换器(blogpost) (*)

(*) - TL;DR:上传纯文本文件到驱动器，导入/转换为Google Docs格式，然后将该文档导出为PDF。上面的帖子使用了Drive API v2；this follow-up post描述了将其迁移到Drive API v3，这里有一个结合了这两篇帖子的developer video。

要了解有关如何使用Google API(主要是Python或JavaScript)的更多信息，请查看我正在制作的各种谷歌开发人员视频(series 1和series 2)。