Değişiklikleri al

Dosyalardaki değişiklikleri izlemesi gereken Google Drive uygulamaları için changes koleksiyonu, kullanıcıyla paylaşılanlar da dahil olmak üzere tüm dosya değişikliklerini tespit etmenin etkili bir yolunu sunar. Dosya değiştiyse koleksiyon, her dosyanın mevcut durumunu sağlar.

Başlangıç sayfası jetonunu alma

Hesabın mevcut durumu için sayfa jetonu istemek üzere changes.getStartPageToken kullanın. Bu jetonu, changes.list ile ilk görüşmenizde saklayın ve kullanın.

Geçerli sayfa jetonunu almak için:

Java

drive/snippets/drive_v3/src/main/java/FetchStartPageToken.java

GitHub'da göster

import com.google.api.client.googleapis.json.GoogleJsonResponseException;
import com.google.api.client.http.HttpRequestInitializer;
import com.google.api.client.http.javanet.NetHttpTransport;
import com.google.api.client.json.gson.GsonFactory;
import com.google.api.services.drive.Drive;
import com.google.api.services.drive.DriveScopes;
import com.google.api.services.drive.model.StartPageToken;
import com.google.auth.http.HttpCredentialsAdapter;
import com.google.auth.oauth2.GoogleCredentials;
import java.io.IOException;
import java.util.Arrays;

/* Class to demonstrate use-case of Drive's fetch start page token */
public class FetchStartPageToken {

  /**
   * Retrieve the start page token for the first time.
   *
   * @return Start page token as String.
   * @throws IOException if file is not found
   */
  public static String fetchStartPageToken() throws IOException {
        /*Load pre-authorized user credentials from the environment.
        TODO(developer) - See https://developers.google.com/identity for
        guides on implementing OAuth2 for your application. */

    GoogleCredentials credentials = GoogleCredentials.getApplicationDefault()
        .createScoped(Arrays.asList(DriveScopes.DRIVE_FILE));
    HttpRequestInitializer requestInitializer = new HttpCredentialsAdapter(
        credentials);

    // Build a new authorized API client service.
    Drive service = new Drive.Builder(new NetHttpTransport(),
        GsonFactory.getDefaultInstance(),
        requestInitializer)
        .setApplicationName("Drive samples")
        .build();
    try {
      StartPageToken response = service.changes()
          .getStartPageToken().execute();
      System.out.println("Start token: " + response.getStartPageToken());

      return response.getStartPageToken();
    } catch (GoogleJsonResponseException e) {
      // TODO(developer) - handle error appropriately
      System.err.println("Unable to fetch start page token: " + e.getDetails());
      throw e;
    }
  }

}

Python

drive/snippets/drive-v3/change_snippet/fetch_start_page_token.py

GitHub'da göster

import google.auth
from googleapiclient.discovery import build
from googleapiclient.errors import HttpError


def fetch_start_page_token():
  """Retrieve page token for the current state of the account.
  Returns & prints : start page token

  Load pre-authorized user credentials from the environment.
  TODO(developer) - See https://developers.google.com/identity
  for guides on implementing OAuth2 for the application.
  """
  creds, _ = google.auth.default()

  try:
    # create drive api client
    service = build("drive", "v3", credentials=creds)

    # pylint: disable=maybe-no-member
    response = service.changes().getStartPageToken().execute()
    print(f'Start token: {response.get("startPageToken")}')

  except HttpError as error:
    print(f"An error occurred: {error}")
    response = None

  return response.get("startPageToken")


if __name__ == "__main__":
  fetch_start_page_token()

PHP

drive/snippets/drive_v3/src/DriveFetchStartPageToken.php

GitHub'da göster

<?php
use Google\Client;
use Google\Service\Drive;
# TODO - PHP client currently chokes on fetching start page token
function fetchStartPageToken()
{
    try {
        $client = new Client();
        $client->useApplicationDefaultCredentials();
        $client->addScope(Drive::DRIVE);
        $driveService = new Drive($client);
        $response = $driveService->changes->getStartPageToken();
        printf("Start token: %s\n", $response->startPageToken);
        return $response->startPageToken;
    } catch(Exception $e) {
        echo "Error Message: ".$e;
    }

}

.NET

drive/snippets/drive_v3/DriveV3Snippets/FetchStartPageToken.cs

GitHub'da göster

using Google.Apis.Auth.OAuth2;
using Google.Apis.Drive.v3;
using Google.Apis.Services;

namespace DriveV3Snippets
{
    // Class to demonstrate use-case of Drive's fetch start page token
    public class FetchStartPageToken
    {
        /// <summary>
        /// Retrieve the starting page token.
        /// </summary>
        /// <returns>start page token as String, null otherwise.</returns>
        public static string DriveFetchStartPageToken()
        {
            try
            {
                /* Load pre-authorized user credentials from the environment.
                 TODO(developer) - See https://developers.google.com/identity for
                 guides on implementing OAuth2 for your application. */
                GoogleCredential credential = GoogleCredential.GetApplicationDefault()
                    .CreateScoped(DriveService.Scope.Drive);

                // Create Drive API service.
                var service = new DriveService(new BaseClientService.Initializer
                {
                    HttpClientInitializer = credential,
                    ApplicationName = "Drive API Snippets"
                });

                var response = service.Changes.GetStartPageToken().Execute();
                // Prints the token value.
                Console.WriteLine("Start token: " + response.StartPageTokenValue);
                return response.StartPageTokenValue;
            }
            catch (Exception e)
            {
                // TODO(developer) - handle error appropriately
                if (e is AggregateException)
                {
                    Console.WriteLine("Credential Not found");
                }
                else
                {
                    throw;
                }
            }
            return null;
        }
    }
}

Node.js

drive/snippets/drive_v3/change_snippets/fetch_start_page_token.js

GitHub'da göster

import {GoogleAuth} from 'google-auth-library';
import {google} from 'googleapis';

/**
 * Fetches the start page token for the current state of the account.
 * @return {Promise<string>} The start page token.
 */
async function fetchStartPageToken() {
  // Authenticate with Google and get an authorized client.
  // TODO (developer): Use an appropriate auth mechanism for your app.
  const auth = new GoogleAuth({
    scopes: 'https://www.googleapis.com/auth/drive.appdata',
  });

  // Create a new Drive API client (v3).
  const service = google.drive({version: 'v3', auth});

  // Fetch the start page token.
  const res = await service.changes.getStartPageToken({});
  const token = res.data.startPageToken;
  console.log('start token: ', token);
  if (!token) {
    throw new Error('Start page token not found.');
  }
  return token;
}

Değişiklikleri alma

Şu anda oturum açmış kullanıcının değişiklik listesini almak için changes.list bölümünde ayrıntılı olarak açıklandığı gibi GET koleksiyonuna istek gönderin.changes

changes koleksiyonundaki girişler kronolojik sıradadır (en eski değişiklikler önce gösterilir). includeRemoved ve restrictToMyDrive sorgu parametreleri, yanıtta kaldırılan veya paylaşılan öğelerin yer alıp almayacağını belirler.

Java

drive/snippets/drive_v3/src/main/java/FetchChanges.java

GitHub'da göster

import com.google.api.client.googleapis.json.GoogleJsonResponseException;
import com.google.api.client.http.HttpRequestInitializer;
import com.google.api.client.http.javanet.NetHttpTransport;
import com.google.api.client.json.gson.GsonFactory;
import com.google.api.services.drive.Drive;
import com.google.api.services.drive.DriveScopes;
import com.google.api.services.drive.model.ChangeList;
import com.google.auth.http.HttpCredentialsAdapter;
import com.google.auth.oauth2.GoogleCredentials;
import java.io.IOException;
import java.util.Arrays;

/* Class to demonstrate use-case of Drive's fetch changes in file. */
public class FetchChanges {
  /**
   * Retrieve the list of changes for the currently authenticated user.
   *
   * @param savedStartPageToken Last saved start token for this user.
   * @return Saved token after last page.
   * @throws IOException if file is not found
   */
  public static String fetchChanges(String savedStartPageToken) throws IOException {

        /*Load pre-authorized user credentials from the environment.
        TODO(developer) - See https://developers.google.com/identity for
        guides on implementing OAuth2 for your application.*/
    GoogleCredentials credentials = GoogleCredentials.getApplicationDefault()
        .createScoped(Arrays.asList(DriveScopes.DRIVE_FILE));
    HttpRequestInitializer requestInitializer = new HttpCredentialsAdapter(
        credentials);

    // Build a new authorized API client service.
    Drive service = new Drive.Builder(new NetHttpTransport(),
        GsonFactory.getDefaultInstance(),
        requestInitializer)
        .setApplicationName("Drive samples")
        .build();
    try {
      // Begin with our last saved start token for this user or the
      // current token from getStartPageToken()
      String pageToken = savedStartPageToken;
      while (pageToken != null) {
        ChangeList changes = service.changes().list(pageToken)
            .execute();
        for (com.google.api.services.drive.model.Change change : changes.getChanges()) {
          // Process change
          System.out.println("Change found for file: " + change.getFileId());
        }
        if (changes.getNewStartPageToken() != null) {
          // Last page, save this token for the next polling interval
          savedStartPageToken = changes.getNewStartPageToken();
        }
        pageToken = changes.getNextPageToken();
      }

      return savedStartPageToken;
    } catch (GoogleJsonResponseException e) {
      // TODO(developer) - handle error appropriately
      System.err.println("Unable to fetch changes: " + e.getDetails());
      throw e;
    }
  }
}

Python

drive/snippets/drive-v3/change_snippet/fetch_changes.py

GitHub'da göster

import google.auth
from googleapiclient.discovery import build
from googleapiclient.errors import HttpError


def fetch_changes(saved_start_page_token):
  """Retrieve the list of changes for the currently authenticated user.
      prints changed file's ID
  Args:
      saved_start_page_token : StartPageToken for the current state of the
      account.
  Returns: saved start page token.

  Load pre-authorized user credentials from the environment.
  TODO(developer) - See https://developers.google.com/identity
  for guides on implementing OAuth2 for the application.
  """
  creds, _ = google.auth.default()
  try:
    # create drive api client
    service = build("drive", "v3", credentials=creds)

    # Begin with our last saved start token for this user or the
    # current token from getStartPageToken()
    page_token = saved_start_page_token
    # pylint: disable=maybe-no-member

    while page_token is not None:
      response = (
          service.changes().list(pageToken=page_token, spaces="drive").execute()
      )
      for change in response.get("changes"):
        # Process change
        print(f'Change found for file: {change.get("fileId")}')
      if "newStartPageToken" in response:
        # Last page, save this token for the next polling interval
        saved_start_page_token = response.get("newStartPageToken")
      page_token = response.get("nextPageToken")

  except HttpError as error:
    print(f"An error occurred: {error}")
    saved_start_page_token = None

  return saved_start_page_token


if __name__ == "__main__":
  # saved_start_page_token is the token number
  fetch_changes(saved_start_page_token=209)

PHP

drive/snippets/drive_v3/src/DriveFetchChanges.php

GitHub'da göster

<?php
use Google\Client;
use Google\Service\Drive;
# TODO - PHP client currently chokes on fetching start page token
function fetchChanges()
{
    try {
        $client = new Client();
        $client->useApplicationDefaultCredentials();
        $client->addScope(Drive::DRIVE);
        $driveService = new Drive($client);
        # Begin with our last saved start token for this user or the
        # current token from getStartPageToken()
        $savedStartPageToken = readLine("Enter Start Page Token: ");
        $pageToken = $savedStartPageToken;
        while ($pageToken != null) {
            $response = $driveService->changes->listChanges($pageToken, array(
                'spaces' => 'drive'
            ));
            foreach ($response->changes as $change) {
                // Process change
                printf("Change found for file: %s", $change->fileId);
            }
            if ($response->newStartPageToken != null) {
                // Last page, save this token for the next polling interval
                $savedStartPageToken = $response->newStartPageToken;
            }
            $pageToken = $response->nextPageToken;
        }
        echo $savedStartPageToken;
    } catch(Exception $e) {
        echo "Error Message: ".$e;
    }

}
require_once 'vendor/autoload.php';

.NET

drive/snippets/drive_v3/DriveV3Snippets/FetchChanges.cs

GitHub'da göster

using Google.Apis.Auth.OAuth2;
using Google.Apis.Drive.v3;
using Google.Apis.Services;

namespace DriveV3Snippets
{
    // Class to demonstrate use-case of Drive's fetch changes in file.
    public class FetchChanges
    {
        /// <summary>
        /// Retrieve the list of changes for the currently authenticated user.
        /// prints changed file's ID
        /// </summary>
        /// <param name="savedStartPageToken">last saved start token for this user.</param>
        /// <returns>saved token for the current state of the account, null otherwise.</returns>
        public static string DriveFetchChanges(string savedStartPageToken)
        {
            try
            {
                /* Load pre-authorized user credentials from the environment.
                 TODO(developer) - See https://developers.google.com/identity for
                 guides on implementing OAuth2 for your application. */
                GoogleCredential credential = GoogleCredential.GetApplicationDefault()
                    .CreateScoped(DriveService.Scope.Drive);

                // Create Drive API service.
                var service = new DriveService(new BaseClientService.Initializer
                {
                    HttpClientInitializer = credential,
                    ApplicationName = "Drive API Snippets"
                });

                // Begin with our last saved start token for this user or the
                // current token from GetStartPageToken()
                string pageToken = savedStartPageToken;
                while (pageToken != null)
                {
                    var request = service.Changes.List(pageToken);
                    request.Spaces = "drive";
                    var changes = request.Execute();
                    foreach (var change in changes.Changes)
                    {
                        // Process change
                        Console.WriteLine("Change found for file: " + change.FileId);
                    }

                    if (changes.NewStartPageToken != null)
                    {
                        // Last page, save this token for the next polling interval
                        savedStartPageToken = changes.NewStartPageToken;
                    }
                    pageToken = changes.NextPageToken;
                }
                return savedStartPageToken;
            }
            catch (Exception e)
            {
                // TODO(developer) - handle error appropriately
                if (e is AggregateException)
                {
                    Console.WriteLine("Credential Not found");
                }
                else
                {
                    throw;
                }
            }
            return null;
        }
    }
}

Node.js

drive/snippets/drive_v3/change_snippets/fetch_changes.js

GitHub'da göster

import {GoogleAuth} from 'google-auth-library';
import {google} from 'googleapis';

/**
 * Fetches the list of changes for the currently authenticated user.
 * @param {string} savedStartPageToken The page token obtained from `fetch_start_page_token.js`.
 */
async function fetchChanges(savedStartPageToken) {
  // Authenticate with Google and get an authorized client.
  // TODO (developer): Use an appropriate auth mechanism for your app.
  const auth = new GoogleAuth({
    scopes: 'https://www.googleapis.com/auth/drive.readonly',
  });

  // Create a new Drive API client (v3).
  const service = google.drive({version: 'v3', auth});

  // The page token for the next page of changes.
  let pageToken = savedStartPageToken;

  // Loop to fetch all changes, handling pagination.
  do {
    const result = await service.changes.list({
      pageToken: savedStartPageToken,
      fields: '*',
    });

    // Process the changes.
    (result.data.changes ?? []).forEach((change) => {
      console.log('change found for file: ', change.fileId);
    });

    // Update the page token for the next iteration.
    pageToken = result.data.newStartPageToken ?? '';
  } while (pageToken);
}

Yanıt içindeki changes koleksiyonu nextPageToken içerebilir. nextPageToken listeleniyorsa değişikliklerin sonraki sayfasını toplamak için kullanılabilir. Listelenmiyorsa istemci uygulaması, gelecekte kullanılmak üzere yanıttaki newStartPageToken değerini saklamalıdır. Sayfa jetonu depolandığında, istemci uygulaması gelecekteki değişiklikler için tekrar sorgu göndermeye hazır olur.

Bildirimleri alma

Değişiklik günlüğündeki güncellemelere abone olmak için changes.watch yöntemini kullanın. Bildirimlerde değişikliklerle ilgili ayrıntılar yer almaz. Bunun yerine, yeni değişikliklerin kullanıma sunulduğunu belirtirler. Gerçek değişiklikleri almak için Değişiklikleri alma bölümünde açıklandığı gibi değişiklik feed'ini yoklayın.

Not: changes.watch içinde belgelenmemiş olsa da yöntem, changes.list parametresine benzer bir pageToken parametresi gerektirir. Bu kod changes.getStartPageToken adresinden alınabilir.

Daha fazla bilgi için Kaynak değişiklikleriyle ilgili bildirimler başlıklı makaleyi inceleyin.