파일 변경사항을 추적해야 하는 Google Drive 앱의 경우 changes 컬렉션을 사용하면 사용자와 공유한 파일을 비롯한 모든 파일 변경사항을 효율적으로 감지할 수 있습니다. 파일이 변경된 경우 컬렉션은 각 파일의 현재 상태를 제공합니다.
시작 페이지 토큰 가져오기
계정의 현재 상태에 대한 페이지 토큰을 요청하려면 changes.getStartPageToken를 사용합니다.
changes.list를 처음 호출할 때 이 토큰을 저장하고 사용합니다.
현재 페이지 토큰을 가져오는 방법은 다음과 같습니다.
Java
drive/snippets/drive_v3/src/main/java/FetchStartPageToken.java
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
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()
2,399필리핀
drive/snippets/drive_v3/src/DriveFetchStartPageToken.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
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
/**
* Retrieve page token for the current state of the account.
**/
async function fetchStartPageToken() {
// Get credentials and build service
// TODO (developer) - Use appropriate auth mechanism for your app
const {GoogleAuth} = require('google-auth-library');
const {google} = require('googleapis');
const auth = new GoogleAuth({
scopes: 'https://www.googleapis.com/auth/drive.appdata',
});
const service = google.drive({version: 'v3', auth});
try {
const res = await service.changes.getStartPageToken({});
const token = res.data.startPageToken;
console.log('start token: ', token);
return token;
} catch (err) {
// TODO(developer) - Handle error
throw err;
}
}
변경사항 가져오기
현재 로그인한 사용자의 변경사항 목록을 가져오려면 changes.list에 설명된 대로 GET 요청을 changes 컬렉션에 보냅니다.
changes 컬렉션의 항목은 시간순으로 표시됩니다 (가장 오래된 변경사항이 먼저 표시됨). includeRemoved 및 restrictToMyDrive 쿼리 매개변수는 응답에 삭제된 항목이나 공유 항목을 포함해야 하는지 여부를 결정합니다.
Java
drive/snippets/drive_v3/src/main/java/FetchChanges.java
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
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)
2,399필리핀
drive/snippets/drive_v3/src/DriveFetchChanges.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
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
/**
* Retrieve the list of changes for the currently authenticated user.
* @param {string} savedStartPageToken page token got after executing fetch_start_page_token.js file
**/
async function fetchChanges(savedStartPageToken) {
// Get credentials and build service
// TODO (developer) - Use appropriate auth mechanism for your app
const {GoogleAuth} = require('google-auth-library');
const {google} = require('googleapis');
const auth = new GoogleAuth({
scopes: 'https://www.googleapis.com/auth/drive.readonly',
});
const service = google.drive({version: 'v3', auth});
try {
let pageToken = savedStartPageToken;
do {
const res = await service.changes.list({
pageToken: savedStartPageToken,
fields: '*',
});
res.data.changes.forEach((change) => {
console.log('change found for file: ', change.fileId);
});
pageToken = res.data.newStartPageToken;
return pageToken;
} while (pageToken);
} catch (err) {
// TODO(developer) - Handle error
throw err;
}
}
응답의 changes 컬렉션에는 nextPageToken가 포함될 수 있습니다. nextPageToken가 나열되면 변경사항의 다음 페이지를 수집하는 데 사용할 수 있습니다. 목록에 없으면 클라이언트 애플리케이션은 나중에 사용할 수 있도록 newStartPageToken를 응답에 저장해야 합니다. 페이지 토큰이 저장되면 클라이언트 애플리케이션이 향후 변경사항을 위해 다시 쿼리할 준비가 됩니다.
알림 수신
changes.watch 메서드를 사용하여 변경 로그의 업데이트를 구독합니다. 알림에는 변경사항에 관한 세부정보가 포함되지 않습니다. 대신 새 변경사항이 있음을 나타냅니다. 실제 변경사항을 가져오려면 변경사항 가져오기에 설명된 대로 변경 피드를 폴링합니다.
자세한 내용은 리소스 변경 알림을 참고하세요.