Almacena datos específicos de la aplicación

La carpeta de datos de aplicación es una carpeta oculta especial que tu app puede usar para almacenar datos específicos de la aplicación, como archivos de configuración. La carpeta de datos de la aplicación se crea automáticamente cuando intentas crear un archivo en ella. Usa esta carpeta para almacenar cualquier archivo con el que el usuario no deba interactuar directamente. Solo tu aplicación puede acceder a esta carpeta, y el usuario y otras apps de Drive ocultan su contenido.

Los archivos de appDataFolder no pueden moverse entre ubicaciones de almacenamiento (espacios). Para obtener más información, consulta Organización de archivos.

La carpeta de datos de la aplicación se borra cuando un usuario desinstala tu app desde Mi unidad. Los usuarios también pueden borrar la carpeta de datos de tu app de forma manual.

Alcance de la carpeta de datos de la aplicación

Antes de acceder a la carpeta de datos de la aplicación, debes solicitar acceso al permiso https://www.googleapis.com/auth/drive.appdata. Para obtener más información sobre los permisos y cómo solicitar acceso a ellos, consulta la información específica sobre autenticación y autorización de la API. Si quieres obtener información acerca de los alcances específicos de OAuth 2.0, consulta los permisos de OAuth 2.0 para las API de Google.

Crea un archivo en la carpeta de datos de la aplicación

Para crear un archivo en la carpeta de datos de la aplicación, especifica appDataFolder en la propiedad parents del archivo y usa el método files.create a fin de subirlo. En la siguiente muestra de código, se indica cómo insertar un archivo en una carpeta mediante una biblioteca cliente.

Java

drive/snippets/drive_v3/src/main/java/UploadAppData.java
import com.google.api.client.googleapis.json.GoogleJsonResponseException;
import com.google.api.client.http.FileContent;
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.File;
import com.google.auth.http.HttpCredentialsAdapter;
import com.google.auth.oauth2.GoogleCredentials;
import java.io.IOException;
import java.util.Arrays;
import java.util.Collections;

/**
 * Class to demonstrate use-case of create file in the application data folder.
 */
public class UploadAppData {

  /**
   * Creates a file in the application data folder.
   *
   * @return Created file's Id.
   */
  public static String uploadAppData() 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 = null;
    try {
      credentials = GoogleCredentials.getApplicationDefault()
          .createScoped(Arrays.asList(DriveScopes.DRIVE_APPDATA));
    } catch (IOException e) {
      e.printStackTrace();
    }
    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 {
      // File's metadata.
      File fileMetadata = new File();
      fileMetadata.setName("config.json");
      fileMetadata.setParents(Collections.singletonList("appDataFolder"));
      java.io.File filePath = new java.io.File("files/config.json");
      FileContent mediaContent = new FileContent("application/json", filePath);
      File file = service.files().create(fileMetadata, mediaContent)
          .setFields("id")
          .execute();
      System.out.println("File ID: " + file.getId());
      return file.getId();
    } catch (GoogleJsonResponseException e) {
      // TODO(developer) - handle error appropriately
      System.err.println("Unable to create file: " + e.getDetails());
      throw e;
    }
  }

}

Python

drive/snippets/drive-v3/app_data_snippet/upload_appdata.py
from __future__ import print_function

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


def upload_appdata():
    """Insert a file in the application data folder and prints file Id.
    Returns : ID's of the inserted files

    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:
        # call drive api client
        service = build('drive', 'v3', credentials=creds)

        # pylint: disable=maybe-no-member
        file_metadata = {
            'name': 'abc.txt',
            'parents': ['appDataFolder']
        }
        media = MediaFileUpload('abc.txt',
                                mimetype='text/txt',
                                resumable=True)
        file = service.files().create(body=file_metadata, media_body=media,
                                      fields='id').execute()
        print(F'File ID: {file.get("id")}')

    except HttpError as error:
        print(F'An error occurred: {error}')
        file = None

    return file.get('id')


if __name__ == '__main__':
    upload_appdata()

Node.js

drive/snippets/drive_v3/appdata_snippets/upload_appdata.js
/**
 * Insert a file in the application data folder and prints file Id
 * */
async function uploadAppdata() {
  // 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 fs = require('fs');

  const auth = new GoogleAuth({
    scopes: 'https://www.googleapis.com/auth/drive.appdata',
  });
  const service = google.drive({version: 'v3', auth});
  const fileMetadata = {
    name: 'config.json',
    parents: ['appDataFolder'],
  };
  const media = {
    mimeType: 'application/json',
    body: fs.createReadStream('files/config.json'),
  };
  try {
    const file = await service.files.create({
      resource: fileMetadata,
      media: media,
      fields: 'id',
    });
    console.log('File Id:', file.data.id);
    return file.data.id;
  } catch (err) {
    // TODO(developer) - Handle error
    throw err;
  }
}

PHP

drive/snippets/drive_v3/src/DriveUploadAppData.php
use Google\Client;
use Google\Service\Drive;
function uploadAppData()
{
   try {
    $client = new Client();
    $client->useApplicationDefaultCredentials();
    $client->addScope(Drive::DRIVE);
    $client->addScope(Drive::DRIVE_APPDATA);
    $driveService = new Drive($client);
    $fileMetadata = new Drive\DriveFile(array(
        'name' => 'config.json',
        'parents' => array('appDataFolder')
    ));
    $content = file_get_contents('../files/config.json');
    $file = $driveService->files->create($fileMetadata, array(
        'data' => $content,
        'mimeType' => 'application/json',
        'uploadType' => 'multipart',
        'fields' => 'id'));
    printf("File ID: %s\n", $file->id);
    return $file->id;

   } catch(Exception $e) {
     echo "Error Message: ".$e;
   }  
}

.NET

drive/snippets/drive_v3/DriveV3Snippets/UploadAppData.cs
using Google.Apis.Auth.OAuth2;
using Google.Apis.Drive.v3;
using Google.Apis.Services;

namespace DriveV3Snippets
{
    // Class of demonstrate the use of Drive upload app data. 
    public class UploadAppData
    {
        /// <summary>
        /// Insert a file in the application data folder and prints file Id.
        /// </summary>
        /// <param name="filePath">File path to upload.</param>
        /// <returns>ID's of the inserted files, null otherwise.</returns>
        public static string DriveUploadAppData(string filePath)
        {
            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.DriveAppdata);

                // Create Drive API service.
                var service = new DriveService(new BaseClientService.Initializer
                {
                    HttpClientInitializer = credential,
                    ApplicationName = "Drive API Snippets"
                });
                var fileMetadata = new Google.Apis.Drive.v3.Data.File()
                {
                    Name = "config.json",
                    Parents = new List<string>()
                    {
                        "appDataFolder"
                    }
                };
                FilesResource.CreateMediaUpload request;
                using (var stream = new FileStream(filePath,
                           FileMode.Open))
                {
                    request = service.Files.Create(
                        fileMetadata, stream, "application/json");
                    request.Fields = "id";
                    request.Upload();
                }

                var file = request.ResponseBody;
                // Prints the file id.
                Console.WriteLine("File ID: " + file.Id);
                return file.Id;
            }
            catch (Exception e)
            {
                // TODO(developer) - handle error appropriately
                if (e is AggregateException)
                {
                    Console.WriteLine("Credential Not found");
                }
                else
                {
                    throw;
                }
            }
            return null;
        }
    }
}

Para obtener más información sobre la creación de archivos en carpetas, consulta Crea y propaga carpetas.

Buscar archivos en la carpeta de datos de la aplicación

Para buscar archivos en la carpeta de datos de la aplicación, establece el campo spaces en appDataFolder y usa el método files.list. En la siguiente muestra de código, se indica cómo usar la búsqueda de archivos en la carpeta de datos de la aplicación mediante una biblioteca cliente.

Java

drive/snippets/drive_v3/src/main/java/ListAppData.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.File;
import com.google.api.services.drive.model.FileList;
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 list 10 files in the application data folder.
 */
public class ListAppData {

  /**
   * list down files in the application data folder.
   *
   * @return list of 10 files.
   */
  public static FileList listAppData() 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 = null;
    try {
      credentials = GoogleCredentials.getApplicationDefault()
          .createScoped(Arrays.asList(DriveScopes.DRIVE_APPDATA));
    } catch (IOException e) {
      e.printStackTrace();
    }
    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 {
      FileList files = service.files().list()
          .setSpaces("appDataFolder")
          .setFields("nextPageToken, files(id, name)")
          .setPageSize(10)
          .execute();
      for (File file : files.getFiles()) {
        System.out.printf("Found file: %s (%s)\n",
            file.getName(), file.getId());
      }

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

}

Python

drive/snippets/drive-v3/app_data_snippet/list_appdata.py
from __future__ import print_function

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


def list_appdata():
    """List all files inserted in the application data folder
    prints file titles with Ids.
    Returns : List of items

    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:
        # call drive api client
        service = build('drive', 'v3', credentials=creds)

        # pylint: disable=maybe-no-member
        response = service.files().list(spaces='appDataFolder',
                                        fields='nextPageToken, files(id, '
                                               'name)', pageSize=10).execute()
        for file in response.get('files', []):
            # Process change
            print(F'Found file: {file.get("name")}, {file.get("id")}')

    except HttpError as error:
        print(F'An error occurred: {error}')
        response = None

    return response.get('files')


if __name__ == '__main__':
    list_appdata()

Node.js

drive/snippets/drive_v3/appdata_snippets/list_appdata.js
/**
 * Copyright 2022 Google LLC
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     https://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

/**
 * List all files inserted in the application data folder
 * */
async function listAppdata() {
  // 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.files.list({
      spaces: 'appDataFolder',
      fields: 'nextPageToken, files(id, name)',
      pageSize: 100,
    });
    res.data.files.forEach(function(file) {
      console.log('Found file:', file.name, file.id);
    });
    return res.data.files;
  } catch (err) {
    // TODO(developer) - Handle error
    throw err;
  }
}

module.exports = listAppdata;

PHP

drive/snippets/drive_v3/src/DriveListAppData.php
use Google\Client;
use Google\Service\Drive;
function listAppData()
{
    try {
        $client = new Client();
        $client->useApplicationDefaultCredentials();
        $client->addScope(Drive::DRIVE);
        $driveService = new Drive($client);
        $response = $driveService->files->listFiles(array(
            'spaces' => 'appDataFolder',
            'fields' => 'nextPageToken, files(id, name)',
            'pageSize' => 10
        ));
        foreach ($response->files as $file) {
            printf("Found file: %s (%s)", $file->name, $file->id);
        }
        return $response->files;

    }catch(Exception $e) {
        echo "Error Message: ".$e;
    }

}

.NET

drive/snippets/drive_v3/DriveV3Snippets/ListAppData.cs
using Google.Apis.Auth.OAuth2;
using Google.Apis.Drive.v3;
using Google.Apis.Drive.v3.Data;
using Google.Apis.Services;

namespace DriveV3Snippets
{
    // Class to demonstrate use-case of Drive's list files in the application data folder.
    public class ListAppData
    {
        /// <summary>
        /// List down files in the application data folder.
        /// </summary>
        /// <returns>list of 10 files, null otherwise.</returns>
        public static FileList DriveListAppData()
        {
            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.DriveAppdata);

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

                var request = service.Files.List();
                request.Spaces = "appDataFolder";
                request.Fields = "nextPageToken, files(id, name)";
                request.PageSize = 10;
                var result = request.Execute();
                foreach (var file in result.Files)
                {
                    // Prints the list of 10 file names.
                    Console.WriteLine("Found file: {0} ({1})", file.Name, file.Id);
                }
                return result;
            }
            catch (Exception e)
            {
                // TODO(developer) - handle error appropriately
                if (e is AggregateException)
                {
                    Console.WriteLine("Credential Not found");
                }
                else
                {
                    throw;
                }
            }
            return null;
        }
    }
}

Descarga archivos desde la carpeta de datos de la aplicación

Para descargar un archivo de la carpeta de datos de la aplicación, usa el método files.get. Para obtener más información y ver muestras de código, consulta Cómo descargar el contenido del archivo BLOB.