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Archivia dati specifici dell'applicazione

La cartella di dati delle applicazioni è una cartella speciale nascosta che l'app può utilizzare per archiviare dati specifici dell'applicazione, ad esempio i file di configurazione. La cartella di dati dell'applicazione viene creata automaticamente quando tenti di creare un file al suo interno. Utilizza questa cartella per archiviare i file con cui l'utente non deve interagire direttamente. Questa cartella è accessibile solo dalla tua applicazione e i suoi contenuti sono nascosti all'utente e alle altre applicazioni di Drive.

I file in appDataFolder non possono essere spostati da una posizione di archiviazione all'altra (spazi). Per ulteriori informazioni, consulta Organizzazione dei file.

La cartella dei dati dell'applicazione viene eliminata quando un utente disinstalla la tua app dal proprio Drive. Gli utenti possono anche eliminare manualmente la cartella di dati dell'app.

Ambito della cartella dei dati dell'applicazione

Prima di poter accedere alla cartella dei dati dell'applicazione, devi richiedere l'accesso all'ambito https://www.googleapis.com/auth/drive.appdata. Per ulteriori informazioni sugli ambiti e su come richiederne l'accesso, consulta l'articolo Informazioni su autorizzazione e autenticazione specifiche dell'API. Per ulteriori informazioni su ambiti OAuth 2.0 specifici, consulta Ambiti OAuth 2.0 per API di Google.

Crea un file nella cartella dei dati dell'applicazione

Per creare un file nella cartella dei dati dell'applicazione, specifica appDataFolder nella proprietà parents del file e utilizza il metodo files.create per caricarlo nella cartella. Il seguente esempio di codice mostra come inserire un file in una cartella utilizzando una libreria client.

Java

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

Visualizza su GitHub

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

Visualizza su GitHub

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

Visualizza su GitHub

/**
 * 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

Visualizza su GitHub

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

Visualizza su GitHub

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;
        }
    }
}

Per ulteriori informazioni sulla creazione di file nelle cartelle, vedi Creare e compilare cartelle.

Cercare file nella cartella dei dati dell'applicazione

Per cercare i file nella cartella dei dati dell'applicazione, imposta il campo spaces su appDataFolder e usa il metodo files.list. Il seguente esempio di codice mostra come utilizzare la ricerca di file nella cartella di dati dell'applicazione utilizzando una libreria client.

Java

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

Visualizza su GitHub

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

Visualizza su GitHub

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

Visualizza su GitHub

/**
 * 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

Visualizza su GitHub

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

Visualizza su GitHub

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;
        }
    }
}

Scarica i file dalla cartella dei dati dell'applicazione

Per scaricare un file dalla cartella dei dati dell'applicazione, utilizza il metodo files.get. Per ulteriori informazioni e per visualizzare gli esempi di codice, vai a Scaricare il contenuto del file blob.