Lib.rs

Google Drive Client (Rocket)

This library provide a way to connect to google drive API (v3) using a service account. You can make basic operations like upload, list, or download files. This code is meant to be used with Rocket server since we can use the service account to provide access to drive without user interaction. For other use you have another libraries like gooogle-drive3 among others.

Dependencies

• Rocket

In your project you need to import these dependencies:

# Rocket Webserver
[dependencies.google_drive_client]
version = "0.4.6"

How to use it

You have a provider that you can get to use directly like this example:

use google_drive_client::{GoogleDriveClient, DriveFileList, DriveFileSearchBuilder};

let gdrive_client: GoogleDriveClient = GoogleDriveClient::default();
let result = gdrive_client.find(DriveFileSearchBuilder::build()
        .with_order_by("name")
        .done());
let file_list:DriveFileList = result.unwrap();

In this example you can see how we can get a list of files ordered by name on our drive.

Another example is using rocket, you can manage the client with rocket:

let gdrive_client: GoogleDriveClient = GoogleDriveClient::default();
rocket.manage(gdrive_client);

Then you can use it in a controller like this:

#[get("/storage/download_file/<file_id>")]
fn download_file(gdrive: State<GoogleDriveClient>, file_id: String) -> FileDownloadResponse {
    let storage = gdrive.inner().clone();
    storage.download_file(&file_id).unwrap()
}

In the last example we use FileDownloadResponse, that type implements Responder from rocket, so you can just use it directly to put the file content in the response directly, it's a clean way to resolve the response of files.

Setup Service Account

To use this library you need a service account from google, when you have that service account you will get a json format service account, that contains all the private information to authenticate with gdrive. This library scan some locations to get that file, first it checks an environment variable called GDRIVE_ACCOUNT_FILE_NAME if that variable is present it should contain the full path location to the json file, if this variable is not present the library continue scanning in the home directory, a service account json file with name service_account.json should be there. If none of these options are available the library will throw an error.

Setup share account

Since service accounts are not allowed to own files directly because are not real accounts we need to share the files created with this account to the real account to be able to see the files in the real account drive. To do this we share files with the real account, to do that we use an environment variable to set that account, that variable is called GDRIVE_SHARE_ACCOUNT all files and folders created are going to be shared with this account. If this variable is not set the files are going to be created but not shared so you will not see them in the gdrive account but the files are going to be there.

Multiple chunk uploads support

Now you can upload files using the multiple chunks logic provided by google. Basically you need to provide a chunk size in the configuration of the client. You can do that like this:

use google_drive_client::{GoogleDriveClient, DriveFileList, DriveFileSearchBuilder, GoogleDriveClientParams};

let gdrive_client: GoogleDriveClient = GoogleDriveClient::new(GoogleDriveClientParams {
                                          request_timeout: Duration::from_secs(30),
                                          chunk_size: Some(ChunkSize::new(10, ChunkSizeUnitType::MB)),
                                          proxy: None
                                      });

In the example you have a chunk size of 10MB so if you have a file of 20MB the file will be uploaded in 2 chunks of 10MB.

Proxy support

You can configure a proxy on the client by specifying the proxy in the parameters like this:

use google_drive_client::{GoogleDriveClient, DriveFileList, DriveFileSearchBuilder, GoogleDriveClientParams};

let gdrive_client: GoogleDriveClient = GoogleDriveClient::new(GoogleDriveClientParams {
                                          request_timeout: Duration::from_secs(30),
                                          chunk_size: Some(ChunkSize::new(10, ChunkSizeUnitType::MB)),
                                          proxy: Some("http://localhost:8888".to_string())
                                      });