Rust

Download GMail Message Attachment by ID

See more GMail REST API Examples

Demonstrates how to download a GMail email attachment by the attachment ID. Rust

// This example requires the Chilkat API to have been previously unlocked.
// See Global Unlock Sample for sample code.

let http = chilkat::Http::new();

http.set_auth_token("ACCESS_TOKEN");
http.set_accept("application/json");

// See the following example:  Get GMail Message (format=full)
// It shows how to download an email by message ID, and it shows how to parse the JSON
// response which includes attachment names, ids, and other information.

// This example will assume we already have the attachment id and filename.

// This is the attachment ID for a file named "helloWorld.pdf".
let attachment_id = "ANGjdJ-oy3aCuZISJKLAhUdaEksCEklbAPyMaWzFgqOMGbPCRkgwgeu_Kttd99C17OBTHROkDZGekibTKWXGfscB5ww7fw4E65_V1dQ-jHhb2TD1Cdm58-BbNw2iDxzptco8iILPiSnLLfFn5Ps7nsRcxHaGTt3r0yqFKCuIYNnPK1vM04BXI_cfzo-HnI4I3tD6oHNHOGVQrL01MdShFQjPELPUjXM8z1qs7Kom-QyvV1iOldUN-66UuhynsmDX-CMM5TIdB-8KD_lmdhf-0DqG8JnCA20XpXyfqwS8XFkPA-t-QSjb7SdkHQFtQ4lz2PcBREFzZ2eI5j0l0Y_dQHRPYTeMwkVl1yl4MfFT4C4iso3VSF-eqaIjiFCbXKCFNyeEIW5WFsv189dhlSqU".to_string();

let message_id = "1712bc1dc22da2a2".to_string();

let _ = http.set_url_var("messageId", &message_id);
let _ = http.set_url_var("attachmentId", &attachment_id);

let url = "https://www.googleapis.com/gmail/v1/users/userId/messages/{$messageId}/attachments/{$attachmentId}".to_string();

// When we download, the response is JSON that contains the attachment data base64url encoded, like this:
// {
//  "size": 934,
//  "data": "JVBERi0xLjM ... CiUlRU9GCg=="
// }

let output_file_path = "qa_output/helloWorld.pdf".to_string();

// Download into a StringBuilder.
let sb_json = chilkat::StringBuilder::new();
if http.download_sb(&url, "utf-8", &sb_json).is_err() {
    println!("{}", http.last_error_text());
    return;
}

if http.last_status() != 200 {
    // Something failed.
    // the JSON contains an error message.
    println!("{}", sb_json.get_as_string().unwrap_or_default());
    return;
}

// Load into a Chilkat JSON object.
let json = chilkat::JsonObject::new();
let _ = json.load_sb(&sb_json).is_ok();

// Extract the base64url data into a BinData.
let bd = chilkat::BinData::new();
let _ = json.bytes_of("data", "base64url", &bd).is_ok();

// Save the data to a file.
let _ = bd.write_file("qa_output/helloWorld.pdf").is_ok();

println!("Success.");