(MFC) Google Drive - Resumable Upload

Demonstrates how to do a resumable upload to Google Drive.

For more information, see https://developers.google.com/drive/api/v3/manage-uploads#resumable

Chilkat C/C++ Library Downloads MS Visual C/C++ Libs

See Also: Using MFC CString in Chilkat

#include <CkHttp.h>
#include <CkJsonObject.h>
#include <CkHttpResponse.h>
#include <CkStringBuilder.h>
#include <CkHttpRequest.h>
#include <CkUrl.h>

void ChilkatSample(void)
    {
    CkString strOut;

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

    bool success = true;

    // This example uses a previously obtained access token having permission for the 
    // Google Drive scope. 
    // See Get Google Drive OAuth2 Access Token

    CkHttp http;

    http.put_AuthToken("GOOGLE_DRIVE_ACCESS_TOKEN");

    // First we want to initiate the resumable upload.
    // We send a POST to get a session URI, which will be used to upload the file, and resume if needed.

    // Our POST will look like this:

    // POST https://www.googleapis.com/upload/drive/v3/files?uploadType=resumable HTTP/1.1
    // Authorization: Bearer [YOUR_AUTH_TOKEN]          <-- Chilkat automatically adds this header because the AuthToken property was set.
    // Content-Length: 38                               <-- Chilkat will automatically add this header.
    // Content-Type: application/json; charset=UTF-8    <-- This is the type of this POST, and is specified in the call to PostJson3.
    // X-Upload-Content-Type: application/zip           <-- The type of file we'll be uploading
    // X-Upload-Content-Length: 1366807                 <-- The size of the file we'll be uploading
    // 
    // {
    //   "name": "myObject"
    // }

    http.SetRequestHeader("X-Upload-Content-Type","application/zip");
    http.SetRequestHeader("X-Upload-Content-Length","1366807");

    CkJsonObject json;
    json.UpdateString("name","myZip");

    CkHttpResponse *resp = http.PostJson3("https://www.googleapis.com/upload/drive/v3/files?uploadType=resumable","application/json",json);
    if (http.get_LastMethodSuccess() == false) {
        strOut.append(http.lastErrorText());
        strOut.append("\r\n");
        SetDlgItemText(IDC_EDIT1,strOut.getUnicode());
        return;
    }

    int statusCode = resp->get_StatusCode();
    if (statusCode != 200) {
        strOut.append(resp->bodyStr());
        strOut.append("\r\n");
        strOut.append("response status = ");
        strOut.appendInt(statusCode);
        strOut.append("\r\n");
        SetDlgItemText(IDC_EDIT1,strOut.getUnicode());
        return;
    }

    // The session URI is in the "Location" response header:
    CkStringBuilder sbSessionUri;
    sbSessionUri.Append(resp->getHeaderField("Location"));
    const char *sessionUri = sbSessionUri.getAsString();
    strOut.append("Session URI: ");
    strOut.append(sessionUri);
    strOut.append("\r\n");

    delete resp;

    // Here's a sample session URI:  https://www.googleapis.com/upload/drive/v3/files?uploadType=resumable&upload_id=AEnB2UrszR8lDqlo3mtXJw_0rYI_Hi1oVh1NPFcLfoyBq9NcSjk85kFopoZaVEgT38OSmLl0XsObPf4iCSJwHlrOvvIJQ_ckIQ

    // -----------------------------------------------------------------------------
    // The next step is to upload the file using the session URI:

    // We'll send a PUT that looks like this:

    // PUT https://www.googleapis.com/upload/drive/v3/files?uploadType=resumable&upload_id=xa298sd_sdlkj2 HTTP/1.1
    // Content-Length: 1366807
    // Content-Type: application/zip
    // 
    // [BYTES 0-1366806]

    // First remove the X-Upload-Content-Type and X-Upload-Content-Length request headers we specified earlier, so they don't get sent with subsequent requests.
    http.ClearHeaders();

    // Because the file is likely large, we'll use SynchronousRequest which allows to to pass an HTTP request object where the body can be streamed directly from a file.
    CkHttpRequest req;

    req.put_ContentType("application/zip");
    req.put_HttpVerb("PUT");

    CkUrl url;
    url.ParseUrl(sessionUri);

    req.put_Path(url.pathWithQueryParams());
    strOut.append("Path with Query Param: ");
    strOut.append(url.pathWithQueryParams());
    strOut.append("\r\n");

    // Specify that the request body is to be streamed directly from a file.
    success = req.StreamBodyFromFile("qa_data/zips/big.zip");
    if (success == false) {
        strOut.append(req.lastErrorText());
        strOut.append("\r\n");
        SetDlgItemText(IDC_EDIT1,strOut.getUnicode());
        return;
    }

    resp = http.SynchronousRequest(url.host(),url.get_Port(),url.get_Ssl(),req);
    if (http.get_LastMethodSuccess() == false) {
        strOut.append(http.lastErrorText());
        strOut.append("\r\n");
        SetDlgItemText(IDC_EDIT1,strOut.getUnicode());
        return;
    }

    strOut.append(resp->bodyStr());
    strOut.append("\r\n");
    strOut.append("response status = ");
    strOut.appendInt(statusCode);
    strOut.append("\r\n");

    // Sample output:

    // {
    //  "kind": "drive#file",
    //  "id": "1rx20i53eurtkVQ-RT7Ry8Ct85PgPYMET",
    //  "name": "myZip",
    //  "mimeType": "application/zip"
    // }
    // 
    // response status = 200

    delete resp;


    SetDlgItemText(IDC_EDIT1,strOut.getUnicode());

    }