(MFC) Google Drive - Upload File

This example demonstrates how to upload a file to Google Drive. The assumption is that the file can be loaded into memory and uploaded. It is also possible to stream large files to Google Drive, but the code required is a little more complex.

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

See Also: Using MFC CString in Chilkat

#include <CkAuthGoogle.h>
#include <CkRest.h>
#include <CkJsonObject.h>
#include <CkJsonArray.h>
#include <CkBinData.h>

void ChilkatSample(void)
    {
    CkString strOut;

    bool success = true;

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

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

    CkAuthGoogle gAuth;
    gAuth.put_AccessToken("GOOGLE_DRIVE_ACCESS_TOKEN");

    CkRest rest;

    // Connect using TLS.
    bool bAutoReconnect = true;
    success = rest.Connect("www.googleapis.com",443,true,bAutoReconnect);

    // Provide the authentication credentials (i.e. the access token)
    rest.SetAuthGoogle(gAuth);

    // -------------------------------------------------------------------------
    // A multipart upload to Google Drive needs a multipart/related Content-Type
    rest.AddHeader("Content-Type","multipart/related");

    // Specify each part of the request.

    // The 1st part is JSON with information about the file.
    rest.put_PartSelector("1");
    rest.AddHeader("Content-Type","application/json; charset=UTF-8");

    // Construct the JSON that will contain the metadata about the file data to be uploaded...
    CkJsonObject json;
    json.AppendString("name","starfish.jpg");
    json.AppendString("description","A picture of a starfish.");
    json.AppendString("mimeType","image/jpeg");

    // To place the file in a folder, we must add a parents[] array to the JSON
    // and add the folder ID.  
    // In a previous example (see Lookup Google Drive Folder ID
    // we showed how to find the folder ID for a folder in Google Drive.

    // Use the folder ID we already looked up..
    const char *folderId = "1Fksv-TfA1ILii1YjXsNa1-rDu8Cdrg72";
    CkJsonArray *parents = json.AppendArray("parents");
    parents->AddStringAt(-1,folderId);
    delete parents;

    rest.SetMultipartBodyString(json.emit());

    // The 2nd part is the file content, which will contain the binary image data.
    rest.put_PartSelector("2");
    rest.AddHeader("Content-Type","image/jpeg");

    CkBinData jpgBytes;
    success = jpgBytes.LoadFile("qa_data/jpg/starfish.jpg");

    // Add the data to our upload
    rest.SetMultipartBodyBd(jpgBytes);

    const char *jsonResponse = rest.fullRequestMultipart("POST","/upload/drive/v3/files?uploadType=multipart");
    if (rest.get_LastMethodSuccess() != true) {
        strOut.append(rest.lastErrorText());
        strOut.append("\r\n");
        SetDlgItemText(IDC_EDIT1,strOut.getUnicode());
        return;
    }

    // A successful response will have a status code equal to 200.
    if (rest.get_ResponseStatusCode() != 200) {
        strOut.append("response status code = ");
        strOut.appendInt(rest.get_ResponseStatusCode());
        strOut.append("\r\n");
        strOut.append("response status text = ");
        strOut.append(rest.responseStatusText());
        strOut.append("\r\n");
        strOut.append("response header: ");
        strOut.append(rest.responseHeader());
        strOut.append("\r\n");
        strOut.append("response JSON: ");
        strOut.append(jsonResponse);
        strOut.append("\r\n");
        SetDlgItemText(IDC_EDIT1,strOut.getUnicode());
        return;
    }

    json.Load(jsonResponse);

    // Show the full JSON response.
    json.put_EmitCompact(false);
    strOut.append(json.emit());
    strOut.append("\r\n");

    // A successful response looks like this:
    // {
    //   "kind": "drive#file",
    //   "id": "0B53Q6OSTWYoldmJ0Z3ZqT2x5MFk",
    //   "name": "starfish.jpg",
    //   "mimeType": "image/jpeg"
    // }

    // Get the fileId:
    strOut.append("fileId: ");
    strOut.append(json.stringOf("id"));
    strOut.append("\r\n");


    SetDlgItemText(IDC_EDIT1,strOut.getUnicode());

    }