C++ Google Drive: Download a File (Stream to the Filesystem)

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Downloads the content of a file by ID. (In this example the file id = 1R_70heIyzIAu1_u0prXbYcaIiJRVkgBl) The file is streamed directly to the filesystem. Note: The alt=media query param must be used to download the file content (as opposed to the file metadata).

Documentation: https://developers.google.com/drive/v3/reference/files/get

#include <CkRest.h>
#include <CkOAuth2.h>
#include <CkStringBuilder.h>
#include <CkStream.h>

void ChilkatSample(void)
    {
    CkRest rest;
    bool success;

    //   Provide a previously obtained OAuth2 access token.
    CkOAuth2 oauth2;
    oauth2.put_AccessToken("OAUTH2_ACCESS_TOKEN");
    rest.SetAuthOAuth2(oauth2);

    success = rest.Connect("www.googleapis.com",443,true,true);
    if (success != true) {
        std::cout << rest.lastErrorText() << "\r\n";
        return;
    }

    rest.AddQueryParam("includeTeamDriveItems","true");
    rest.AddQueryParam("supportsTeamDrives","true");
    rest.AddQueryParam("alt","media");

    //  First send the HTTP request.
    success = rest.SendReqNoBody("GET","/drive/v3/files/1R_70heIyzIAu1_u0prXbYcaIiJRVkgBl");
    if (success != true) {
        std::cout << rest.lastErrorText() << "\r\n";
        return;
    }

    //  Read the response header.  If the response status code is success, stream to the file.
    //  Otherwise receive the error response text.
    int statusCode = rest.ReadResponseHeader();
    if (statusCode < 0) {
        std::cout << rest.lastErrorText() << "\r\n";
        return;
    }

    if (statusCode != 200) {
        std::cout << "Received error response code: " << statusCode << "\r\n";
        //  Read the error response body.
        CkStringBuilder sbErrResponse;
        success = rest.ReadRespSb(sbErrResponse);
        if (success != true) {
            std::cout << rest.lastErrorText() << "\r\n";
            return;
        }

        std::cout << "Error response:" << sbErrResponse.getAsString() << "\r\n";
        return;
    }

    //  Stream the response body to the output file.
    CkStream respBodyStream;
    respBodyStream.put_SinkFile("/someDirectory/penguins.jpg");
    success = rest.ReadRespBodyStream(respBodyStream,true);
    if (success != true) {
        std::cout << rest.lastErrorText() << "\r\n";
        return;
    }

    std::cout << "Example Completed." << "\r\n";
    }