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Unicode C

REST Read Binary Response into BinData Object (Amazon S3)

Demonstrates how to make a REST call that returns a binary response body. This example is valid for files that fit in memory. The example shows how to download a JPG from the Amazon S3 service.

Chilkat Unicode C Downloads

Unicode C
#include <C_CkRestW.h>
#include <C_CkAuthAwsW.h>
#include <C_CkBinDataW.h>

void ChilkatSample(void)
    {
    BOOL success;
    HCkRestW rest;
    BOOL bTls;
    int port;
    BOOL bAutoReconnect;
    HCkAuthAwsW authAws;
    int responseStatusCode;
    const wchar_t *errResponse;
    HCkBinDataW bdBody;

    success = FALSE;

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

    rest = CkRestW_Create();

    //  Connect to the Amazon AWS REST server.
    bTls = TRUE;
    port = 443;
    bAutoReconnect = TRUE;
    success = CkRestW_Connect(rest,L"s3.amazonaws.com",port,bTls,bAutoReconnect);

    //  ----------------------------------------------------------------------------
    //  Important: For buckets created in regions outside us-east-1,
    //  there are three important changes that need to be made.
    //  See Working with S3 Buckets in Non-us-east-1 Regions for the details.
    //  ----------------------------------------------------------------------------

    //  Provide AWS credentials for the REST call.
    authAws = CkAuthAwsW_Create();
    CkAuthAwsW_putAccessKey(authAws,L"AWS_ACCESS_KEY");
    CkAuthAwsW_putSecretKey(authAws,L"AWS_SECRET_KEY");
    CkAuthAwsW_putServiceName(authAws,L"s3");
    success = CkRestW_SetAuthAws(rest,authAws);

    //  Set the bucket name via the HOST header.
    //  In this case, the bucket name is "chilkat100".
    CkRestW_putHost(rest,L"chilkat100.s3.amazonaws.com");

    //  Send the request to download the JPG.
    success = CkRestW_SendReqNoBody(rest,L"GET",L"/starfish.jpg");
    if (success != TRUE) {
        wprintf(L"%s\n",CkRestW_lastErrorText(rest));
        CkRestW_Dispose(rest);
        CkAuthAwsW_Dispose(authAws);
        return;
    }

    //  Read the response header.
    responseStatusCode = CkRestW_ReadResponseHeader(rest);
    if (responseStatusCode < 0) {
        wprintf(L"%s\n",CkRestW_lastErrorText(rest));
        CkRestW_Dispose(rest);
        CkAuthAwsW_Dispose(authAws);
        return;
    }

    wprintf(L"Response status code = %d\n",responseStatusCode);

    //  We expect a 200 response status if the JPG data is coming.
    //  Otherwise, we'll get a string response body with an error message(or no response body).
    if (responseStatusCode != 200) {
        errResponse = CkRestW_readRespBodyString(rest);
        if (CkRestW_getLastMethodSuccess(rest) != TRUE) {
            wprintf(L"%s\n",CkRestW_lastErrorText(rest));
        }
        else {
            wprintf(L"%s\n",errResponse);
        }

        CkRestW_Dispose(rest);
        CkAuthAwsW_Dispose(authAws);
        return;
    }

    bdBody = CkBinDataW_Create();
    success = CkRestW_ReadRespBd(rest,bdBody);
    if (success == FALSE) {
        wprintf(L"%s\n",CkRestW_lastErrorText(rest));
        CkRestW_Dispose(rest);
        CkAuthAwsW_Dispose(authAws);
        CkBinDataW_Dispose(bdBody);
        return;
    }

    //  Save the contents of the response body to a file.
    success = CkBinDataW_WriteFile(bdBody,L"qa_output/starfish.jpg");
    if (success == TRUE) {
        wprintf(L"Success\n");
    }
    else {
        wprintf(L"Failed to write file.\n");
    }



    CkRestW_Dispose(rest);
    CkAuthAwsW_Dispose(authAws);
    CkBinDataW_Dispose(bdBody);

    }