C
C
Download GMail Message Attachment by ID
See more GMail REST API Examples
Demonstrates how to download a GMail email attachment by the attachment ID.Chilkat C Downloads
#include <C_CkHttp.h>
#include <C_CkStringBuilder.h>
#include <C_CkJsonObject.h>
#include <C_CkBinData.h>
void ChilkatSample(void)
{
BOOL success;
HCkHttp http;
const char *attachmentId;
const char *messageId;
const char *url;
const char *outputFilePath;
HCkStringBuilder sbJson;
HCkJsonObject json;
HCkBinData bd;
success = FALSE;
// This example requires the Chilkat API to have been previously unlocked.
// See Global Unlock Sample for sample code.
http = CkHttp_Create();
CkHttp_putAuthToken(http,"ACCESS_TOKEN");
CkHttp_putAccept(http,"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".
attachmentId = "ANGjdJ-oy3aCuZISJKLAhUdaEksCEklbAPyMaWzFgqOMGbPCRkgwgeu_Kttd99C17OBTHROkDZGekibTKWXGfscB5ww7fw4E65_V1dQ-jHhb2TD1Cdm58-BbNw2iDxzptco8iILPiSnLLfFn5Ps7nsRcxHaGTt3r0yqFKCuIYNnPK1vM04BXI_cfzo-HnI4I3tD6oHNHOGVQrL01MdShFQjPELPUjXM8z1qs7Kom-QyvV1iOldUN-66UuhynsmDX-CMM5TIdB-8KD_lmdhf-0DqG8JnCA20XpXyfqwS8XFkPA-t-QSjb7SdkHQFtQ4lz2PcBREFzZ2eI5j0l0Y_dQHRPYTeMwkVl1yl4MfFT4C4iso3VSF-eqaIjiFCbXKCFNyeEIW5WFsv189dhlSqU";
messageId = "1712bc1dc22da2a2";
CkHttp_SetUrlVar(http,"messageId",messageId);
CkHttp_SetUrlVar(http,"attachmentId",attachmentId);
url = "https://www.googleapis.com/gmail/v1/users/userId/messages/{$messageId}/attachments/{$attachmentId}";
// When we download, the response is JSON that contains the attachment data base64url encoded, like this:
// {
// "size": 934,
// "data": "JVBERi0xLjM ... CiUlRU9GCg=="
// }
outputFilePath = "qa_output/helloWorld.pdf";
// Download into a StringBuilder.
sbJson = CkStringBuilder_Create();
success = CkHttp_DownloadSb(http,url,"utf-8",sbJson);
if (success == FALSE) {
printf("%s\n",CkHttp_lastErrorText(http));
CkHttp_Dispose(http);
CkStringBuilder_Dispose(sbJson);
return;
}
if (CkHttp_getLastStatus(http) != 200) {
// Something failed.
// the JSON contains an error message.
printf("%s\n",CkStringBuilder_getAsString(sbJson));
CkHttp_Dispose(http);
CkStringBuilder_Dispose(sbJson);
return;
}
// Load into a Chilkat JSON object.
json = CkJsonObject_Create();
success = CkJsonObject_LoadSb(json,sbJson);
// Extract the base64url data into a BinData.
bd = CkBinData_Create();
success = CkJsonObject_BytesOf(json,"data","base64url",bd);
// Save the data to a file.
success = CkBinData_WriteFile(bd,"qa_output/helloWorld.pdf");
printf("Success.\n");
CkHttp_Dispose(http);
CkStringBuilder_Dispose(sbJson);
CkJsonObject_Dispose(json);
CkBinData_Dispose(bd);
}