Send GMail using REST API

Demonstrates how to send an email using the GMail REST API.
Chilkat C Downloads

#include <C_CkEmail.h>
#include <C_CkStringBuilder.h>
#include <C_CkJsonObject.h>
#include <C_CkHttp.h>
#include <C_CkHttpResponse.h>

void ChilkatSample(void)
    {
    BOOL success;
    HCkEmail email;
    const char *cid;
    HCkStringBuilder sbHtml;
    int numReplacements;
    HCkStringBuilder sbMime;
    HCkJsonObject json;
    HCkHttp http;
    const char *url;
    HCkHttpResponse resp;

    success = FALSE;

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

    // Use the Chilkat Email API to create or load an email.
    email = CkEmail_Create();

    // The From name/address don't need to be specified. 
    // GMail will automatically use your Gmail address if the following 2 lines are omitted.
    CkEmail_putFromName(email,"My Name");
    CkEmail_putFromAddress(email,"my_account_name@gmail.com");

    CkEmail_AddTo(email,"John Smith","somebody@somewhere.com");
    // To add more recipients, make additional calls to AddTo or AddCC, one per recipient...

    CkEmail_putSubject(email,"This is a test GMail email created using Chilkat.");
    CkEmail_putCharset(email,"utf-8");
    CkEmail_AddPlainTextAlternativeBody(email,"This is a test");

    // Create an HTML email body with an embedded image.
    cid = CkEmail_addRelatedFile(email,"qa_data/jpg/starfish.jpg");
    sbHtml = CkStringBuilder_Create();
    CkStringBuilder_Append(sbHtml,"<html><body>This is a <b>test</b><br><img src=\"cid:STARFISH_CID\"/></body></html>");
    numReplacements = CkStringBuilder_Replace(sbHtml,"STARFISH_CID",cid);

    CkEmail_AddHtmlAlternativeBody(email,CkStringBuilder_getAsString(sbHtml));

    // OK.. we now have an HTML email with an embedded JPG image
    // We'll need to get the full MIME of the email encoded to a base64url string.
    sbMime = CkStringBuilder_Create();
    CkEmail_GetMimeSb(email,sbMime);
    CkStringBuilder_Encode(sbMime,"base64url","utf-8");

    // The body of the HTTP request will be JSON..
    json = CkJsonObject_Create();
    CkJsonObject_UpdateSb(json,"raw",sbMime);

    // Send the email...
    http = CkHttp_Create();
    CkHttp_putAuthToken(http,"GMAIL-ACCESS-TOKEN");

    url = "https://www.googleapis.com/gmail/v1/users/me/messages/send";
    resp = CkHttpResponse_Create();
    success = CkHttp_HttpJson(http,"POST",url,json,"application/json",resp);
    if (success == FALSE) {
        printf("%s\n",CkHttp_lastErrorText(http));
        CkEmail_Dispose(email);
        CkStringBuilder_Dispose(sbHtml);
        CkStringBuilder_Dispose(sbMime);
        CkJsonObject_Dispose(json);
        CkHttp_Dispose(http);
        CkHttpResponse_Dispose(resp);
        return;
    }

    // A status code of 200 indicates success.
    printf("Response status code: %d\n",CkHttpResponse_getStatusCode(resp));
    printf("Response body:\n");
    printf("%s\n",CkHttpResponse_bodyStr(resp));

    // The response body contains JSON.
    // Use the online tool at Generate JSON Parsing Code
    // to generate JSON parsing code.

    // A sample successful JSON response:

    // {
    //  "id": "166f0d4ac39e50bf",
    //  "threadId": "166f0d4ac39e50bf",
    //  "labelIds": [
    //   "SENT"
    //  ]
    // }


    CkEmail_Dispose(email);
    CkStringBuilder_Dispose(sbHtml);
    CkStringBuilder_Dispose(sbMime);
    CkJsonObject_Dispose(json);
    CkHttp_Dispose(http);
    CkHttpResponse_Dispose(resp);

    }