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C

BatchModify - Add a Label to each Message in Search Results

See more GMail REST API Examples

Searchs GMail for messages meeting a criteria and adds a label to each message found.

Chilkat C Downloads

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

void ChilkatSample(void)
    {
    BOOL success;
    HCkHttp http;
    const char *userId;
    const char *query;
    const char *url;
    HCkStringBuilder sb;
    HCkJsonObject json;
    HCkJsonObject json2;
    int i;
    int numMessages;
    const char *id;
    const char *labelId;
    HCkHttpResponse resp;

    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,"GMAIL-ACCESS-TOKEN");

    userId = "me";
    CkHttp_SetUrlVar(http,"userId",userId);

    query = "subject:questions";
    CkHttp_SetUrlVar(http,"query",query);

    url = "https://www.googleapis.com/gmail/v1/users/{$userId}/messages?q={$query}";

    sb = CkStringBuilder_Create();
    success = CkHttp_QuickGetSb(http,url,sb);
    if (success == FALSE) {
        printf("%s\n",CkHttp_lastErrorText(http));
        CkHttp_Dispose(http);
        CkStringBuilder_Dispose(sb);
        return;
    }

    json = CkJsonObject_Create();
    CkJsonObject_LoadSb(json,sb);
    CkJsonObject_putEmitCompact(json,FALSE);
    printf("%s\n",CkJsonObject_emit(json));

    if (CkHttp_getLastStatus(http) != 200) {
        printf("Failed.\n");
        CkHttp_Dispose(http);
        CkStringBuilder_Dispose(sb);
        CkJsonObject_Dispose(json);
        return;
    }

    // If successful, the received JSON looks like this:
    // {
    //   "messages": [
    //     {
    //       "id": "166f583051d36144",
    //       "threadId": "166f583051d36144"
    //     },
    //     {
    //       "id": "166f5815e1f36144",
    //       "threadId": "166f5815e1f36144"
    //     },
    // 	...
    //     {
    //       "id": "166f580639e36144",
    //       "threadId": "166f580639e36144"
    //     },
    //     {
    //       "id": "15dbc2e28ec789c6",
    //       "threadId": "15dbc2e28ec789c6"
    //     }
    //   ],
    //   "nextPageToken": "13434766102274844688",
    //   "resultSizeEstimate": 103
    // }
    // 

    // Next, we'll be sending an HTTP POST to add the label "questions" to each message in the
    // search results.  The JSON to be sent for the batchModify is this:

    // 	{
    // 	  "ids": [
    // 	    string
    // 	  ],
    // 	  "addLabelIds": [
    // 	    string
    // 	  ],
    // 	  "removeLabelIds": [
    // 	    string
    // 	  ]
    // 	}

    // We'll omit "removeLabelIds" because we're not removing any labels.
    // We are parsing the JSON search results, and at the same time building the batchModify JSON.

    json2 = CkJsonObject_Create();

    i = 0;
    numMessages = CkJsonObject_SizeOfArray(json,"messages");
    while ((i < numMessages)) {
        CkJsonObject_putI(json,i);
        id = CkJsonObject_stringOf(json,"messages[i].id");
        CkJsonObject_putI(json2,i);
        CkJsonObject_UpdateString(json2,"ids[i]",id);
        i = i + 1;
    }

    // We need the id of the label (not the name).
    // I know the name of the label is "questions", but I need to know the id.
    // See this example: Get Label Id by Name
    // The id of my label named "questions" is "Label_43"
    labelId = "Label_43";
    CkJsonObject_UpdateString(json2,"addLabelIds[0]",labelId);
    CkJsonObject_UpdateNewArray(json2,"removeLabelIds");

    CkJsonObject_putEmitCompact(json2,FALSE);
    printf("%s\n",CkJsonObject_emit(json2));

    // Send the batchModify
    url = "https://www.googleapis.com/gmail/v1/users/{$userId}/messages/batchModify";
    resp = CkHttpResponse_Create();
    success = CkHttp_HttpJson(http,"POST",url,json2,"application/json",resp);
    if (success == FALSE) {
        printf("%s\n",CkHttp_lastErrorText(http));
        CkHttp_Dispose(http);
        CkStringBuilder_Dispose(sb);
        CkJsonObject_Dispose(json);
        CkJsonObject_Dispose(json2);
        CkHttpResponse_Dispose(resp);
        return;
    }

    printf("status = %d\n",CkHttpResponse_getStatusCode(resp));

    // A 204 response status indicate success.
    if (CkHttpResponse_getStatusCode(resp) != 204) {
        printf("%s\n",CkHttpResponse_bodyStr(resp));
        printf("Failed.\n");
        CkHttp_Dispose(http);
        CkStringBuilder_Dispose(sb);
        CkJsonObject_Dispose(json);
        CkJsonObject_Dispose(json2);
        CkHttpResponse_Dispose(resp);
        return;
    }

    // The 204 response has an empty response body..

    printf("BatchModify success!\n");


    CkHttp_Dispose(http);
    CkStringBuilder_Dispose(sb);
    CkJsonObject_Dispose(json);
    CkJsonObject_Dispose(json2);
    CkHttpResponse_Dispose(resp);

    }