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C

List Events on a Specified Google Calendar

See more Google Calendar Examples

Demonstrates how to fetch the list of events on a particular Google Calendar. The calendar can be referenced by the calendar ID, or by the keyword "primary".

Chilkat C Downloads

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

void ChilkatSample(void)
    {
    BOOL success;
    HCkJsonObject jsonToken;
    HCkHttp http;
    HCkStringBuilder sbResponse;
    HCkJsonObject json;
    int numEvents;
    int i;

    success = FALSE;

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

    //  This example uses a previously obtained access token having permission for the 
    //  Google Calendar scope.

    //  In this example, Get Google Calendar OAuth2 Access Token, the access
    //  token was saved to a JSON file.  This example fetches the access token from the file..
    jsonToken = CkJsonObject_Create();
    success = CkJsonObject_LoadFile(jsonToken,"qa_data/tokens/googleCalendar.json");
    if (CkJsonObject_HasMember(jsonToken,"access_token") == FALSE) {
        printf("No access token found.\n");
        CkJsonObject_Dispose(jsonToken);
        return;
    }

    http = CkHttp_Create();
    CkHttp_putAuthToken(http,CkJsonObject_stringOf(jsonToken,"access_token"));

    //  Let's get the primary calendar.  A calendar ID could have be used instead of "primary".
    CkHttp_SetUrlVar(http,"calendarId","primary");
    sbResponse = CkStringBuilder_Create();
    success = CkHttp_QuickGetSb(http,"https://www.googleapis.com/calendar/v3/calendars/{$calendarId}/events",sbResponse);
    if (success != TRUE) {
        printf("%s\n",CkHttp_lastErrorText(http));
        CkJsonObject_Dispose(jsonToken);
        CkHttp_Dispose(http);
        CkStringBuilder_Dispose(sbResponse);
        return;
    }

    if (CkHttp_getLastStatus(http) != 200) {
        //  Note: If a 401 unauthorized response is received, it likely means that the OAuth2 access token needs
        //  to be refreshed or re-fetched.
        printf("Error response status: %d\n",CkHttp_getLastStatus(http));
        printf("%s\n",CkStringBuilder_getAsString(sbResponse));
        CkJsonObject_Dispose(jsonToken);
        CkHttp_Dispose(http);
        CkStringBuilder_Dispose(sbResponse);
        return;
    }

    //  A sample JSON response:
    //  (Code for parsing the Google Calendar events is shown below.)

    //  {
    //   "kind": "calendar#events",
    //   "etag": "\"p32cfpufit76da0g\"",
    //   "summary": "support@chilkatcloud.com",
    //   "updated": "2017-08-10T14:00:27.199Z",
    //   "timeZone": "America/Chicago",
    //   "accessRole": "owner",
    //   "defaultReminders": [
    //    {
    //     "method": "popup",
    //     "minutes": 10
    //    }
    //   ],
    //   "nextSyncToken": "CJj8-fLpzNUCEJj8-fLpzNUCGAU=",
    //   "items": [
    //    {
    //     "kind": "calendar#event",
    //     "etag": "\"3004746854620000\"",
    //     "id": "5jt9fopfg3rr9eftegiuq7gc5k",
    //     "status": "confirmed",
    //     "htmlLink": "https://www.google.com/calendar/event?eid=NWp0OWZvcGZnM3JyOWVmdGVnaXVxN2djNWsgc3VwcG9ydEBjaGlsa2F0Y2xvdWQuY29t",
    //     "created": "2017-08-10T13:57:07.000Z",
    //     "updated": "2017-08-10T13:57:07.310Z",
    //     "summary": "Run 10 miles",
    //     "creator": {
    //      "email": "support@chilkatcloud.com",
    //      "self": true
    //     },
    //     "organizer": {
    //      "email": "support@chilkatcloud.com",
    //      "self": true
    //     },
    //     "start": {
    //      "dateTime": "2017-08-10T12:00:00-05:00"
    //     },
    //     "end": {
    //      "dateTime": "2017-08-10T13:00:00-05:00"
    //     },
    //     "iCalUID": "5jt9fopfg3rr9eftegiuq7gc5k@google.com",
    //     "sequence": 0,
    //     "hangoutLink": "https://plus.google.com/hangouts/_/chilkatcloud.com/support?hceid=c3VwcG9ydEBjaGlsa2F0Y2xvdWQuY29t.5jt9fopfg3rr9eftegiuq7gc5k",
    //     "reminders": {
    //      "useDefault": true
    //     }
    //    },
    //    {
    //     "kind": "calendar#event",
    //     "etag": "\"3004746898118000\"",
    //     "id": "7dvh49vd219r3sq7jdueieu8rc",
    //     "status": "confirmed",
    //     "htmlLink": "https://www.google.com/calendar/event?eid=N2R2aDQ5dmQyMTlyM3NxN2pkdWVpZXU4cmMgc3VwcG9ydEBjaGlsa2F0Y2xvdWQuY29t",
    //     "created": "2017-08-10T13:57:29.000Z",
    //     "updated": "2017-08-10T13:57:29.059Z",
    //     "summary": "Eat Giordano's Pizza",
    //     "creator": {
    //      "email": "support@chilkatcloud.com",
    //      "self": true
    //     },
    //     "organizer": {
    //      "email": "support@chilkatcloud.com",
    //      "self": true
    //     },
    //     "start": {
    //      "dateTime": "2017-08-10T15:00:00-05:00"
    //     },
    //     "end": {
    //      "dateTime": "2017-08-10T16:00:00-05:00"
    //     },
    //     "iCalUID": "7dvh49vd219r3sq7jdueieu8rc@google.com",
    //     "sequence": 0,
    //     "hangoutLink": "https://plus.google.com/hangouts/_/chilkatcloud.com/support?hceid=c3VwcG9ydEBjaGlsa2F0Y2xvdWQuY29t.7dvh49vd219r3sq7jdueieu8rc",
    //     "reminders": {
    //      "useDefault": true
    //     }
    //    },
    //    {
    //     "kind": "calendar#event",
    //     "etag": "\"3004746915224000\"",
    //     "id": "5btd89ljn07bg3tlgpimcaqrro",
    //     "status": "confirmed",
    //     "htmlLink": "https://www.google.com/calendar/event?eid=NWJ0ZDg5bGpuMDdiZzN0bGdwaW1jYXFycm8gc3VwcG9ydEBjaGlsa2F0Y2xvdWQuY29t",
    //     "created": "2017-08-10T13:57:37.000Z",
    //     "updated": "2017-08-10T13:57:37.612Z",
    //     "summary": "Nap",
    //     "creator": {
    //      "email": "support@chilkatcloud.com",
    //      "self": true
    //     },
    //     "organizer": {
    //      "email": "support@chilkatcloud.com",
    //      "self": true
    //     },
    //     "start": {
    //      "dateTime": "2017-08-10T16:30:00-05:00"
    //     },
    //     "end": {
    //      "dateTime": "2017-08-10T17:30:00-05:00"
    //     },
    //     "iCalUID": "5btd89ljn07bg3tlgpimcaqrro@google.com",
    //     "sequence": 0,
    //     "hangoutLink": "https://plus.google.com/hangouts/_/chilkatcloud.com/support?hceid=c3VwcG9ydEBjaGlsa2F0Y2xvdWQuY29t.5btd89ljn07bg3tlgpimcaqrro",
    //     "reminders": {
    //      "useDefault": true
    //     }
    //    }
    //   ]
    //  }
    //  

    json = CkJsonObject_Create();
    CkJsonObject_LoadSb(json,sbResponse);

    numEvents = CkJsonObject_SizeOfArray(json,"items");
    i = 0;
    while (i < numEvents) {
        CkJsonObject_putI(json,i);
        printf("%s\n",CkJsonObject_stringOf(json,"items[i].summary"));
        printf("%s\n",CkJsonObject_stringOf(json,"items[i].start.dateTime"));
        printf("%s\n",CkJsonObject_stringOf(json,"items[i].end.dateTime"));
        printf("--\n");
        i = i + 1;
    }

    //  Sample output:

    //  Run 10 miles
    //  2017-08-10T12:00:00-05:00
    //  2017-08-10T13:00:00-05:00
    //  --
    //  Eat Giordano's Pizza
    //  2017-08-10T15:00:00-05:00
    //  2017-08-10T16:00:00-05:00
    //  --
    //  Nap
    //  2017-08-10T16:30:00-05:00
    //  2017-08-10T17:30:00-05:00
    //  --
    //  


    CkJsonObject_Dispose(jsonToken);
    CkHttp_Dispose(http);
    CkStringBuilder_Dispose(sbResponse);
    CkJsonObject_Dispose(json);

    }