(Tcl) 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 Tcl Extension Downloads Chilkat Tcl Extension Downloads

load ./chilkat.dll

# 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..
set jsonToken [new_CkJsonObject]

set success [CkJsonObject_LoadFile $jsonToken "qa_data/tokens/googleCalendar.json"]
if {[CkJsonObject_HasMember $jsonToken "access_token"] == 0} then {
    puts "No access token found."
    delete_CkJsonObject $jsonToken
    exit
}

set http [new_CkHttp]

CkHttp_put_AuthToken $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"
set sbResponse [new_CkStringBuilder]

set success [CkHttp_QuickGetSb $http "https://www.googleapis.com/calendar/v3/calendars/{$calendarId}/events" $sbResponse]
if {$success != 1} then {
    puts [CkHttp_lastErrorText $http]
    delete_CkJsonObject $jsonToken
    delete_CkHttp $http
    delete_CkStringBuilder $sbResponse
    exit
}

if {[CkHttp_get_LastStatus $http] != 200} then {
    # Note: If a 401 unauthorized response is received, it likely means that the OAuth2 access token needs
    # to be refreshed or re-fetched.
    puts "Error response status: [CkHttp_get_LastStatus $http]"
    puts [CkStringBuilder_getAsString $sbResponse]
    delete_CkJsonObject $jsonToken
    delete_CkHttp $http
    delete_CkStringBuilder $sbResponse
    exit
}

# 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
#    }
#   }
#  ]
# }
# 

set json [new_CkJsonObject]

CkJsonObject_LoadSb $json $sbResponse

set numEvents [CkJsonObject_SizeOfArray $json "items"]
set i 0
while {$i < $numEvents} {
    CkJsonObject_put_I $json $i
    puts [CkJsonObject_stringOf $json {items[i].summary}]
    puts [CkJsonObject_stringOf $json {items[i].start.dateTime}]
    puts [CkJsonObject_stringOf $json {items[i].end.dateTime}]
    puts "--"
    set i [expr $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
# --
# 

delete_CkJsonObject $jsonToken
delete_CkHttp $http
delete_CkStringBuilder $sbResponse
delete_CkJsonObject $json