A demo of calling Google Calendar API

google_calendar_demo.R

library(googleAuthR)

## set scopes for calendar
options(googleAuthR.scopes.selected = "https://www.googleapis.com/auth/calendar.readonly",
        googleAuthR.client_id = "XXXX",  ## add your Google project client Id - find it at https://console.developers.google.com/apis/credentials then click on the appropriate OAuth 2.0 client ID
        googleAuthR.client_secret = "XXXX")  ## add your Google project client secret - at same place as above

## make sure calendar API is activated for your Google Project at below URL:
# https://console.cloud.google.com/apis/api/calendar-json.googleapis.com/overview


## this is taken and simplified from 
# https://github.com/MarkEdmondson1234/autoGoogleAPI/blob/master/googlecalendarv3.auto/R/calendar_functions.R#L962

#' Gets a list of events for calendarId
#' 
#' @param calendarId The calendar to get.  Default is primary for authenticated user
#' @return a big list of JSON
events.list <- function(calendarId = "primary") {
  url <- sprintf("https://www.googleapis.com/calendar/v3/calendars/%s/events", 
                 calendarId)

  f <- googleAuthR::gar_api_generator(url, "GET", 
                                      data_parse_function = function(x) x)
  f()
  
}

## ---------
# To use:

## authenticate with email that has access to the calendar
gar_auth()

## should kick you out to Google OAuth2 flow.  Come back here when done....

## get default (primary) calendar list
events <- events.list()

## events is raw JSON response, 
## parse down to items by modifying the data_parse_function in events.list()
## or operating afterwards in code like below
events$items$summary