Devsan wiki

Google api calender

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Here’s a step-by-step blog-style guide on creating Google Calendar events in Ruby on Rails using a service account with user impersonation:

🔧 Step-by-Step: Create Google Calendar Events via Rails Console with Service Account

✅ Step 1: Enable Google Calendar API

• Go to Google Cloud Console.

• Create a project (or select an existing one).

• Enable Google Calendar API under APIs & Services > Library.

✅ Step 2: Create a Service Account

• Go to APIs & Services > Credentials.

• Click Create Credentials > Service account.

• Grant it any name, assign “Editor” or appropriate role.

• After creation, click “Add Key” > JSON, and download the key file.

✅ Step 3: Enable Domain-Wide Delegation

• In the service account settings, enable “Domain-wide delegation”.

• Note down the Client ID.

✅ Step 4: Grant Delegation in Google Workspace

(Only if you use a Google Workspace domain)

• Go to admin.google.com > Security > API Controls > Manage domain-wide delegation.

• Add a new API client:

• Client ID: from Step 3

• Scopes: https://www.googleapis.com/auth/calendar

✅ Step 5: Add Gems

In your Rails app, ensure you have these gems in Gemfile:

gem 'googleauth'
gem 'google-apis-calendar_v3'

Then run:

bundle install

✅ Step 6: Authenticate and Impersonate

In Rails console (rails c):

require 'google/apis/calendar_v3'
require 'googleauth'

credential_file = 'path/to/your-service-account.json'

auth = Google::Auth::ServiceAccountCredentials.make_creds(
  json_key_io: File.open(credential_file),
  scope: Google::Apis::CalendarV3::AUTH_CALENDAR
)

auth.sub = "youremail@yourdomain.com"  # user to impersonate
auth.fetch_access_token!

✅ Step 7: Initialize Calendar Service

service = Google::Apis::CalendarV3::CalendarService.new
service.authorization = auth

✅ Step 8: Create and Insert an Event

event = Google::Apis::CalendarV3::Event.new(
  summary: 'Test Event',
  location: 'Online',
  description: 'Testing event creation via Rails console',
  start: { date_time: '2025-04-12T10:00:00+05:30' },
  end: { date_time: '2025-04-12T11:00:00+05:30' },
  attendees: [{ email: 'sandipparida282@gmail.com' }],
  reminders: { use_default: true }
)

calendar_id = 'primary' # or specific calendar ID
service.insert_event(calendar_id, event)

✅ Step 9: 🎉 Done!

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