Ruby SDK

bundle install
# or
gem install unosend

require 'unosend'

client = Unosend::Client.new(api_key: 'un_your_api_key')

result = client.emails.send(
  from: 'hello@yourdomain.com',
  to: ['user@example.com'],
  subject: 'Hello from Unosend!',
  html: '<h1>Welcome!</h1><p>Thanks for signing up.</p>'
)

puts "Email sent: #{result.id}"

client = Unosend::Client.new(
  api_key: ENV['UNOSEND_API_KEY'],
  base_url: 'https://www.unosend.co/api/v1', # default
  timeout: 30 # seconds
)

result = client.emails.send(
  from: 'John Doe <john@yourdomain.com>',
  to: ['user@example.com'],
  subject: 'Order Confirmation',
  html: '<h1>Order #1234</h1><p>Your order has been confirmed.</p>',
  text: 'Order #1234 - Your order has been confirmed.',
  reply_to: 'support@yourdomain.com',
  cc: ['manager@yourdomain.com'],
  bcc: ['archive@yourdomain.com'],
  tags: [{ name: 'category', value: 'order' }],
  tracking: { open: true, click: true }
)

require 'base64'

pdf_content = Base64.strict_encode64(File.read('invoice.pdf'))

result = client.emails.send(
  from: 'billing@yourdomain.com',
  to: ['customer@example.com'],
  subject: 'Your Invoice',
  html: '<p>Please find your invoice attached.</p>',
  attachments: [
    {
      filename: 'invoice.pdf',
      content: pdf_content,
      content_type: 'application/pdf'
    }
  ]
)

result = client.emails.send(
  from: 'hello@yourdomain.com',
  to: ['user@example.com'],
  subject: 'Welcome, {{first_name}}!',
  template_id: 'tmpl_abc123',
  template_data: {
    first_name: 'Alice',
    company: 'Acme Inc'
  }
)

results = client.emails.send_batch([
  {
    from: 'hello@yourdomain.com',
    to: ['alice@example.com'],
    subject: 'Welcome, Alice!',
    html: '<h1>Welcome!</h1>'
  },
  {
    from: 'hello@yourdomain.com',
    to: ['bob@example.com'],
    subject: 'Welcome, Bob!',
    html: '<h1>Welcome!</h1>'
  }
])

# Get email details
email = client.emails.get('email_abc123')
puts email.status     # 'delivered'
puts email.opened_at  # '2026-02-28T10:30:00Z'

# List emails
emails = client.emails.list(limit: 50, status: 'delivered')
emails.data.each do |email|
  puts "#{email.to} — #{email.status}"
end

# Create domain
domain = client.domains.create(domain: 'yourdomain.com')
puts "DNS records: #{domain.dns_records}"

# Verify after adding DNS records
verified = client.domains.verify(domain.id)
puts "Verified: #{verified.verified}"

# Create audience
audience = client.audiences.create(name: 'Newsletter Subscribers')

# Add contact
contact = client.contacts.create(audience.id,
  email: 'user@example.com',
  first_name: 'Alice',
  last_name: 'Smith',
  metadata: { plan: 'pro' }
)

sms = client.sms.send(
  to: '+14155551234',
  message: 'Your verification code is 384729. Expires in 10 minutes.'
)

puts "SMS sent: #{sms.id} (Cost: $#{sms.cost})"

msg = client.whatsapp.send(
  to: '+919876543210',
  type: 'template',
  template: 'order_update',
  language: 'en',
  variables: ['Alice', 'ORD-1234']
)

begin
  result = client.emails.send(
    from: 'hello@yourdomain.com',
    to: ['user@example.com'],
    subject: 'Hello',
    html: '<h1>Hello</h1>'
  )
  puts "Sent: #{result.id}"
rescue Unosend::AuthenticationError
  puts 'Invalid API key'
rescue Unosend::ValidationError => e
  puts "Validation error: #{e.message}"
rescue Unosend::RateLimitError => e
  puts "Rate limited. Retry after #{e.retry_after} seconds"
rescue Unosend::Error => e
  puts "Error #{e.status_code}: #{e.message}"
end

# config/initializers/unosend.rb
UNOSEND = Unosend::Client.new(api_key: Rails.application.credentials.unosend_api_key)

# app/controllers/emails_controller.rb
class EmailsController < ApplicationController
  def create
    result = UNOSEND.emails.send(
      from: 'welcome@yourdomain.com',
      to: [params[:email]],
      subject: "Welcome, #{params[:name]}!",
      html: "<h1>Welcome, #{params[:name]}!</h1>"
    )
    render json: { id: result.id }
  end
end

require 'sinatra'
require 'unosend'

client = Unosend::Client.new(api_key: ENV['UNOSEND_API_KEY'])

post '/send' do
  data = JSON.parse(request.body.read)
  result = client.emails.send(
    from: 'hello@yourdomain.com',
    to: [data['email']],
    subject: data['subject'],
    html: data['html']
  )
  { id: result.id }.to_json
end