Quolle Ruby SDK

Official Ruby client for the Quolle email API.

Install

gem install quolle

Or in your Gemfile:

gem "quolle"

Requires Ruby 2.7+. No third-party dependencies.

Quick start

require "quolle"

quolle = Quolle.new(api_key: "qle_...") # or set QUOLLE_API_KEY

result = quolle.emails.send(
  from: "hello@mail.yourdomain.com",
  to: "customer@example.com",
  subject: "Welcome!",
  html: "<h1>Thanks for signing up</h1>"
)

puts "Queued: #{result['id']}"

Sending

Multiple recipients

quolle.emails.send(
  from: "hello@mail.yourdomain.com",
  to: ["a@example.com", "b@example.com"],
  subject: "Announcement",
  html: "<p>Hello everyone</p>"
)

Templates

quolle.emails.send(
  from: "hello@mail.yourdomain.com",
  to: "customer@example.com",
  template: "welcome-email",
  variables: { firstName: "Amaka", planName: "Starter" }
)

Scheduled send

quolle.emails.send(
  from: "hello@mail.yourdomain.com",
  to: "customer@example.com",
  subject: "Your weekly digest",
  html: "<p>Here's what happened this week.</p>",
  scheduled_at: "2026-12-25T09:00:00.000Z"
)

Idempotency

quolle.emails.send(
  from: "billing@mail.yourdomain.com",
  to: "customer@example.com",
  subject: "Invoice #1234",
  html: "<p>Your invoice is attached.</p>",
  idempotency_key: "order_invoice_12345"
)

Batch

Up to 100 emails in one all-or-nothing request:

result = quolle.emails.send_batch([
  { from: "hello@mail.yourdomain.com", to: "a@example.com", subject: "Hi Alice", html: "<p>Hi Alice</p>" },
  { from: "hello@mail.yourdomain.com", to: "b@example.com", subject: "Hi Bob", html: "<p>Hi Bob</p>" }
])
puts "Queued #{result['queued']}"

Attachments

Pass attachments: — an array of hashes with filename, base64 content, and an optional contentType. Up to 20 files, 10 MB total.

require "base64"

quolle.emails.send(
  from: "billing@mail.yourdomain.com",
  to: "customer@example.com",
  subject: "Your invoice",
  html: "<p>Invoice attached.</p>",
  attachments: [
    {
      filename: "invoice.pdf",
      content: Base64.strict_encode64(File.binread("invoice.pdf")),
      contentType: "application/pdf"
    }
  ]
)

Retrieve & cancel

email = quolle.emails.get("a1b2c3d4-...")
puts email["status"] # queued | sending | sent | delivered | bounced | failed

quolle.emails.cancel("a1b2c3d4-...") # only while status == "scheduled"

Error handling

begin
  quolle.emails.send(
    from: "hello@mail.yourdomain.com", to: "customer@example.com",
    subject: "Welcome!", html: "<h1>Welcome</h1>"
  )
rescue Quolle::Error => e
  puts e.status_code # e.g. 402
  puts e.message     # e.g. "Monthly limit reached"
  puts e.data        # extra fields, e.g. {"limit" => 3000}
end

Testing your integration

Send to a reserved test address to simulate any outcome without touching your sending reputation: delivered@test.quolle.com, bounced@test.quolle.com, complained@test.quolle.com, suppressed@test.quolle.com.

Verifying webhooks

Confirm an incoming webhook really came from Quolle. Pass the raw request body, the Quolle-Signature header, and your signing secret (whsec_…):

begin
  event = quolle.webhooks.verify(
    request.body.read,                  # raw body
    request.env["HTTP_QUOLLE_SIGNATURE"],
    "whsec_your_signing_secret"
  )
  # event["event"] == "email.delivered"
rescue Quolle::Error
  halt 400
end

HMAC-SHA256 with a 5-minute timestamp window (replay protection).

Automatic retries

Transient failures — HTTP 429 (rate limit) and 5xx, plus network errors — are retried automatically with exponential backoff, honoring the Retry-After header. To avoid double-sending, a POST is only retried on a 5xx/network error when you pass an idempotency key; a 429 is always safe to retry (the request was never processed). Tune with max_retries: on Quolle.new (default 3).

License

MIT

quolle

Development