Sendgrid mailer

sendgrid_delivery.rb

# frozen_string_literal: true
require 'sendgrid-ruby'
require 'sendgrid_mailer/mailer'

class SendgridDelivery
  class InvalidEmail < StandardError; end

  def initialize(*)
  end

  def api
    unless api_key = ENV['SENDGRID_API_KEY']
      raise 'Sendgrid api key is not present. Emails cannot be delivered '
    end
    SendGrid::API.new(api_key: api_key)
  end

  def deliver!(mail)
    email = SendGrid::Mail.new
    email.from =
      SendGrid::Email.new(email: mail[:from].value,
                          name: mail[:from_name]&.value)
    email.subject = mail[:subject]&.value

    if mail['template-id']
      email.template_id = mail['template-id'].value
    elsif mail.body
      email.add_content(SendGrid::Content.new(type: mail.mime_type,
                                              value: mail.body.decoded))
    end

    personalization = SendGrid::Personalization.new
    personalization.add_to(SendGrid::Email.new(email: mail[:to].value,
                                               name: mail[:to_name]&.value))

    if bccs = mail[:bcc]&.value
      Array(bccs).each do |bcc|
        personalization.add_bcc(SendGrid::Email.new(email: bcc))
      end
    end

    if subs = mail.sendgrid_substitutions
      subs.each do |key, value|
        personalization.add_substitution(
          SendGrid::Substitution.new(key: key.to_s, value: value.to_s)
        )
      end
    end

    if categories = mail.sendgrid_categories
      categories.each do |name|
        email.add_category(SendGrid::Category.new(name: name))
      end
    end

    email.add_personalization(personalization)

    mail.attachments.each do |item|
      attachment = SendGrid::Attachment.new
      attachment.content = Base64.strict_encode64(item.decoded)
      attachment.type = item.mime_type
      attachment.filename = item.filename
      attachment.disposition = 'attachment'
      email.add_attachment(attachment)
    end

    Rails.logger.debug('Sending email using SendGrid API:')
    Rails.logger.debug(email.to_json)
    response = api.client.mail._('send').post(request_body: email.to_json)

    Rails.logger.debug("Response code: #{response.status_code}\nResponse body: #{response.body}")

    unless (200..299).include?(Integer(response.status_code))
      raise InvalidEmail,
            "Bad email. Response body: #{response.body}. Input was: #{email.to_json}"
    end
  end
end