I’m sending (plain text) emails containing urls to a web site. They look like:

https://www.example.com/account/confirm/?place_id=ChIJA5Vy7Qfp2UcRpbHr9bNg4Tw

(The place_id parameter is a Place ID from the Google Maps API)

But my server logs show entries like

GET /account/confirm/?place_id=DuVWjMw28Eld43dEZhEcXEDcJfd

This only happens sometimes, I have plenty of entries that look as expected:

GET /account/confirm/?place_id=ChIJA5Vy7Qfp2UcRpbHr9bNg4Tw

And if I send test emails to myself, I get the correct URLs

Does anyone know what might be happening: how are these parameters getting mangled?. I’m using the following ruby code, running on AWS Lambda. The code connects via SMTP to a Gmail account:

require 'json'
require 'mail'
require 'securerandom'

def lambda_handler(event:, context:)
  eventBody = JSON.parse(event["body"])

  smtp = eventBody['smtp']
  Mail.defaults do
    delivery_method :smtp, {
        address: smtp['address'],
        port: smtp['port'],
        user_name: smtp['username'],
        password: smtp['password'],
        authentication: smtp['authentication'],
        enable_starttls_auto: smtp['enable_starttls_auto']
      }
  end

  mailConfig = eventBody['mail']
  mail = Mail.new do
    message_id      "<#{SecureRandom.uuid.upcase}@#{mailConfig['from']['address'].split('@').last}>"
    to              mailConfig['to']
    from            "#{mailConfig['from']['name']} <#{mailConfig['from']['address']}>"
    subject         mailConfig['subject']

    unless mailConfig['body'].nil?
      body          mailConfig['body']
    end
  end

  unless mailConfig['body_text'].nil?
    mail.text_part = Mail::Part.new do
      body          mailConfig['body_text']
    end
  end

  unless mailConfig['body_html'].nil?
    mail.html_part = Mail::Part.new do
      content_type  'text/html; charset=UTF-8'
      body          mailConfig['body_html']
    end
  end

  unless mailConfig['headers'].nil?
    mailConfig['headers'].each do |name, value|
      mail.header[name] = value
    end
  end

  {
    statusCode: 201,
    body: JSON.generate({
      # event: event,
      # body: eventBody,
      # context: context,
      mail: mail.to_s
    })
}