A quick wrapper for TDD'ing through Lambda

readme.md

DocMill Lambda

Lambda function to send SES received emails to DocMill API.

Tips and deployment notes

Adding a new library?

Make sure it's included in ./vendor:

bundle install --path vendor/bundle

Uploading to s3?

Zip up the app and use AWS CLI (or whatever you want) to send it to s3:

zip -r function.zip function.rb vendor
aws s3 mv function.zip s3://your-s3-url

function.rb

require 'aws-sdk-core'
require 'aws-sdk'
require 'httparty'
require 'json'
require 'logger'
require 'mail'

def lambda_handler(event:, context:)
  logger = Logger.new($stdout)
  message = JSON.parse(event['Records'][0]['Sns']['Message'])

  bucket_name = message['receipt']['action']['bucketName']
  object_key = message['receipt']['action']['objectKey']
  # eg: arn:aws:sns:us-east-1:104720634813:SESS3Upload
  region = message['receipt']['action']['topicArn'].split(':')[3]

  s3 = Aws::S3::Client.new(region: region)
  s3_object = s3.get_object(bucket: bucket_name, key: object_key)

  logger.info

  temp_email = Tempfile.new('email.eml')
  temp_email.write(s3_object.body.read)

  email = Mail.read(temp_email.path)

  email_attachments = email.attachments.map do |attachment|
    temp = Tempfile.new(attachment.filename)
    temp.write(attachment.body)
    temp
  end

  options = {
    body: {
      external_document: {
        document_type: 'invoice',
        raw_email: File.open(temp_email.path),
        attachments: email_attachments.map do |attachment_file|
          File.open(attachment_file.path)
        end,
        metadata: {
          from: email.from,
          message_id: email.message_id,
          reply_to: email.reply_to,
          return_path: email.return_path,
          sent_date: email.date.to_s,
          subject: email.subject,
          to: email.to
        }
      }
    },
    headers: {
      "access-token" => "gFf0cBHiL5WuKqAEelL1GA",
      "token-type" => "Bearer",
      "client" => "tEn-yRFIUgOJgyxFC9DpzA",
      "expiry" => "1583301738",
      "uid" => "[email protected]"
    }
  }

  api_request = HTTParty.post(
    'https://ancient-beach-66221.herokuapp.com/api/v1/external_documents',
    options
  )

  if api_request.success?
    {
      body: JSON.generate('Successfully sent to DocMill'),
      statusCode: 201
    }
  else
    {
      body: JSON.generate(
        "DocMill failed to receive the request, received #{api_request.code}"
      ),
      statusCode: 500
    }
  end
end

function_spec.rb

require 'spec_helper'

require 'aws-sdk'
require 'json'
require 'httparty'

require './function.rb'

RSpec.describe 'lambda_handler' do
  before do
    expect_any_instance_of(Aws::S3::Client).to receive(:get_object)
      .and_return(
        OpenStruct.new(
          body: OpenStruct.new(
            read: File.read('./spec/fixtures/sample-email.eml')
          )
        )
      )
  end

  subject! do
    lambda_handler(
      event: JSON.parse(File.read('./spec/fixtures/s3-example-event.json')),
      context: nil
    )
  end

  context 'successfully sends to DocMill' do
    before do
      expect(HTTParty).to receive(:post)
      .and_return(
        OpenStruct.new(
          success?: true
        )
      )
    end

    it do
      is_expected.to eq(
        body: JSON.generate('Successfully sent to DocMil'),
        statusCode: 201
      )
    end
  end

  context 'unsuccessfully sends to DocMill' do
    before do
      expect(HTTParty).to receive(:post)
      .and_return(
        OpenStruct.new(
          code: 500,
          success?: false
        )
      )
    end

    it do
      is_expected.to eq(
        body: JSON.generate('DocMill failed to receive the request, received 500'),
        statusCode: 500
      )
    end
  end
end

s3-example-event.json

{
  "Records": [
      {
          "EventSource": "aws:sns",
          "EventVersion": "1.0",
          "EventSubscriptionArn": "arn:aws:sns:us-east-1:104720634813:SESS3Upload:aab9a0d2-79bc-4140-9bdb-c2029a22b0bb",
          "Sns": {
              "Type": "Notification",
              "MessageId": "bd77840f-4a8d-5adb-96f4-d2c75791e472",
              "TopicArn": "arn:aws:sns:us-east-1:104720634813:SESS3Upload",
              "Subject": "Amazon SES Email Receipt Notification",
              "Message": "{\"notificationType\":\"Received\",\"mail\":{\"timestamp\":\"2020-02-20T05:36:27.448Z\",\"source\":\"[email protected]\",\"messageId\":\"a4ihukv3og9kbpb321fffe1kr0snb6q8m765so01\",\"destination\":[\"[email protected]\"],\"headersTruncated\":false,\"headers\":[{\"name\":\"Return-Path\",\"value\":\"<[email protected]>\"},{\"name\":\"Received\",\"value\":\"from mail-io1-f52.google.com (mail-io1-f52.google.com [209.85.166.52]) by inbound-smtp.us-east-1.amazonaws.com with SMTP id a4ihukv3og9kbpb321fffe1kr0snb6q8m765so01 for [email protected]; Thu, 20 Feb 2020 05:36:27 +0000 (UTC)\"},{\"name\":\"X-SES-Spam-Verdict\",\"value\":\"PASS\"},{\"name\":\"X-SES-Virus-Verdict\",\"value\":\"PASS\"},{\"name\":\"Received-SPF\",\"value\":\"none (spfCheck: 209.85.166.52 is neither permitted nor denied by domain of icdesign.com.au) client-ip=209.85.166.52; [email protected]; helo=mail-io1-f52.google.com;\"},{\"name\":\"Authentication-Results\",\"value\":\"amazonses.com; spf=none (spfCheck: 209.85.166.52 is neither permitted nor denied by domain of icdesign.com.au) client-ip=209.85.166.52; [email protected]; helo=mail-io1-f52.google.com; dkim=pass [email protected]; dmarc=none header.from=icdesign.com.au;\"},{\"name\":\"X-SES-RECEIPT\",\"value\":\"AEFBQUFBQUFBQUFGeXE1bnBtYWdURERpWSs4NWd1NkdGNXZQMkthcVN0MHlRSElQakJDa3hURTJSaWhTZE1tTGVuTngzTFNQcjFnOHBOV0hmTTgyQmtDYnAzWjBRQ3F0b3poMXgrMWthOWtGaXU0YThTbjdQV1ozRHFQak9ndklRbThBTHRPZkI3N2w3cjE0SHEwTi8vLzRidWlYR0hMR2xoZ3pwaUovRnZZQ3pmcmpZTytWUUhvNXpIaVRlMms3UEtrK0J5SHhyYkQzelVoNU1nbzdrWTQ0K2ZFaEowbEtKSHN2VE16M3RGQ0M1Q1YwbkpiRVdRNHArZGcvNUx0NkRtcDZQTGlDNDhIajZ1Q3A3UDJWdVJ3dm9wb0d1TlhHazFOZTBGZ1RIdVMycXZ4WWpRNTVObkE9PQ==\"},{\"name\":\"X-SES-DKIM-SIGNATURE\",\"value\":\"a=rsa-sha256; q=dns/txt; b=HZ7v48TOjAatg1OXx3T3q2PEbAFhZDNzpqZcpjC6rNcuc4hewkcX8TRu/UXmw7buwtyL7WhAFY5O0TCidMAdgRpdqhk2HI3AVqYRhnUCcCrJplbzd2eXzSRUoOMCLbi/nb42UnYQ7bLsFRKfIdlNJAfJjQTtVWD1clbz8YLQeKQ=; c=relaxed/simple; s=6gbrjpgwjskckoa6a5zn6fwqkn67xbtw; d=amazonses.com; t=1582176987; v=1; bh=E9Ja8Uhnyy+9uwFbAikF555UU8SL3+Q7ZYz4q9ioAyM=; h=From:To:Cc:Bcc:Subject:Date:Message-ID:MIME-Version:Content-Type:X-SES-RECEIPT;\"},{\"name\":\"Received\",\"value\":\"by mail-io1-f52.google.com with SMTP id c16so3310276ioh.6 for <[email protected]>; Wed, 19 Feb 2020 21:36:27 -0800 (PST)\"},{\"name\":\"DKIM-Signature\",\"value\":\"v=1; a=rsa-sha256; c=relaxed/relaxed; d=icdesign-com-au.20150623.gappssmtp.com; s=20150623; h=mime-version:references:in-reply-to:from:date:message-id:subject:to; bh=IGwXLb069GUVEzjNT9VZNLusA/JJ+0oQCY2up9Ji1iE=; b=PLb5pJHBIrfxFqWLeIoPAN2iK6XsYzAVedHW37lkteKUjbOkKoUH416p5EnXG5HMvzlHmvFVr7IA0Ixfvvynr2d56kyaa3xxJ5ah/qpHiYTyl5iXZk8l5NJZC3VGVyYc+S8wvpgvx/CXfnu00+XieNlYSt3Lu8OdvNU02Xtca3heIPe80Qm4110Yz5KUSeyZn32qwRsch0Goe26uP/nJqpQiDFMVX3d0tQse8Esrtwz4YQxAg/TfpepdOtKofauCw81yS27ig7kb6D5mVSWlHv/1kBhe9HzGHIBL/J4q9K5vMRhVmNCc1a7sgvaQtJw7VFypWWHBK+VobD1fbNRrdw==\"},{\"name\":\"X-Google-DKIM-Signature\",\"value\":\"v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to; bh=IGwXLb069GUVEzjNT9VZNLusA/JJ+0oQCY2up9Ji1iE=; b=M1DiXv0+3JVifdbwNrKzyv8sheSGaYBbUBmdEwd5LYFuYUfUtV6wWXgf5DQ3rGKwyI GaH7cYE+H0tEP2ugrJoc7rWzcrsuNKX3OxZQ9BR4Ezkm2DCPBiAkrF5VS8ZiEXgxnuYx An6e1hbVqLNnZZJ4sNnaumtn/KxicacQXS3CKp0Xtv4UViQn28BoSE1mFeZypxDFmqti GRWaNPsk3Bx6Vebmi2tpBYLx2r3QPt2ef+vqZCSBZYh4Uh0ejpkPzAPn7pkklZ36NGsd 689pdCOA5bWS61tBr8EqPa1GJThx4qQAbGTFE/P7TfF9+4Wzuw9qwksuQuYtVGHBKqO7 Zrlw==\"},{\"name\":\"X-Gm-Message-State\",\"value\":\"APjAAAUjyNFViKnpA6PAWIzjq9HSOYmYHSGI3rQGrYLl3H27JYxz1byh R4Ey//04M7zM09fgSUPLcwXoSofULRMZ+inF9Bii51yVkQ==\"},{\"name\":\"X-Google-Smtp-Source\",\"value\":\"APXvYqyDhvRo4x6AcQ9hjhn7ii2AcucVb0s3Nkp40K9t0LepVmy1wZURPtPdx6PjWevWbrTv76mywwjczaTGaZTbdmg=\"},{\"name\":\"X-Received\",\"value\":\"by 2002:a05:6602:2113:: with SMTP id x19mr23776820iox.227.1582176985517; Wed, 19 Feb 2020 21:36:25 -0800 (PST)\"},{\"name\":\"MIME-Version\",\"value\":\"1.0\"},{\"name\":\"References\",\"value\":\"<CABBvxbFb2nQHDuL0YRixxa3ntoyOxQq_R-s9jJbaLPqAdEBFMw@mail.gmail.com>\"},{\"name\":\"In-Reply-To\",\"value\":\"<CABBvxbFb2nQHDuL0YRixxa3ntoyOxQq_R-s9jJbaLPqAdEBFMw@mail.gmail.com>\"},{\"name\":\"From\",\"value\":\"Thomas Sinclair <[email protected]>\"},{\"name\":\"Date\",\"value\":\"Thu, 20 Feb 2020 16:36:12 +1100\"},{\"name\":\"Message-ID\",\"value\":\"<CABBvxbEEu4v4w14su3tqWEw05NQG-31ceyyiPRWn96vkDZv3bQ@mail.gmail.com>\"},{\"name\":\"Subject\",\"value\":\"Fwd: Another test\"},{\"name\":\"To\",\"value\":\"[email protected]\"},{\"name\":\"Content-Type\",\"value\":\"multipart/mixed; boundary=\\\"000000000000321454059efb499f\\\"\"}],\"commonHeaders\":{\"returnPath\":\"[email protected]\",\"from\":[\"Thomas Sinclair <[email protected]>\"],\"date\":\"Thu, 20 Feb 2020 16:36:12 +1100\",\"to\":[\"[email protected]\"],\"messageId\":\"<CABBvxbEEu4v4w14su3tqWEw05NQG-31ceyyiPRWn96vkDZv3bQ@mail.gmail.com>\",\"subject\":\"Fwd: Another test\"}},\"receipt\":{\"timestamp\":\"2020-02-20T05:36:27.448Z\",\"processingTimeMillis\":611,\"recipients\":[\"[email protected]\"],\"spamVerdict\":{\"status\":\"PASS\"},\"virusVerdict\":{\"status\":\"PASS\"},\"spfVerdict\":{\"status\":\"GRAY\"},\"dkimVerdict\":{\"status\":\"GRAY\"},\"dmarcVerdict\":{\"status\":\"GRAY\"},\"action\":{\"type\":\"S3\",\"topicArn\":\"arn:aws:sns:us-east-1:104720634813:SESS3Upload\",\"bucketName\":\"thomas-marketboomer-test\",\"objectKeyPrefix\":\"\",\"objectKey\":\"a4ihukv3og9kbpb321fffe1kr0snb6q8m765so01\"}}}",
              "Timestamp": "2020-02-20T05:36:28.081Z",
              "SignatureVersion": "1",
              "Signature": "l4/eCmRAJyRu3oaOyywUeM/uqaU9cY5H2WJ+zDGXYMD0giOMv6e1HxH3c+oxWDDwN5F2e5dIonSnFMGLrY3sw++AFja9hWvqpvFTFSq0IGpHRImDB9iqdrJO7y8TgXHErGxYrT+WxobstHkHl5IgQiFDLGMt9WlHufp0CLdb1xOTv6cNutXeaN6MoN0lRKXWQozEIeUZfCD30xfhnUL5Sk28aBgp6sIXGcnB549dXvh/btz8HEdbGVEQKbkr82Sq1mizUAs9KrHVhNNFsweUYdglkSWe+p/Pyp/QggsPDBEBcjribvyUyYIhHQWIZxQ8UFVEBZCCWQRMVUDLLAmtHw==",
              "SigningCertUrl": "https://sns.us-east-1.amazonaws.com/SimpleNotificationService-a86cb10b4e1f29c941702d737128f7b6.pem",
              "UnsubscribeUrl": "https://sns.us-east-1.amazonaws.com/?Action=Unsubscribe&SubscriptionArn=arn:aws:sns:us-east-1:104720634813:SESS3Upload:aab9a0d2-79bc-4140-9bdb-c2029a22b0bb",
              "MessageAttributes": {}
          }
      }
  ]
}