email-gateway

Email Gateway

• Email Gateway
  • API Specification
  • Getting Started
    • Prerequisites
    • Configuration
    • Installing & Running Locally
  • Running the tests
  • Deployment
  • Built With

• This is example gateway built with Spring Boot and the gateway library to send email messages to customers.
• Use this project as a reference guide to integrate the gateway library into your own project.
• The gateway receives a user ID and generates a report containing antivirus and anti-malware statistics for the month and sends it to the user's email address.
• For simplicity, this gateway uses an in-memory database and the statistics are randomly generated when the gateway starts up. The email address for each user is passed in as an environment variable. See configuration section for more details.
  • User 1:
    • ID: 62f8a8e1-f55a-4d9a-ab15-852168a321a4
    • First Name: Cameron
  • User 2:
    • ID: f882fa87-c249-4c14-bb61-78542217f79d
    • First Name: Cameron
• Check SPAM folders if the email is not received in the inbox.

API Specification

See swagger specification for gateways for request body and header requirements. This gateway exposes the endpoint POST /email/monthly-report to generate a monthly report and send it to a customer.

Getting Started

Follow these instructions to run the project locally and configure for kubernetes deployment

Prerequisites

Ensure you have the following installed or configured:

• Java 21
• Maven 3.8.7 or newer
• History database (AWS DynamoDB) with the schema defined here
  • Deploy one using the Terragrunt library
• Sendgrid account to send emails
  • Follow the documentation to create an API key.
  • Create a dynamic template. Optionally add the following fields in the template to use the data generated by the gateway in the email
    • name
    • subject
    • malware
    • adverts
    • sites
    • The template should look like this when completed:
    • 

Configuration

This section describes the configuration options available for the gateway via environment variables and spring profiles

• Run the project with the ssl profile to enable SSL
• To generate a self-signed keystore file for development purposes, run the following command in the project directory:
  • keytool -genkeypair -alias email-gateway -keyalg RSA -keysize 2048 -storetype PKCS12 -keystore email-gateway.p12 -validity 3650
    • Follow prompts to set the keystore password.
    • Place the generated file in src/main/resources/keystore
  • If you don't want to place the file in the resources folder:
    • Run base64 -e -i .\email-gateway.p12 -o email-gateway-base64.txt to encode the keystore file for use in kubernetes secrets that will set the GATEWAY_API_SSL_KEY_STORE to be the data in the text file you've just generated.

Caution

Setting CORS_ENABLED or CSRF_ENABLED to false should NOT be used in a live production environment, it should only be used when testing with self-signed SSL certificates.

Environment Variable	Description	Default Value	Required
EMAIL_NEWSLETTER_API	Your Sendgrid API key. It should start with "SG."		Y
FROM_EMAIL	The email address that the will be used to send the message		Y
FROM_NAME	The name of the sender		Y
MONTHLY_NEWSLETTER_TEMPLATE_ID	The dynamic template ID created in Sendgrid		Y
USER1_EMAIL	The email address belonging to User 1 (ID: 62f8a8e1-f55a-4d9a-ab15-852168a321a4), this is the recipient address if a request is made using this ID		Y
USER2_EMAIL	The email address belonging to User 2 (ID: f882fa87-c249-4c14-bb61-78542217f79d), this is the recipient address if a request is made using this ID		Y
WORKER_API_KEY	A secret key to authenticate requests. Requests must include this key as a header labelled x-worker-api-key. This should be set to the value that the worker will send in the request header.		Y
REGION	The region of the DynamoDB table. E.g. "eu-west-1"	eu-west-1	Y
COMMUNICATION_HISTORY_TABLE_NAME	The name of the DynamoDB table	communication-history	Y
EMAIL_GATEWAY_SSL_KEY_STORE_PASSWORD	The keystore password to access the keystore		Y if using SSL profile
EMAIL_GATEWAY_SSL_KEY_STORE	The file path or file containing the public and private keys in PKCS12 format	classpath:keystore/email-gateway.p12	N
ROOT_LOGGING	The root logging level for the project	info	N
GATEWAY_LOGGING	The logging level for the gateway library	info	N
CORS_ENABLED	Sets the CORS check when processing a request. Set to false for testing purposes to disable	true	N
CSRF_ENABLED	Sets the CSRF check when processing a request. Set to false for testing purposes to disable	true	N

Installing & Running Locally

Follow the instructions below to get a development environment running:

1. Clone the repository
2. Navigate to the project directory
3. Run mvn clean install to build and test the project
4. Run mvn spring-boot:run to start the server
   • Run mvn spring-boot:run -Dspring-boot.run.profiles=ssl to start the server with SSL enabled (requires extra configuration)

Running the tests

• To run the unit tests, run mvn test in the project directory
• To run the integration tests see the Integration Tests Project and make sure that the @EmailGateway is added to the filter expression.

Deployment

• Run the command from the project root to build and push a new image for both arm and amd platforms.
  • docker buildx build --platform linux/amd64,linux/arm64 -t <account name>/<image-name>:<image-tag> --push .
• See helm deployment to deploy the Email Gateway to a kubernetes cluster.

Built With

• Spring Boot
• Maven
• Gateway Library
• Sendgrid