emailer

README

Emailer

Purpose

Packaging SMTP(send only) APIs to a choosable option is the goal here, then to have a tiny server that picks 1 provider and serves as HTTP endpoint so the other microservices that belong to you can make email requests.

Supported providers

• Brevo (highly recommended)
• Resend
• Postmark
• Mailchimp
• Mailtrap
• Mailjet
• Mailgun
• Sendgrid (avoid them if you can)

Note: Anything that only uses oauth2 like zoho does will not be implemented here for foreseeable future

Getting Started

  export API_KEY=<SECRET_API_KEY>
  export PROVIDER=brevo
  go run ./cmd/emailer/main.go -debug

Kick the server by after having PROVIDER and API_KEY env variables then run go run ./cmd/emailer/main.go

Send Emails

This endpoint allows you to send an email by providing the necessary email details in the request body as JSON.

• Method: POST
• URL: /email
• Request:

  • {
      "from": "sender@example.com",
      "to": ["recipient1@example.com", "recipient2@example.com"],
      "bcc": ["bcc1@example.com", "bcc2@example.com"],
      "cc": ["cc1@example.com", "cc2@example.com"],
      "subject": "Test Email",
      "htmlContent": "<p>This is a test email in HTML format.</p>",
      "textContent": "This is a test email in plain text format."
    }
    

• Response:
  • 200 Email successfully sent
  • 400 Encoding error or Failed to validate
  • 500 Failed to send email (check logs something went wrong with the provider)

  curl -X POST http://localhost:5555/email \
  -H "Content-Type: application/json" \
  -d '{
    "from": "sender@example.com",
    "to": ["recipient@example.com"],
    "subject": "Test Email",
    "htmlContent": "<p>This is a test email in HTML format.</p>",
    "textContent": "This is a test email in plain text format."
  }'

Documentation

Overview

Package emailer provides shared foundation stones for email providers

Index

• func HandlerFunc(sender Sender) http.HandlerFunc
• type Config
• type Email
  • func (e Email) ValidationMsg() string
• type Sender

Functions

func HandlerFunc

func HandlerFunc(sender Sender) http.HandlerFunc

HandlerFunc is opinionated/reusable HTTP handler for brevo provider

Types

type Config

type Config struct {
	Key string
	http.Client
}

Config configures the email clients

type Email

type Email struct {
	From        string   `json:"from"`
	To          []string `json:"to"`
	BCC         []string `json:"bcc"`
	CC          []string `json:"cc"`
	Subject     string   `json:"subject"`
	HTMLContent string   `json:"htmlContent"`
	TextContent string   `json:"textContent"`
}

Email is generic email structure for all providers

func (Email) ValidationMsg

func (e Email) ValidationMsg() string

ValidationMsg returns empty if all validations passed, else it will return failed validation message

type Sender

type Sender interface {
	Send(ctx context.Context, e Email) error
}

Sender is a behaviour for email senders