How to create a fake mail server on localhost

Creating a fake mail server on localhost can be useful for testing email-related functionality, such as sending and receiving emails, without actually sending emails to real mail servers. Here are a few ways to create a fake mail server on localhost:

Method 1: Using Mailhog

Mailhog is a popular, open-source tool that allows you to capture and inspect emails sent to your application. It's easy to set up and use.

  1. Install Mailhog using npm or yarn: npm install -g mailhog or yarn global add mailhog
  2. Start Mailhog: mailhog
  3. Mailhog will start a fake mail server on localhost:1025 and a web interface on http://localhost:8025
  4. Configure your application to send emails to localhost:1025 instead of a real mail server
  5. Inspect emails in the Mailhog web interface or using the mailhog command-line tool

Method 2: Using a Python script

You can create a simple Python script to act as a fake mail server using the smtpd module.

  1. Create a new Python file (e.g., fake_smtp.py)
  2. Add the following code:
    
import smtpd
import asyncore

class FakeSMTPServer(smtpd.SMTPServer): def process_message(self, peer, mailfrom, rcpttos, data): print(f"Received email from {mailfrom} to {rcpttos}")

You can also store the email in a file or database here

if name == "main": server = FakeSMTPServer(("localhost", 2525), None) asyncore.loop()


3. Run the script: `python fake_smtp.py`
4. Configure your application to send emails to `localhost:2525` instead of a real mail server
5. The script will print the received email to the console

**Method 3: Using a Docker container**

You can use a Docker container to run a fake mail server. One popular option is `mailserver`:

1. Install Docker: `docker run -d --name mailserver mailserver/mailserver`
2. Configure your application to send emails to `localhost:25` instead of a real mail server
3. The `mailserver` container will capture and store the emails in a database

These are just a few examples of how you can create a fake mail server on localhost. You can choose the method that best fits your needs.