smtp_gateway is a library for receiving SMTP messages.
smtp_gateway::listen accepts any incoming TCP connection and
spawns a new task to handle it as an SMTP session.
When an SMTP session finishes with a received message,
it is passed to the consumer to handle.
smtp_gateway accepts messages but it cannot send or relay messages. An SMTP gateway receives messages in SMTP and transform them for retransmission. smtp_gateway exists to handle the first part of this goal, and it is up to the consumer to handle transformation and retransmission.
For a real example of what this looks like, see smtp_gateway_bot.
This is what smtp_gateway was developed for,
and can be found in ./smtp_gateway_bot.
smtp_gateway uses specific terminology (such as "client" and "server") as defined by RFC 5321 section 2.3. Pull requests and issues to fix discrepancies are welcome.
smtp_gateway is currently in development, code quality is not a high priority. Pull requests and issues are welcome, especially for pointing out or correcting issues regarding non-compliance with the SMTP specification.
Code is designed largely just to reach the next part of the specification to follow, not for flexibility. Once I have finished reading the specification and the first draft of the implementation, I will likely rewrite the library with an eye for quality and maintainability.
smtp_gateway is licensed under the GNU Affero General Public License version 3, or (at your option) any later version. You should have received a copy of the GNU Affero General Public License along with smtp_gateway, found in LICENSE. If not, see https://www.gnu.org/licenses/.