IMAP Watcher

This application watches one or more IMAP accounts for incoming messages via IMAP IDLE. In case a new message is received, it triggers an external script, that might do further actions.

For example we are using this application, to send push notifications via ntfy in case of incoming messages. The example callback script callback/ntfy.sh illustrates, how to send those push notifications for incoming emails.

How to install

Make sure, you have Python 3 and virtualenv installed. Clone the repository, enter the repository root and run init.sh to download all dependencies.

git clone https://github.com/OpenIndex/IMAPWatcher.git
cd IMAPWatcher
./init.sh

How to configure

Take a look at config.example.ini. It describes all available configuration options. Just copy the example file to any location you like and make your changes.

You might setup as many IMAP accounts as you like within one configuration file.

How to setup the callback script

In your config.ini you should provide for each mail account a callback script, that is called for each newly received message - e.g. the example script

on_new_message = ./callback/printenv.sh

can be used to see all passed environment variables.

These environment variables with informations about the incoming message are passed to the callback script:

variable	example value	description
MESSAGE_ID	<[email protected]>	Message-Id header value
MESSAGE_REPLY_TO_ID	<[email protected]>	In-Reply-To header value
MESSAGE_DATE	2023-07-12 23:31:07	message date
MESSAGE_SENDER	John Doe <[email protected]>	complete Sender header value
MESSAGE_SENDER_NAME	John Doe	name part of Sender header value
MESSAGE_SENDER_MAIL	[email protected]	mail part of Sender header value
MESSAGE_FROM	John Doe <[email protected]>	complete From header value
MESSAGE_FROM_NAME	John Doe	name part of From header value
MESSAGE_FROM_MAIL	[email protected]	mail part of From header value
MESSAGE_AUTHOR	John Doe <[email protected]>	either MESSAGE_FROM or MESSAGE_SENDER
MESSAGE_AUTHOR_NAME	John Doe	either MESSAGE_FROM_NAME or MESSAGE_SENDER_NAME
MESSAGE_AUTHOR_MAIL	[email protected]	either MESSAGE_FROM_MAIL or MESSAGE_SENDER_MAIL
MESSAGE_TO	Frank Doe <[email protected]>	complete To header value
MESSAGE_TO_NAME	Frank Doe	name part of To header value
MESSAGE_TO_MAIL	[email protected]	mail part of To header value

The variables MESSAGE_AUTHOR, MESSAGE_AUTHOR_NAME and MESSAGE_AUTHOR_MAIL are some kind of special. By default they contain the From header value. But if the From header is not present, the Sender header value is used instead.

Also you might pass additional environment variables to the callback script - e.g. if the mail account in config.ini contains

env_additional_variable = test1
env_another_additional_variable = test2

also the following environment variables are passed:

ADDITIONAL_VARIABLE=test1
ANOTHER_ADDITIONAL_VARIABLE=test2

Take a look at callback/ntfy.sh as an example, how to send push notifications for incoming email messages (via ntfy) by using some of the provided environment variables.

How to run

Assuming your configuration file is called config.ini, you might test the settings first via:

./run-config-test.sh config.ini

If connection to all configured IMAP accounts was successful, you can run IMAP Watcher via:

./run.sh config.ini

For a first test of the callback mechanism you should run the application in foreground and send a test mail to your configured account.

If the callback mechanism works as expected, feel free to setup a cronjob or Systemd service.

FAQ

Does it work with gmail or other providers using OAuth?

OAuth is currently not supported as we don't need it for our daily work. Feel free to provide a pull request. We also take donations for improvements like that.