MantisBTMailTask

A cross-platform background service (Windows Service / systemd daemon) that processes the outgoing mail queue for MantisBT.

Background

MantisBT's PHP-based mail subsystem can be difficult to configure correctly in some environments. This project replaces it with a standalone .NET hosted service that reads pending notifications directly from the MantisBT database and sends them via email, making the process easier to configure, run, and debug.

The original implementation sent mail over SMTP; that version is preserved on the SMTP_Client branch. The current version uses Microsoft.Graph to send mail through Exchange Online.

Prerequisites

• Access to the MantisBT database
• An Azure AD app registration with permissions to send mail via Microsoft Graph (Mail.Send), used to obtain the TenantId, ClientId, and ClientSecret below

Installation

1. Disable mail delivery from the MantisBT web application by adding the following line to your config_inc.php, which defers mail sending to this service instead:

   $g_email_send_using_cronjob = ON;

2. Download the latest release artifact from the Releases page:

   • MantisBTMailTask-<version>-win-x64.zip for Windows — a win-x64 build that includes MantisBTMailTask.exe
   • MantisBTMailTask-<version>.zip / MantisBTMailTask-<version>.tgz for Linux — a framework-dependent build (requires the matching .NET runtime to be installed) that also includes the sample systemd unit file

   These are built and published automatically by the project's GitHub Actions release workflow.

3. Extract the archive contents to the location you want to run the service from. The archive includes appsettings.json and, for Linux, the sample mantisbtmailtask.service unit file.

4. Update appsettings.json with your environment's configuration (see Configuration below). Only the minimum required settings are included in the default file.

5. Install the service for your operating system:

   Windows

   sc create MantisBTMailTask BinPath=<INSTALL FOLDER>\MantisBTMailTask.exe
   sc start MantisBTMailTask

   Linux

   A sample unit file is provided at mantisbtmailtask.service. Copy the published files to /opt/mantisbtmailtask (or update the paths in the unit file to match your install folder), then run:

   sudo useradd --system --no-create-home --shell /usr/sbin/nologin mantisbtmailtask
   sudo cp mantisbtmailtask.service /etc/systemd/system/
   sudo systemctl daemon-reload
   sudo systemctl enable --now mantisbtmailtask
   sudo systemctl status mantisbtmailtask

Configuration

Settings are read from appsettings.json.

Section	Key	Description	Default
MantisDB	Host	MantisBT database hostname	localhost
MantisDB	Port	MantisBT database port	3306
MantisDB	Database	MantisBT database name	(required)
MantisDB	Username	MantisBT database username	(required)
MantisDB	Password	MantisBT database password	(required)
MailServer	TenantId	Azure AD tenant ID	(required)
MailServer	ClientId	Azure AD app registration client ID	(required)
MailServer	ClientSecret	Azure AD app registration client secret	(required)
MailServer	From	Mailbox address mail is sent from	(required)
MailServer	ForceRemoveOnFailure	Remove emails from the queue even if they fail to send	false

Building

If you want to build from source instead of using a released artifact:

1. Install the .NET SDK version matching the one used by the release workflow (currently 10.0.x).
2. Restore and build the solution:

   dotnet restore
   dotnet build --configuration Release

3. Publish the service. On Windows this produces a Windows Service host; on Linux it produces a systemd-compatible daemon:

   dotnet publish MantisBTMailTask/MantisBTMailTask.csproj --configuration Release --output publish

4. Copy the contents of the publish folder, along with mantisbtmailtask.service on Linux, to the location you want to run the service from, then continue from step 4 of Installation.

License

This project is licensed under the MIT License.