Running Horus#

Launching Horus#

For macOS and Ubuntu 22+#

To open Horus, simply click the Horus icon.

Command Line Options#

On both macOS and Linux, Horus supports advanced command line arguments. Use the --help command to view all the available options. Please replace Horus in the command with the actual path for your Horus installation. For linux, it should be in the PATH, but on macOS, the executable is found under the Horus.app.

# For macOS
/Applications/Horus.app/Contents/MacOS/Horus --help

# If you have the executable in the PATH or an alias
horus --help

By default, Horus uses a random port. If you want to fix the port to have the same URL always, use the -p and -h parameters.

Environment Variables#

In addition to command-line options, Horus allows configuration through the following environment variables:

  • HORUS_APP_SUPPORT_DIR: Specifies the directory path for the App Support folder, which holds user configurations, remotes, and installed plugins.

  • HORUS_DEFAULT_PLUGINS_DIR: Defines the path for default plugins that cannot be uninstalled. The default Horus plugin is located here. By default, this is set to app_support_dir/DefaultPlugins.

  • HORUS_PLUGINS_DIR: Indicates the directory for user-installed plugins. By default, this points to app_support_dir/Plugins.

  • HORUS_PUBLIC_FLOWS: Directory for public flows. Intended to be used in WebApp mode.

  • HORUS_ROOT: Root path where the server runs. Defaults to “/”.

  • HORUS_GUI: Sets the GUI backend to be used. Available options are QT and GTK (Linux only), or Cocoa (macOS).

  • HORUS_MODE: Specifies the application mode. Valid values are app, browser, server, or webapp.

  • HORUS_PORT: Defines the port for the Horus server.

  • HORUS_HOST: Specifies the host for the Horus server.

App Mode (Default Mode)#

This mode runs Horus standard in a windowed environment. Runs as a desktop application. It can also connect to a remote machine via SSH to send simulations.

Browser Mode#

In cases where you need all the capabilities of App Mode (such as file picker interactions with the OS), but the rest of the GUI (Mol*, the flow canvas, etc.) does not work well on the integrated GTK/Cocoa framework, you can use this mode. It opens a small window that redirects to your web browser at the specified Horus URL.

Server Mode#

This mode runs Horus entirely in server mode (no windowed app). You can connect using a browser to the application. This mode is intended for running Horus in a remote machine, where a URL will be provided to the user to connect using a web browser. Usually, port forwarding or a VPN will be required to access it from outside of your local network.

WebApp Mode#

This mode is intended for running Horus in a private/public environment with user capabilities, registration, etc. For more information, please refer to the WebApp mode section.

Security considerations#

Horus does not manage TLS or HTTPS directly. Instead, a reverse proxy (e.g., Nginx) should be used to enable encrypted communications and manage HTTPS certificates.

  • Use Server Mode only within a secured company network (via VPN).

  • Configure a reverse proxy for TLS/HTTPS encryption in WebApp mode.

  • Ensure access control for remote connections in App Mode (e.g., SSH keys).

  • Keep Horus and its dependencies updated to mitigate vulnerabilities.