Running The Lona Module


Added in 1.4.1

Lona can run from its command line tool lona or by using python -m lona. Both calls share the same command line arguments

lona run-server -s --port=8080
python -m lona run-server -s --port=8080

Lona Server Command Line Options


When using a GNU make based project like in the Getting Started you can use args="" to set command line options

make server args="--host= --port=80 --shell"

Option Description
-l / --log-level Set log level to [debug,info,warn,error,critical]
--loggers Enable or disable a given list of loggers
To include a logger use "+{LOGGER_NAME}", to exclude "_{LOGGER_NAME}"
--debug-mode Enable debug log for {messages,views,input-events,view-events}
--shell Embed a shell in the same process as the server
--shell-server Starts rlpython shell server containing a Lona shell
More Information: Lona Shell
-o Set setting to value before got loaded
example "-o MY_FEATURE=True"
-O Set setting to value after got loaded
example "-o MY_FEATURE=True"

Lona Client


Changed in in 1.10: settings.CLIENT_RECOMPILE was renamed to settings.CLIENT_DEBUG


By default the Lona client and all its discovered modules get compiled once at startup. To recompile on every request you can set settings.CLIENT_DEBUG to True or use -O CLIENT_DEBUG=True from the command line.

When settings.CLIENT_DEBUG is set, Lona does not merge the clients source files together, to make Chrome Inspector work as expected.


To test View Start Timeouts you can set settings.TEST_VIEW_START_TIMEOUT to True or use -O TEST_VIEW_START_TIMEOUT=True from the command line.

When this setting is set, Lona will introduce an arbitrary delay of settings.CLIENT_VIEW_START_TIMEOUT plus 1 Second before a view gets started.


To test View Input Event Timeouts you can set settings.TEST_INPUT_EVENT_TIMEOUT to True or use -O TEST_INPUT_EVENT_TIMEOUT=True from the command line.

When this setting is set, Lona will introduce an arbitrary delay of settings.CLIENT_INPUT_EVENT_TIMEOUT plus 1 Second before an input event gets handled.

Lona Shell


LonaView.embed_shell and server.embed_shell were removed in 1.8.

The Lona shell is based on rlpython and can be started directly from the server process using --shell, when using script using and a shell server and can be embedded using server.embed_shell() or LonaView.embed_shell().

The shell is a full python REPL and contains some use full commands prefixed with %lona_.

Command Description
%threads [THREAD_ID] Prints all threads or all information on given thread
%lona_info Prints basic information about the running Lona server
and its configuration
%lona_settings [SETTINGS_NAME] Prints one or all settings
%lona_routes [-r URL] Prints all or the matching routes when URL is provided
%lona_connections Prints all current server connections
%lona_server_state Prints server.state
%lona_views [RUNTIME_ID] [--memory] Prints all running views or all information on given
view. When "--memory" is set, all current variables
of the view get printed
%lona_static_files [-l] [-r NAME] [static-dir] Prints all loaded static files or static file directories
%lona_templates [-l] [-r NAME] [template-dir] Prints all loaded templates or template directories
%lona_middlewares Prints all loaded middleware hooks

Using Lona Shell Server

Lona supports rlpython's remote shell feature. With --shell-server set Lona server binds to a port or a unix domain socket.

$ lona run-server --shell-server=file://socket
$ lona run-server --shell-server=localhost:8080

To attach run

$ rlpython file://socket
$ rlpython localhost:8080

or if you use the project template from Getting Started you can run

$ make server-shell