# Developer Plugin Documentation Plugins allow you to customise and extend the behavior of EDMC. ## Installing a Plugin See [Plugins](https://github.com/EDCD/EDMarketConnector/wiki/Plugins) on the wiki. ## Writing a Plugin Plugins are loaded when EDMC starts up. Each plugin has it's own folder in the `plugins` directory: - Windows: `%LOCALAPPDATA%\EDMarketConnector\plugins` - Mac: `~/Library/Application Support/EDMarketConnector/plugins` - Linux: `$XDG_DATA_HOME/EDMarketConnector/plugins`, or `~/.local/share/EDMarketConnector/plugins` if `$XDG_DATA_HOME` is unset. Plugins are python files. The plugin folder must have a file named `load.py` that must provide one module level function and optionally provide a few others. --- ### Examples We have some example plugins available in the docs/examples directory. See the readme in each folder for more info. --- ### Available imports **`import`ing anything from the core EDMarketConnector code that is not explicitly mentioned here is unsupported and may lead to your plugin breaking with future code changes.** `import L10n` - for plugin localisation support. `from theme import theme` - So plugins can theme their own UI elements to match the main UI. `from config import appname, applongname, appcmdname, appversion , copyright, config` - to access config. `from prefs import prefsVersion` - to allow for versioned preferences. `from companion import category_map` - Or any of the other static date contained therein. NB: There's a plan to move such to a `data` module. `import plug` - Mostly for using `plug.show_error()`. Also the flags for `dashboard_entry()` to be useful (see example below). Relying on anything else isn't supported. `from monitor import gamerunning` - in case a plugin needs to know if we think the game is running. `import timeout_session` - provides a method called `new_session` that creates a requests.session with a default timeout on all requests. Recommended to reduce noise in HTTP requests ```python from ttkHyperlinkLabel import HyperlinkLabel import myNotebook as nb ``` For creating UI elements. --- ### Logging In the past the only way to provide any logged output from a plugin was to use `print(...)` statements. When running the application from the packaged executeable all output is redirected to a log file. See [Reporting a problem](https://github.com/EDCD/EDMarketConnector/wiki/Troubleshooting#reporting-a-problem) for the location of this log file. EDMC now implements proper logging using the Python `logging` module. Plugin developers should now use the following code instead of simple `print(...)` statements. Insert this at the top-level of your load.py file (so not inside `plugin_start3()` ): ```python import logging from config import appname # This could also be returned from plugin_start3() plugin_name = os.path.basename(os.path.dirname(__file__)) # A Logger is used per 'found' plugin to make it easy to include the plugin's # folder name in the logging output format. # NB: plugin_name here *must* be the plugin's folder name as per the preceding # code, else the logger won't be properly set up. logger = logging.getLogger(f'{appname}.{plugin_name}') # If the Logger has handlers then it was already set up by the core code, else # it needs setting up here. if not logger.hasHandlers(): level = logging.INFO # So logger.info(...) is equivalent to print() logger.setLevel(level) logger_channel = logging.StreamHandler() logger_formatter = logging.Formatter(f'%(asctime)s - %(name)s - %(levelname)s - %(module)s:%(lineno)d:%(funcName)s: %(message)s') logger_formatter.default_time_format = '%Y-%m-%d %H:%M:%S' logger_formatter.default_msec_format = '%s.%03d' logger_channel.setFormatter(logger_formatter) logger.addHandler(logger_channel) ``` Note the admonishment about `plugin_name` being the folder name of your plugin. It can't be anything else (such as a different string returned from `plugin_start3()`) because the code in plug.py that sets up the logger uses exactly the folder name. Our custom `qualname` and `class` formatters won't work with a 'bare' logger, and will cause your code to throw exceptions if you're not using our supplied logger. If running with 4.1.0-beta1 or later of EDMC the logging setup happens in the core code and will include the extra logfile destinations. If your plugin is run under a pre-4.1.0 version of EDMC then the above will set up basic logging only to the console (and thus redirected to the log file). If you're certain your plugin will only be run under EDMC 4.1.0 or newer then you can remove the `if` clause. Replace all `print(...)` statements with one of the following: ```python logger.info('some info message') # instead of print(...) logger.debug('something only for debug') logger.warning('Something needs warning about') logger.error('Some error happened') logger.critical('Something went wrong in a critical manner') try: ... except Exception: # This logs at 'ERROR' level. # Also automatically includes exception information. logger.exception('An exception occurred') try: ... except Exception as e: logger.debug('Exception we only note in debug output', exc_info=e) ``` Remember you can use [fstrings](https://www.python.org/dev/peps/pep-0498/) to include variables, and even the returns of functions, in the output. ```python logger.debug(f"Couldn't frob the {thing} with the {wotsit()}") ``` --- ### Startup EDMC will import the `load.py` file as a module and then call the `plugin_start3()` function. ```python def plugin_start3(plugin_dir: str) -> str: """ Load this plugin into EDMC """ print(f"I am loaded! My plugin folder is {plugin_dir}") return "Test" ``` The string you return is used as the internal name of the plugin. Any errors or print statements from your plugin will appear in `%TMP%\EDMarketConnector.log` on Windows, `$TMPDIR/EDMarketConnector.log` on Mac, and `$TMP/EDMarketConnector.log` on Linux. | Parameter | Type | Description | | :----------- | :---: | :------------------------------------------------------ | | `plugin_dir` | `str` | The directory that your plugin is located in. | | `RETURN` | `str` | The name you want to be used for your plugin internally | ### Shutdown This gets called when the user closes the program: ```python def plugin_stop() -> None: """ EDMC is closing """ print("Farewell cruel world!") ``` If your plugin uses one or more threads to handle Events then `stop()` and `join()` (to wait for their exit -- Recommended, not required) the threads before returning from this function. ## Plugin Hooks ### Configuration If you want your plugin to be configurable via the GUI you can define a frame (panel) to be displayed on its own tab in EDMC's settings dialog. The tab title will be the value that you returned from `plugin_start3`. Use widgets from EDMC's myNotebook.py for the correct look-and-feel. You can be notified when the settings dialog is closed so you can save your settings. You can use `set()`, `get()` and `getint()` from EDMC's `config.config` object to retrieve your plugin's settings in a platform-independent way. **Be sure to use a unique prefix for any settings you save so as not to clash with core EDMC or other plugins.** Use `numberFromString()` from EDMC's `l10n.Locale` object to parse input numbers in a locale-independent way. ```python import tkinter as tk from tkinter import ttk import myNotebook as nb from config import config from typing import Optional my_setting: Optional[tk.IntVar] = None def plugin_prefs(parent: nb.Notebook, cmdr: str, is_beta: bool) -> Optional[tk.Frame]: """ Return a TK Frame for adding to the EDMC settings dialog. """ global my_setting my_setting = tk.IntVar(value=config.getint("MyPluginSetting")) # Retrieve saved value from config frame = nb.Frame(parent) nb.Label(frame, text="Hello").grid() nb.Label(frame, text="Commander").grid() nb.Checkbutton(frame, text="My Setting", variable=my_setting).grid() return frame ``` | Parameter | Type | Description | | :-------- | :-----------: | :----------------------------------------------- | | `parent` | `nb.Notebook` | Root Notebook object the preferences window uses | | `cmdr` | `str` | The current commander | | `is_beta` | `bool` | If the game is currently a beta version | This gets called when the user dismisses the settings dialog: ```python def prefs_changed(cmdr: str, is_beta: bool) -> None: """ Save settings. """ config.set('MyPluginSetting', my_setting.get()) # Store new value in config ``` | Parameter | Type | Description | | :-------- | :----: | :-------------------------------------- | | `cmdr` | `str` | The current commander | | `is_beta` | `bool` | If the game is currently a beta version | ### Display You can also have your plugin add an item to the EDMC main window and update from your event hooks. This works in the same way as `plugin_prefs()`. For a simple one-line item return a `tk.Label` widget or a 2 tuple of widgets. For a more complicated item create a tk.Frame widget and populate it with other ttk widgets. Return `None` if you just want to use this as a callback after the main window and all other plugins are initialised. You can use `stringFromNumber()` from EDMC's `l10n.Locale` object to format numbers in your widgets in a locale-independent way. ```python from typing import Optional, Tuple import tkinter as tk status: Optional[tk.Label] def plugin_app(parent: tk.Frame) -> Tuple[tk.Label, tk.Label]: """ Create a pair of TK widgets for the EDMC main window """ global status label = tk.Label(parent, text="Status:") # By default widgets inherit the current theme's colors status = tk.Label(parent, text="", foreground="yellow") # Override theme's foreground color return (label, status) # later on your event functions can update the contents of these widgets def some_other_function() -> None: global status status["text"] = "Happy!" status["foreground"] = "green" ``` | Parameter | Type | Description | | :-------- | :---------------------------------------------: | :---------------------------------------------------------- | | `parent` | `tk.Frame` | The root EDMC window | | `RETURN` | `Union[tk.Widget, Tuple[tk.Widget, tk.Widget]]` | A widget to add to the main window. See below for more info | The return from plugin_app can either be any widget (Frame, Label, Notebook, etc.), or a 2 tuple of widgets. In the case of a 2 tuple, indices 0 and 1 are placed automatically in the outer grid on column indices 0 and 1. Otherwise, the only thing done to your return widget is it is set to use a columnspan of 2, and placed on the grid. You can dynamically add and remove widgets on the main window by returning a tk.Frame from `plugin_app()` and later creating and destroying child widgets of that frame. ```python from typing import Option import tkinter as tk from theme import theme frame: Optional[tk.Frame] = None def plugin_app(parent: tk.Frame) -> tk.Frame: """ Create a frame for the EDMC main window """ global frame frame = tk.Frame(parent) return frame def some_other_function_called_later() -> None: # later on your event functions can add or remove widgets row = frame.grid_size()[1] new_widget_1 = tk.Label(frame, text="Status:") new_widget_1.grid(row=row, column=0, sticky=tk.W) new_widget_2 = tk.Label(frame, text="Unhappy!", foreground="red") # Override theme's foreground color new_widget_2.grid(row=row, column=1, sticky=tk.W) theme.update(this.frame) # Apply theme colours to the frame and its children, including the new widgets ``` ### Events Once you have created your plugin and EDMC has loaded it there are three other functions you can define to be notified by EDMC when something happens: `journal_entry()`, `dashboard_entry()` and `cmdr_data()`. Your events all get called on the main Tkinter loop so be sure not to block for very long or the app will appear to freeze. If you have a long running operation such as sending or receiving data from an external server then you should do this in a separate worker Thread. You can send work items to the worker thread over a Queue. Tkinter is not thread-safe so you should not access any Tkinter resources (including widgets and variables) from worker threads - doing so may cause the app to crash intermittently. You can signal back to the main thread using Tkinter's `event_generate()` widget method, generating a user-defined event that you have previously registered with the [`bind_all()`](http://effbot.org/tkinterbook/tkinter-events-and-bindings.htm) widget method. See the [EDSM plugin](https://github.com/Marginal/EDMarketConnector/blob/master/plugins/edsm.py) for an example of these techniques. #### Journal Entry ```python def journal_entry( cmdr: str, is_beta: bool, system: str, station: str, entry: Dict[str, Any], state: Dict[str, Any] ) -> None: if entry['event'] == 'FSDJump': # We arrived at a new system! if 'StarPos' in entry: logger.info(f'Arrived at {entry["StarSystem"]} {entry["StarPos"') else: logger.info(f'Arrived at {entry["StarSystem"]}') ``` This gets called when EDMC sees a new entry in the game's journal. | Parameter | Type | Description | | :-------- | :--------------: | :--------------------------------------------------------------------- | | `cmdr` | `str` | Current commander name | | `is_beta` | `bool` | Is the game currently in beta | | `system` | `Optional[str]` | Current system, if known | | `station` | `Optional[str]` | Current station, if any | | `entry` | `Dict[str, Any]` | The journal event | | `state` | `Dict[str, Any]` | More info about the commander, their ship, and their cargo (see below) | Content of `state` (updated to the current journal entry): | Field | Type | Description | | :------------- | :-------------------------: | :-------------------------------------------------------------------------------------------------------------- | | `Captian` | `Optional[str]` | Name of the commander who's crew you're on, if any | | `Cargo` | `dict` | Current cargo | | `Credits` | `int` | Current credits balance | | `FID` | `str` | Frontier commander ID | | `Loan` | `Optional[int]` | Current loan amount, if any | | `Raw` | `dict` | Current raw engineering materials | | `Manufactured` | `dict` | Current manufactured engineering materials | | `Encoded` | `dict` | Current encoded engineering materials | | `Engineers` | `dict` | Current Raw engineering materials | | `Rank` | `Dict[str, Tuple[int, int]` | Current ranks, each entry is a tuple of the current rank, and age | | `Statistics` | `dict` | Contents of a Journal Statistics event, ie, data shown in the stats panel. See the Journal manual for more info | | `Role` | `Optional[str]` | Current role if in multi-crew, one of `Idle`, `FireCon`, `FighterCon` | | `Friends` | `set` | Currently online friend | | `ShipID` | `int` | Frontier ID of current ship | | `ShipIdent` | `str` | Current user-set ship ID | | `ShipName` | `str` | Current user-set ship name | | `ShipType` | `str` | Internal name for the current ship type | | `HullValue` | `int` | Current ship value, excluding modules | | `ModulesValue` | `int` | Value of the current ship's modules | | `Rebuy` | `int` | Current ship's rebuy cost | | `Modules` | `dict` | Currently fitted modules | A special "StartUp" entry is sent if EDMC is started while the game is already running. In this case you won't receive initial events such as "LoadGame", "Rank", "Location", etc. However the `state` dictionary will reflect the cumulative effect of these missed events. Similarly, a special "ShutDown" entry is sent when the game is quitted while EDMC is running. This event is not sent when EDMC is running on a different machine so you should not *rely* on receiving this event. #### Player Dashboard ```python import plug def dashboard_entry(cmdr: str, is_beta: bool, entry: Dict[str, Any]): is_deployed = entry['Flags'] & plug.FlagsHardpointsDeployed sys.stderr.write("Hardpoints {}\n".format(is_deployed and "deployed" or "stowed")) ``` This gets called when something on the player's cockpit display changes - typically about once a second when in orbital flight. | Parameter | Type | Description | | :-------- | :----: | :-------------------------------- | | `cmdr` | `str` | Current command name | | `is_beta` | `bool` | if the game is currently in beta | | `entry` | `dict` | Data from status.json (see below) | For more info on `status.json`, See the "Status File" section in the Frontier [Journal documentation](https://forums.frontier.co.uk/showthread.php/401661) for the available `entry` properties and for the list of available `"Flags"`. Refer to the source code of [plug.py](./plug.py) for the list of available constants. #### Getting Commander Data ```python def cmdr_data(data, is_beta): """ We have new data on our commander """ if data.get('commander') is None or data['commander'].get('name') is None: raise ValueError("this isn't possible") logger.info(data['commander']['name']) ``` This gets called when EDMC has just fetched fresh Cmdr and station data from Frontier's servers. | Parameter | Type | Description | | :-------- | :--------------: | :------------------------------------------------------------------------------------------------------- | | `data` | `Dict[str, Any]` | `/profile` API response, with `/market` and `/shipyard` added under the keys `marketdata` and `shipdata` | | `is_beta` | `bool` | If the game is currently in beta | #### Plugin-specific events ```python def edsm_notify_system(reply): """ `reply` holds the response from a call to https://www.edsm.net/en/api-journal-v1 """ if not reply: logger.info("Error: Can't connect to EDSM") elif reply['msgnum'] // 100 not in (1,4): logger.info(f'Error: EDSM {reply["msg"]}') elif reply.get('systemCreated'): logger.info('New EDSM system!') else: logger.info('Known EDSM system') ``` If the player has chosen to "Send flight log and Cmdr status to EDSM" this gets called when the player starts the game or enters a new system. It is called some time after the corresponding `journal_entry()` event. | Parameter | Type | Description | | :-------- | :--------------: | :--------------------------------------------------------------------------------------------- | | `reply` | `Dict[str, Any]` | Response to an API call to [EDSM's journal API target](https://www.edsm.net/en/api-journal-v1) | ```python def inara_notify_location(event_data): """ `event_data` holds the response to one of the "Commander's Flight Log" events https://inara.cz/inara-api-docs/#event-29 """ if event_data.get('starsystemInaraID'): logging.info(f'Now in Inara system {event_data["starsystemInaraID"]} at {event_data["starsystemInaraURL"]}') else: logger.info('System not known to Inara') if event_data.get('stationInaraID'): logger.info(f'Docked at Inara station {event_data["stationInaraID"]} at {event_data["stationInaraURL"]}') else: logger.info('Undocked or station unknown to Inara') ``` If the player has chosen to "Send flight log and Cmdr status to Inara" this gets called when the player starts the game, enters a new system, docks or undocks. It is called some time after the corresponding `journal_entry()` event. | Parameter | Type | Description | | :----------- | :--------------: | :----------------------------------------------------------------------------------------------------------- | | `event_data` | `Dict[str, Any]` | Response to an API call to [INARA's `Commander Flight Log` event](https://inara.cz/inara-api-docs/#event-29) | --- ```python def inara_notify_ship(event_data): """ `event_data` holds the response to an addCommanderShip or setCommanderShip event https://inara.cz/inara-api-docs/#event-11 """ if event_data.get('shipInaraID'): logger.info( f'Now in Inara ship {event_data['shipInaraID'],} at {event_data['shipInaraURL']} ) ``` If the player has chosen to "Send flight log and Cmdr status to Inara" this gets called when the player starts the game or switches ship. It is called some time after the corresponding `journal_entry()` event. | Parameter | Type | Description | | :----------- | :--------------: | :----------------------------------------------------------------------------------------------------------------------------- | | `event_data` | `Dict[str, Any]` | Response to an API call to [INARA's `addCommanderShip` or `setCommanderShip` event](https://inara.cz/inara-api-docs/#event-11) | ## Error messages You can display an error in EDMC's status area by returning a string from your `journal_entry()`, `dashboard_entry()` or `cmdr_data()` function, or asynchronously (e.g. from a "worker" thread that is performing a long running operation) by calling `plug.show_error()`. Either method will cause the "bad" sound to be played (unless the user has muted sound). The status area is shared between EDMC itself and all other plugins, so your message won't be displayed for very long. Create a dedicated widget if you need to display routine status information. ## Localisation You can localise your plugin to one of the languages that EDMC itself supports. Add the following boilerplate near the top of each source file that contains strings that needs translating: ```python import l10n import functools _ = functools.partial(l10n.Translations.translate, context=__file__) ``` Wrap each string that needs translating with the `_()` function, e.g.: ```python status["text"] = _('Happy!') # Main window status ``` If you display localized strings in EDMC's main window you should refresh them in your `prefs_changed` function in case the user has changed their preferred language. Translation files should reside in folder named `L10n` inside your plugin's folder. Files must be in macOS/iOS ".strings" format, encoded as UTF-8. You can generate a starting template file for your translations by invoking `l10n.py` in your plugin's folder. This extracts all the translatable strings from Python files in your plugin's folder and places them in a file named `en.template` in the `L10n` folder. Rename this file as `.strings` and edit it. See EDMC's own [`L10n`](https://github.com/EDCD/EDMarketConnector/tree/master/L10n) folder for the list of supported language codes and for example translation files. ## Python Package Plugins A _Package Plugin_ is both a standard Python package (i.e. contains an `__init__.py` file) and an EDMC plugin (i.e. contains a `load.py` file providing at minimum a `plugin_start3()` function). These plugins are loaded before any non-Package plugins. Other plugins can access features in a Package Plugin by `import`ing the package by name in the usual way. ## Distributing a Plugin To package your plugin for distribution simply create a `.zip` archive of your plugin's folder: - Windows: In Explorer right click on your plugin's folder and choose Send to → Compressed (zipped) folder. - Mac: In Finder right click on your plugin's folder and choose Compress. If there are any external dependencies then include them in the plugin's folder. Optionally, for tidiness delete any `.pyc` and `.pyo` files in the archive, as well as the `__pycache__` directory. ## Disable a plugin EDMC now lets you disable a plugin without deleting it, simply rename the plugin folder to append ".disabled". Eg, "SuperSpaceHelper" -> "SuperSpaceHelper.disabled" Disabled and enabled plugins are listed on the "Plugins" Settings tab ## Migration Starting with pre-release 3.5 EDMC uses Python **3.7**. The first full release under Python 3.7 was 4.0.0.0. This is a brief outline of the steps required to migrate a plugin from earlier versions of EDMC: - Rename the function `plugin_start` to `plugin_start3(plugin_dir)`. Plugins without a `plugin_start3` function are listed as disabled on EDMC's "Plugins" tab and a message like "plugin SuperSpaceHelper needs migrating" appears in the log. Such plugins are also listed in a section "Plugins Without Python 3.x Support:" on the Settings > Plugins tab. - Check that callback functions `plugin_prefs`, `prefs_changed`, `journal_entry`, `dashboard_entry` and `cmdr_data` if used are declared with the correct number of arguments. Older versions of this app were tolerant of missing arguments in these function declarations. - Port the code to Python 3.7. The [2to3](https://docs.python.org/3/library/2to3.html) tool can automate much of this work. Depending on the complexity of the plugin it may be feasible to make it compatible with both EDMC 3.4 + Python 2.7 and EDMC 3.5 + Python 3.7. [Here's](https://python-future.org/compatible_idioms.html) a guide on writing Python 2/3 compatible code and [here's](https://github.com/Marginal/HabZone/commit/3c41cd41d5ad81ef36aab40e967e3baf77b4bd06) an example of the changes required for a simple plugin.