feat(plugins): Identify plugins by id, migrations must be provided at defined location, add utils for plugin functions

README.md

@@ -44,11 +44,12 @@ If not you need to create user and database manually do (or similar on Windows):
     ) | sudo mysql
 
 Then you can install the database tables, this will update all tables from core + all enabled plugins.
+*Hint:* The same command can be later used to upgrade the database after plugins or core are updated.
 
     $ flaschengeist db upgrade heads
 
 ## Plugins
-To only upgrade one plugin:
+To only upgrade one plugin (for example the `events` plugin):
 
     $ flaschengeist db upgrade events@head
 

flaschengeist/__init__.py

@@ -1,11 +1,9 @@
 """Flaschengeist"""
 import logging
 import pkg_resources
-from pathlib import Path
 from werkzeug.local import LocalProxy
 
 __version__ = pkg_resources.get_distribution("flaschengeist").version
-_module_path = Path(__file__).parent
 __pdoc__ = {}
 
 logger: logging.Logger = LocalProxy(lambda: logging.getLogger(__name__))

flaschengeist/app.py

@@ -1,18 +1,18 @@
 import enum
 
-import pkg_resources
+from flask import Flask
-from flask import Flask, current_app
 from flask_cors import CORS
 from datetime import datetime, date
 from flask.json import JSONEncoder, jsonify
 from sqlalchemy.exc import OperationalError
 from werkzeug.exceptions import HTTPException
 
+from flaschengeist.utils.plugin import get_plugins
+
 from . import logger
-from .plugins import AuthPlugin
+from .plugins import Plugin
-from flaschengeist.config import config, configure_app
+from .config import config, configure_app
-from flaschengeist.controller import roleController
+from .utils.hook import Hook
-from flaschengeist.utils.hook import Hook
 
 
 class CustomJSONEncoder(JSONEncoder):
@@ -37,64 +37,35 @@ class CustomJSONEncoder(JSONEncoder):
 
 
 @Hook("plugins.loaded")
-def __load_plugins(app):
+def load_plugins(app: Flask):
-    logger.debug("Search for plugins")
+    def load_plugin(cls: type[Plugin]):
-
+        logger.debug(f"Load plugin {cls.id}")
-    app.config["FG_PLUGINS"] = {}
+        # Initialize plugin with config section
-    for entry_point in pkg_resources.iter_entry_points("flaschengeist.plugins"):
+        plugin = cls(config.get(plugin_class.id, config.get(plugin_class.id.split(".")[-1], {})))
-        logger.debug(f"Found plugin: >{entry_point.name}<")
+        # Register blueprint if provided
-
+        if plugin.blueprint is not None:
-        if entry_point.name == config["FLASCHENGEIST"]["auth"] or (
-            entry_point.name in config and config[entry_point.name].get("enabled", False)
-        ):
-            logger.debug(f"Load plugin {entry_point.name}")
-            try:
-                plugin = entry_point.load()
-                if not hasattr(plugin, "name"):
-                    setattr(plugin, "name", entry_point.name)
-                plugin = plugin(config.get(entry_point.name, {}))
-                if hasattr(plugin, "blueprint") and plugin.blueprint is not None:
             app.register_blueprint(plugin.blueprint)
-            except:
+        # Save plugin application context
-                logger.error(
+        app.config.setdefault("FG_PLUGINS", {})[plugin.id] = plugin
-                    f"Plugin {entry_point.name} was enabled, but could not be loaded due to an error.",
+        return plugin
-                    exc_info=True,
+
-                )
+    for plugin_class in get_plugins():
-                continue
+        names = [plugin_class.id, plugin_class.id.split(".")[-1]]
-            if isinstance(plugin, AuthPlugin):
+        if config["FLASCHENGEIST"]["auth"] in names:
-                if entry_point.name != config["FLASCHENGEIST"]["auth"]:
+            # Load authentification plugin
-                    logger.debug(f"Unload not configured AuthPlugin {entry_point.name}")
+            app.config["FG_AUTH_BACKEND"] = load_plugin(plugin_class)
-                    del plugin
+            logger.info(f"Using authentication plugin: {plugin_class.id}")
-                    continue
+        elif any([i in config and config[i].get("enabled", False) for i in names]):
+            # Load all other enabled plugins
+            load_plugin(plugin_class)
+            logger.info(f"Using plugin: {plugin_class.id}")
         else:
-                    logger.info(f"Using authentication plugin: {entry_point.name}")
+            logger.debug(f"Skip disabled plugin {plugin_class.id}")
-                    app.config["FG_AUTH_BACKEND"] = plugin
-            else:
-                logger.info(f"Using plugin: {entry_point.name}")
-            app.config["FG_PLUGINS"][entry_point.name] = plugin
-        else:
-            logger.debug(f"Skip disabled plugin {entry_point.name}")
     if "FG_AUTH_BACKEND" not in app.config:
-        logger.error("No authentication plugin configured or authentication plugin not found")
+        logger.fatal("No authentication plugin configured or authentication plugin not found")
         raise RuntimeError("No authentication plugin configured or authentication plugin not found")
 
 
-@Hook("plugins.installed")
-def install_all():
-    from flaschengeist.database import db
-
-    db.create_all()
-    db.session.commit()
-    for name, plugin in current_app.config["FG_PLUGINS"].items():
-        if not plugin:
-            logger.debug(f"Skip disabled plugin: {name}")
-            continue
-        logger.info(f"Install plugin {name}")
-        plugin.install()
-        if plugin.permissions:
-            roleController.create_permissions(plugin.permissions)
-
-
 def create_app(test_config=None, cli=False):
     app = Flask(__name__)
     app.json_encoder = CustomJSONEncoder
@@ -106,7 +77,7 @@ def create_app(test_config=None, cli=False):
         configure_app(app, test_config, cli)
         db.init_app(app)
         migrate.init_app(app, db, compare_type=True)
-        __load_plugins(app)
+        load_plugins(app)
 
     @app.route("/", methods=["GET"])
     def __get_state():

flaschengeist/config.py

@@ -5,7 +5,7 @@ import collections.abc
 
 from pathlib import Path
 from werkzeug.middleware.proxy_fix import ProxyFix
-from flaschengeist import _module_path, logger
+from flaschengeist import logger
 
 
 # Default config:
@@ -23,7 +23,7 @@ def update_dict(d, u):
 
 def read_configuration(test_config):
     global config
-    paths = [_module_path]
+    paths = [Path(__file__).parent]
 
     if not test_config:
         paths.append(Path.home() / ".config")
@@ -44,7 +44,7 @@ def read_configuration(test_config):
 def configure_logger(cli=False):
     global config
     # Read default config
-    logger_config = toml.load(_module_path / "logging.toml")
+    logger_config = toml.load(Path(__file__).parent / "logging.toml")
 
     if "LOGGING" in config:
         # Override with user config

flaschengeist/database.py

@@ -22,8 +22,18 @@ migrate = Migrate()
 
 @migrate.configure
 def configure_alembic(config):
+    """Alembic configuration hook
+
+    Inject all migrations paths into the ``version_locations`` config option.
+    This includes even disabled plugins, as simply disabling a plugin without
+    uninstall can break the alembic version management.
+    """
+    import inspect, pathlib
+    from flaschengeist.utils.plugin import get_plugins
+
     # Load migration paths from plugins
-    migrations = [str(p.migrations_path) for p in current_app.config["FG_PLUGINS"].values() if p and p.migrations_path]
+    migrations = [(pathlib.Path(inspect.getfile(p)).parent / "migrations") for p in get_plugins()]
+    migrations = [str(m.resolve()) for m in migrations if m.exists()]
     if len(migrations) > 0:
         # Get configured paths
         paths = config.get_main_option("version_locations")

flaschengeist/plugins/__init__.py

@@ -1,81 +1,142 @@
-import sqlalchemy
+"""Flaschengeist Plugins
-import pkg_resources
-from werkzeug.datastructures import FileStorage
-from werkzeug.exceptions import MethodNotAllowed, NotFound
-from flaschengeist.controller import imageController
 
-from flaschengeist.database import db
+## Custom database tables
-from flaschengeist.models.notification import Notification
+
-from flaschengeist.models.user import _Avatar, User
+You can add tables by declaring them using the SQLAlchemy syntax,
-from flaschengeist.models.setting import _PluginSetting
+then use Alembic to generate migrations for your tables.
+This allows Flaschengeist to proper up- or downgrade the
+database tables if an user updates your plugin.
+
+migrations have to be provided in a directory called `migrations`
+next to your plugin. E.G.
+
+    myplugin
+        - __init__.py
+        - other/
+            - ...
+        - migrations/
+
+## Useful Hooks
+There are some predefined hooks, which might get handy for you.
+
+For more information, please refer to
+- `flaschengeist.utils.hook.HookBefore` and
+- `flaschengeist.utils.hook.HookAfter`
+"""
+
+import sqlalchemy
+from werkzeug.exceptions import MethodNotAllowed, NotFound
 from flaschengeist.utils.hook import HookBefore, HookAfter
 
-plugins_installed = HookAfter("plugins.installed")
+__all__ = [
-"""Hook decorator for when all plugins are installed
+    "plugins_installed",
-    Possible use case would be to populate the database with some presets.
+    "plugins_loaded",
+    "before_delete_user",
+    "before_role_updated",
+    "before_update_user",
+    "after_role_updated",
+    "Plugin",
+    "AuthPlugin",
+]
 
-    Args:
+# Documentation hacks, see https://github.com/mitmproxy/pdoc/issues/320
-        hook_result: void (kwargs)
+plugins_installed = HookAfter("plugins.installed")
+plugins_installed.__doc__ = """Hook decorator for when all plugins are installed
+
+Possible use case would be to populate the database with some presets.
 """
+
 plugins_loaded = HookAfter("plugins.loaded")
-"""Hook decorator for when all plugins are loaded
+plugins_loaded.__doc__ = """Hook decorator for when all plugins are loaded
+
 Possible use case would be to check if a specific other plugin is loaded and change own behavior
 
-    Args:
+Passed args:
-        app: Current flask app instance (args)
+    - *app:* Current flask app instance (args)
-        hook_result: void (kwargs)
 """
+
 before_role_updated = HookBefore("update_role")
-"""Hook decorator for when roles are modified
+before_role_updated.__doc__ = """Hook decorator for when roles are modified
-Args:
+    
-    role: Role object to modify
+Passed args:
-    new_name: New name if the name was changed (None if delete)
+    - *role:* `flaschengeist.models.user.Role` to modify
+    - *new_name:* New name if the name was changed (*None* if delete)
 """
+
 after_role_updated = HookAfter("update_role")
-"""Hook decorator for when roles are modified
+after_role_updated.__doc__ = """Hook decorator for when roles are modified
-Args:
+
-    role: Role object containing the modified role
+Passed args:
-    new_name: New name if the name was changed (None if deleted)
+    - *role:* modified `flaschengeist.models.user.Role`
+    - *new_name:* New name if the name was changed (*None* if deleted)
 """
+
 before_update_user = HookBefore("update_user")
-"""Hook decorator, when ever an user update is done, this is called before.
+before_update_user.__doc__ = """Hook decorator, when ever an user update is done, this is called before.
-Args:
+
-    user: User object
+Passed args:
+    - *user:* `flaschengeist.models.user.User` object
 """
+
 before_delete_user = HookBefore("delete_user")
-"""Hook decorator,this is called before an user gets deleted.
+before_delete_user.__doc__ = """Hook decorator,this is called before an user gets deleted.
-Args:
+
-    user: User object
+Passed args:
+    - *user:* `flaschengeist.models.user.User` object
 """
 
 
 class Plugin:
     """Base class for all Plugins
-    If your class uses custom models add a static property called ``models``"""
 
-    blueprint = None  # You have to override
+    All plugins must be derived from this class.
+    There are some static properties a plugin must provide,
+    and some properties a plugin can provide if you might want
+    to use more functionality.
+
+    Required:
+        - *id*: Unique identifier of your plugin
+
+    Optional:
+        - *blueprint*: `flask.Blueprint` providing your routes
+        - *permissions*: List of your custom permissions
+        - *models*: Your models, used for API export
+        - *version*: Version of your plugin, can also be guessed by Flaschengeist
+    """
+
+    id: str = None
+    """Override with the unique ID of the plugin
+    
+    Hint: Use a fully qualified name like "dev.flaschengeist.plugin"
+    """
+
+    blueprint = None
     """Override with a `flask.blueprint` if the plugin uses custom routes"""
-    permissions = []  # You have to override
+
+    permissions: list[str] = []  # You have to override
     """Override to add custom permissions used by the plugin
     
     A good style is to name the permissions with a prefix related to the plugin name,
     to prevent clashes with other plugins. E. g. instead of *delete* use *plugin_delete*.
     """
-    id = "dev.flaschengeist.plugin"  # You have to override
+
-    """Override with the unique ID of the plugin (Hint: FQN)"""
+    models = None
-    name = "plugin"  # You have to override
+    """Override with models module
-    """Override with human readable name of the plugin"""
+    
-    models = None  # You have to override
+    Used for API export, has to be a static property
-    """Override with models module"""
+    """
-    migrations_path = None  # Override this with the location of your db migrations directory
+
-    """Override with path to migration files, if custome db tables are used"""
+    version = None
+    """Override with a custom version, optional
+    
+    If not set, the version is guessed from the package / distribution
+    """
 
     def __init__(self, config=None):
         """Constructor called by create_app
         Args:
             config: Dict configuration containing the plugin section
         """
-        self.version = pkg_resources.get_distribution(self.__module__.split(".")[0]).version
 
     def install(self):
         """Installation routine
@@ -84,6 +145,17 @@ class Plugin:
         """
         pass
 
+    def uninstall(self):
+        """Uninstall routine
+
+        If the plugin has custom database tables, make sure to remove them.
+        This can be either done by downgrading the plugin *head* to the *base*.
+        Or use custom migrations for the uninstall and *stamp* some version.
+
+        Is always called with Flask application context.
+        """
+        pass
+
     def get_setting(self, name: str, **kwargs):
         """Get plugin setting from database
 
@@ -95,6 +167,8 @@ class Plugin:
         Raises:
             `KeyError` if no such setting exists in the database
         """
+        from flaschengeist.models.setting import _PluginSetting
+
         try:
             setting = (
                 _PluginSetting.query.filter(_PluginSetting.plugin == self.name)
@@ -115,6 +189,9 @@ class Plugin:
             name: String identifying the setting
             value: Value to be stored
         """
+        from flaschengeist.models.setting import _PluginSetting
+        from flaschengeist.database import db
+
         setting = (
             _PluginSetting.query.filter(_PluginSetting.plugin == self.name)
             .filter(_PluginSetting.name == name)
@@ -141,6 +218,9 @@ class Plugin:
 
         Hint: use the data for frontend actions.
         """
+        from flaschengeist.models.notification import Notification
+        from flaschengeist.database import db
+
         if not user.deleted:
             n = Notification(text=text, data=data, plugin=self.id, user_=user)
             db.session.add(n)
@@ -157,6 +237,11 @@ class Plugin:
 
 
 class AuthPlugin(Plugin):
+    """Base class for all authentification plugins
+
+    See also `Plugin`
+    """
+
     def login(self, user, pw):
         """Login routine, MUST BE IMPLEMENTED!
 
@@ -219,7 +304,7 @@ class AuthPlugin(Plugin):
         """
         raise MethodNotAllowed
 
-    def get_avatar(self, user: User) -> _Avatar:
+    def get_avatar(self, user):
         """Retrieve avatar for given user (if supported by auth backend)
 
         Default behavior is to use native Image objects,
@@ -233,21 +318,23 @@ class AuthPlugin(Plugin):
         """
         raise NotFound
 
-    def set_avatar(self, user: User, file: FileStorage):
+    def set_avatar(self, user, file):
         """Set the avatar for given user (if supported by auth backend)
 
         Default behavior is to use native Image objects stored on the Flaschengeist server
 
         Args:
             user: User to set the avatar for
-            file: FileStorage object uploaded by the user
+            file: `werkzeug.datastructures.FileStorage` uploaded by the user
         Raises:
             MethodNotAllowed: If not supported by Backend
             Any valid HTTP exception
         """
+        from flaschengeist.controller import imageController
+
         user.avatar_ = imageController.upload_image(file)
 
-    def delete_avatar(self, user: User):
+    def delete_avatar(self, user):
         """Delete the avatar for given user (if supported by auth backend)
 
         Default behavior is to use the imageController and native Image objects.

flaschengeist/plugins/auth/__init__.py

@@ -13,8 +13,8 @@ from flaschengeist.controller import sessionController, userController
 
 
 class AuthRoutePlugin(Plugin):
-    name = "auth"
+    id = "dev.flaschengeist.auth"
-    blueprint = Blueprint(name, __name__)
+    blueprint = Blueprint("auth", __name__)
 
 
 @AuthRoutePlugin.blueprint.route("/auth", methods=["POST"])

flaschengeist/plugins/auth_ldap/__init__.py

@@ -17,6 +17,8 @@ from flaschengeist.plugins import AuthPlugin, before_role_updated
 
 
 class AuthLDAP(AuthPlugin):
+    id = "auth_ldap"
+
     def __init__(self, config):
         super().__init__()
         app.config.update(

flaschengeist/plugins/auth_plain/__init__.py

@@ -14,6 +14,8 @@ from flaschengeist import logger
 
 
 class AuthPlain(AuthPlugin):
+    id = "auth_plain"
+
     def install(self):
         plugins_installed(self.post_install)
 

flaschengeist/plugins/balance/__init__.py

@@ -57,9 +57,10 @@ def service_debit():
 
 
 class BalancePlugin(Plugin):
-    name = "balance"
+    """Balance Plugin"""
+
     id = "dev.flaschengeist.balance"
-    blueprint = Blueprint(name, __name__)
+    blueprint = Blueprint("balance", __name__)
     permissions = permissions.permissions
     plugin: "BalancePlugin" = LocalProxy(lambda: current_app.config["FG_PLUGINS"][BalancePlugin.name])
     models = models

flaschengeist/plugins/balance/routes.py

@@ -131,7 +131,7 @@ def get_balance(userid, current_session: Session):
 
     Route: ``/users/<userid>/balance`` | Method: ``GET``
 
-    GET-parameters: ```{from?: string, to?: string}```
+    GET-parameters: ``{from?: string, to?: string}``
 
     Args:
         userid: Userid of user to get balance from
@@ -170,7 +170,7 @@ def get_transactions(userid, current_session: Session):
 
     Route: ``/users/<userid>/balance/transactions`` | Method: ``GET``
 
-    GET-parameters: ```{from?: string, to?: string, limit?: int, offset?: int}```
+    GET-parameters: ``{from?: string, to?: string, limit?: int, offset?: int}``
 
     Args:
         userid: Userid of user to get transactions from

flaschengeist/plugins/message_mail.py

@@ -12,6 +12,8 @@ from . import Plugin
 
 
 class MailMessagePlugin(Plugin):
+    id = "dev.flaschengeist.mail_plugin"
+
     def __init__(self, config):
         super().__init__()
         self.server = config["SERVER"]

flaschengeist/plugins/pricelist/__init__.py

@@ -17,9 +17,9 @@ from . import pricelist_controller, permissions
 
 
 class PriceListPlugin(Plugin):
-    name = "pricelist"
+    id = "dev.flaschengeist.pricelist"
     permissions = permissions.permissions
-    blueprint = Blueprint(name, __name__, url_prefix="/pricelist")
+    blueprint = Blueprint("pricelist", __name__, url_prefix="/pricelist")
     plugin = LocalProxy(lambda: current_app.config["FG_PLUGINS"][PriceListPlugin.name])
     models = models
 

flaschengeist/plugins/roles/__init__.py

@@ -16,8 +16,8 @@ from . import permissions
 
 
 class RolesPlugin(Plugin):
-    name = "roles"
+    id = "dev.flaschengeist.roles"
-    blueprint = Blueprint(name, __name__)
+    blueprint = Blueprint("roles", __name__)
     permissions = permissions.permissions
 
 

flaschengeist/plugins/users/__init__.py

@@ -18,8 +18,8 @@ from flaschengeist.utils.datetime import from_iso_format
 
 
 class UsersPlugin(Plugin):
-    name = "users"
+    id = "dev.flaschengeist.users"
-    blueprint = Blueprint(name, __name__)
+    blueprint = Blueprint("users", __name__)
     permissions = permissions.permissions
 
 

flaschengeist/utils/hook.py

@@ -7,6 +7,7 @@ _hooks_after = {}
 
 def Hook(function=None, id=None):
     """Hook decorator
+
     Use to decorate functions as hooks, so plugins can hook up their custom functions.
     """
     # `id` passed as `arg` not `kwarg`
@@ -38,8 +39,10 @@ def Hook(function=None, id=None):
 
 def HookBefore(id: str):
     """Decorator for functions to be called before a Hook-Function is called
+
     The hooked up function must accept the same arguments as the function hooked onto,
     as the functions are called with the same arguments.
+
     Hint: This enables you to modify the arguments!
     """
     if not id or not isinstance(id, str):
@@ -54,9 +57,18 @@ def HookBefore(id: str):
 
 def HookAfter(id: str):
     """Decorator for functions to be called after a Hook-Function is called
+
     As with the HookBefore, the hooked up function must accept the same
     arguments as the function hooked onto, but also receives a
     `hook_result` kwarg containing the result of the function.
+
+    Example:
+        ```py
+        @HookAfter("some.id")
+        def my_func(hook_result):
+            # This function is executed after the function registered with "some.id"
+            print(hook_result)  # This is the result of the function
+        ```
     """
 
     if not id or not isinstance(id, str):

flaschengeist/utils/plugin.py

@@ -0,0 +1,46 @@
+"""Plugin utils
+
+Utilities for handling Flaschengeist plugins
+"""
+
+import pkg_resources
+from flaschengeist import logger
+from flaschengeist.plugins import Plugin
+
+
+def get_plugins() -> list[type[Plugin]]:
+    """Get all installed plugins for Flaschengeist
+
+    Returns:
+        list of classes implementing `flaschengeist.plugins.Plugin`
+    """
+    logger.debug("Search for plugins")
+
+    plugins = []
+    for entry_point in pkg_resources.iter_entry_points("flaschengeist.plugins"):
+        try:
+            logger.debug(f"Found plugin: >{entry_point.name}<")
+            plugin_class = entry_point.load()
+            if issubclass(plugin_class, Plugin):
+                plugins.append(plugin_class)
+        except TypeError:
+            logger.error(f"Invalid entry point for plugin {entry_point.name} found.")
+    return plugins
+
+
+def plugin_version(plugin: type[Plugin]) -> str:
+    """Get version of plugin
+
+    Returns the version of a plugin, if plugin does not set the
+    version property, the version of the package providing the
+    plugin is taken.
+
+    Args:
+        plugin: Plugin or Plugin class
+
+    Returns:
+        Version as string
+    """
+    if plugin.version:
+        return plugin.version
+    return pkg_resources.get_distribution(plugin.__module__.split(".", 1)[0]).version