Coverage for src/su6/plugins.py: 100%
128 statements
« prev ^ index » next coverage.py v7.2.7, created at 2023-06-13 11:26 +0200
« prev ^ index » next coverage.py v7.2.7, created at 2023-06-13 11:26 +0200
1"""
2Provides a register decorator for third party plugins, and a `include_plugins` (used in cli.py) that loads them.
3"""
4import typing
5from dataclasses import dataclass
6from importlib.metadata import EntryPoint, entry_points
8from rich import print
9from typer import Typer
11from .core import (
12 AbstractConfig,
13 ApplicationState,
14 T_Command,
15 print_json,
16 run_tool,
17 state,
18 with_exit_code,
19)
21__all__ = ["register", "run_tool", "PluginConfig", "print", "print_json"]
24class PluginConfig(AbstractConfig):
25 """
26 Can be inherited in plugin to load in plugin-specific config.
28 The config class is a Singleton, which means multiple instances can be created, but they always have the same state.
30 Example:
31 @register()
32 class DemoConfig(PluginConfig):
33 required_arg: str
34 boolean_arg: bool
35 # ...
38 config = DemoConfig()
40 @register()
41 def with_arguments(required_arg: str, boolean_arg: bool = False) -> None:
42 config.update(required_arg=required_arg, boolean_arg=boolean_arg)
43 print(config)
44 """
46 extras: dict[str, typing.Any]
47 state: typing.Optional[ApplicationState] # only with @register(with_state=True) or after self.attach_state
49 def __init__(self, **kw: typing.Any) -> None:
50 """
51 Initial variables can be passed on instance creation.
52 """
53 super().__init__()
54 self.update(**kw)
55 self.extras = {}
57 def attach_extra(self, name: str, obj: typing.Any) -> None:
58 """
59 Add a non-annotated variable.
60 """
61 self.extras[name] = obj
63 def attach_state(self, global_state: ApplicationState) -> None:
64 """
65 Connect the global state to the plugin config.
66 """
67 self.state = global_state
68 self.attach_extra("state", global_state)
70 def _fields(self) -> typing.Generator[str, typing.Any, None]:
71 yield from self.__annotations__.keys()
72 if self.extras:
73 yield from self.extras.keys() # -> self.state in _values
75 def _get(self, key: str, strict: bool = True) -> typing.Any:
76 notfound = object()
78 value = getattr(self, key, notfound)
79 if value is not notfound:
80 return value
82 if self.extras:
83 value = self.extras.get(key, notfound)
84 if value is not notfound:
85 return value
87 if strict:
88 msg = f"{key} not found in `self {self.__class__.__name__}`"
89 if self.extras:
90 msg += f" or `extra's {self.extras.keys()}`"
91 raise KeyError(msg)
93 def _values(self) -> typing.Generator[typing.Any, typing.Any, None]:
94 yield from (self._get(k, False) for k in self._fields())
96 def __repr__(self) -> str:
97 """
98 Create a readable representation of this class with its data.
100 Stolen from dataclasses._repr_fn.
101 """
102 fields = self._fields()
103 values = self._values()
104 args = ", ".join([f"{f}={v!r}" for f, v in zip(fields, values)])
105 name = self.__class__.__qualname__
106 return f"{name}({args})"
108 def __str__(self) -> str:
109 """
110 Alias for repr.
111 """
112 return repr(self)
115T_PluginConfig = typing.Type[PluginConfig]
117U_Wrappable = typing.Union[T_PluginConfig, T_Command]
118T_Wrappable = typing.TypeVar("T_Wrappable", T_PluginConfig, T_Command)
121@dataclass()
122class Registration(typing.Generic[T_Wrappable]):
123 wrapped: T_Wrappable
124 args: tuple[typing.Any, ...]
125 kwargs: dict[str, typing.Any]
127 @property
128 def what(self) -> typing.Literal["command", "config"] | None:
129 if isinstance(self.wrapped, type) and issubclass(self.wrapped, PluginConfig):
130 return "config"
131 elif callable(self.wrapped):
132 return "command"
135# WeakValueDictionary() does not work since it removes the references too soon :(
136registrations: dict[int, Registration[T_PluginConfig] | Registration[T_Command]] = {}
139def _register(wrapped: T_Wrappable, *a: typing.Any, **kw: typing.Any) -> T_Wrappable:
140 registrations[id(wrapped)] = Registration(wrapped, a, kw)
141 return wrapped
144@typing.overload
145def register(wrappable: T_Wrappable, *a_outer: typing.Any, **kw_outer: typing.Any) -> T_Wrappable:
146 """
147 If wrappable is passed, it returns the same type.
149 @register
150 def func(): ...
152 -> register(func) is called
153 """
156@typing.overload
157def register(
158 wrappable: None = None, *a_outer: typing.Any, **kw_outer: typing.Any
159) -> typing.Callable[[T_Wrappable], T_Wrappable]:
160 """
161 If wrappable is None (empty), it returns a callback that will wrap the function later.
163 @register()
164 def func(): ...
166 -> register() is called
167 """
170def register(
171 wrappable: T_Wrappable = None, *a_outer: typing.Any, **kw_outer: typing.Any
172) -> T_Wrappable | typing.Callable[[T_Wrappable], T_Wrappable]:
173 """
174 Register a top-level Plugin command or a Plugin Config.
176 Examples:
177 @register() # () are optional, but you can add Typer keyword arguments if needed.
178 def command():
179 # 'su6 command' is now registered!
180 ...
182 @register() # () are optional, but extra keyword arguments can be passed to configure the config.
183 class MyConfig(PluginConfig):
184 property: str
185 """
187 def inner(func: T_Wrappable) -> T_Wrappable:
188 return _register(func, *a_outer, **kw_outer)
190 if wrappable:
191 return inner(wrappable)
192 else:
193 return inner
196T = typing.TypeVar("T")
199class BoundMethodOf(typing.Protocol[T]):
200 """
201 Protocol to define properties that a bound method has.
202 """
204 __self__: T
205 __name__: str # noqa: A003 - property does exist on the class
206 __doc__: typing.Optional[str] # noqa: A003 - property does exist on the class
208 def __call__(self, a: int) -> str: # pragma: no cover
209 """
210 Indicates this Protocol type can be called.
211 """
214Unbound = typing.Callable[..., typing.Any]
217def unbind(meth: BoundMethodOf[typing.Any] | Unbound) -> typing.Optional[Unbound]:
218 """
219 Extract the original function (which has a different id) from a class method.
220 """
221 return getattr(meth, "__func__", None)
224@dataclass()
225class PluginLoader:
226 app: Typer
227 with_exit_code: bool
229 def main(self) -> None:
230 """
231 Using importlib.metadata, discover available su6 plugins.
233 Example:
234 # pyproject.toml
235 # https://packaging.python.org/en/latest/guides/creating-and-discovering-plugins/#using-package-metadata
236 [project.entry-points."su6"]
237 demo = "su6_plugin_demo.cli" # <- CHANGE ME
238 """
239 discovered_plugins = entry_points(group="su6")
240 for plugin in discovered_plugins: # pragma: nocover
241 self._load_plugin(plugin)
243 self._cleanup()
245 def _cleanup(self) -> None:
246 # registrations.clear()
247 ...
249 def _load_plugin(self, plugin: EntryPoint) -> list[str]:
250 """
251 Look for typer instances and registered commands and configs in an Entrypoint.
253 [project.entry-points."su6"]
254 demo = "su6_plugin_demo.cli"
256 In this case, the entrypoint 'demo' is defined and points to the cli.py module,
257 which gets loaded with `plugin.load()` below.
258 """
259 result = []
260 plugin_module = plugin.load()
262 for item in dir(plugin_module):
263 if item.startswith("_"):
264 continue
266 possible_command = getattr(plugin_module, item)
268 # get method by id (in memory) or first unbind from class and then get by id
269 registration = registrations.get(id(possible_command)) or registrations.get(id(unbind(possible_command)))
271 if isinstance(possible_command, Typer):
272 result += self._add_subcommand(plugin.name, possible_command, plugin_module.__doc__)
273 elif registration and registration.what == "command":
274 result += self._add_command(plugin.name, typing.cast(Registration[T_Command], registration))
275 elif registration and registration.what == "config":
276 result += self._add_config(plugin.name, typing.cast(Registration[T_PluginConfig], registration))
277 # else: ignore
279 return result
281 def _add_command(self, _: str, registration: Registration[T_Command]) -> list[str]:
282 """
283 When a Command Registration is found, it is added to the top-level namespace.
284 """
285 if self.with_exit_code:
286 registration.wrapped = with_exit_code()(registration.wrapped)
287 # adding top-level commands
288 self.app.command(*registration.args, **registration.kwargs)(registration.wrapped)
289 return [f"command {_}"]
291 def _add_config(self, name: str, registration: Registration[T_PluginConfig]) -> list[str]:
292 """
293 When a Config Registration is found, the Singleton data is updated with config from pyproject.toml.
295 Example:
296 # pyproject.toml
297 [tool.su6.demo]
298 boolean-arg = true
299 optional-with-default = "overridden"
301 [tool.su6.demo.extra]
302 more = true
303 """
304 key = registration.kwargs.pop("config_key", name)
306 cls = registration.wrapped
307 inst = cls()
309 if registration.kwargs.pop("with_state", False):
310 inst.attach_state(state)
312 if registration.kwargs.pop("strict", True) is False:
313 inst._strict = False
315 state.attach_plugin_config(key, inst)
316 return [f"config {name}"]
318 def _add_subcommand(self, name: str, subapp: Typer, doc: str) -> list[str]:
319 self.app.add_typer(subapp, name=name, help=doc)
320 return [f"subcommand {name}"]
323def include_plugins(app: Typer, _with_exit_code: bool = True) -> None:
324 """
325 Discover plugins using discover_plugins and add them to either global namespace or as a subcommand.
327 Args:
328 app: the top-level Typer app to append commands to
329 state: top-level application state
330 _with_exit_code: should the @with_exit_code decorator be applied to the return value of the command?
331 """
332 loader = PluginLoader(app, _with_exit_code)
333 loader.main()
336# todo:
337# - add to 'all'
338# - add to 'fix'