Coverage for src/su6/plugins.py: 100%

128 statements  

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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 

7 

8from rich import print 

9from typer import Typer 

10 

11from .core import ( 

12 AbstractConfig, 

13 ApplicationState, 

14 T_Command, 

15 print_json, 

16 run_tool, 

17 state, 

18 with_exit_code, 

19) 

20 

21__all__ = ["register", "run_tool", "PluginConfig", "print", "print_json"] 

22 

23 

24class PluginConfig(AbstractConfig): 

25 """ 

26 Can be inherited in plugin to load in plugin-specific config. 

27 

28 The config class is a Singleton, which means multiple instances can be created, but they always have the same state. 

29 

30 Example: 

31 @register() 

32 class DemoConfig(PluginConfig): 

33 required_arg: str 

34 boolean_arg: bool 

35 # ... 

36 

37 

38 config = DemoConfig() 

39 

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 """ 

45 

46 extras: dict[str, typing.Any] 

47 state: typing.Optional[ApplicationState] # only with @register(with_state=True) or after self.attach_state 

48 

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 = {} 

56 

57 def attach_extra(self, name: str, obj: typing.Any) -> None: 

58 """ 

59 Add a non-annotated variable. 

60 """ 

61 self.extras[name] = obj 

62 

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) 

69 

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 

74 

75 def _get(self, key: str, strict: bool = True) -> typing.Any: 

76 notfound = object() 

77 

78 value = getattr(self, key, notfound) 

79 if value is not notfound: 

80 return value 

81 

82 if self.extras: 

83 value = self.extras.get(key, notfound) 

84 if value is not notfound: 

85 return value 

86 

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) 

92 

93 def _values(self) -> typing.Generator[typing.Any, typing.Any, None]: 

94 yield from (self._get(k, False) for k in self._fields()) 

95 

96 def __repr__(self) -> str: 

97 """ 

98 Create a readable representation of this class with its data. 

99 

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})" 

107 

108 def __str__(self) -> str: 

109 """ 

110 Alias for repr. 

111 """ 

112 return repr(self) 

113 

114 

115T_PluginConfig = typing.Type[PluginConfig] 

116 

117U_Wrappable = typing.Union[T_PluginConfig, T_Command] 

118T_Wrappable = typing.TypeVar("T_Wrappable", T_PluginConfig, T_Command) 

119 

120 

121@dataclass() 

122class Registration(typing.Generic[T_Wrappable]): 

123 wrapped: T_Wrappable 

124 args: tuple[typing.Any, ...] 

125 kwargs: dict[str, typing.Any] 

126 

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" 

133 

134 

135# WeakValueDictionary() does not work since it removes the references too soon :( 

136registrations: dict[int, Registration[T_PluginConfig] | Registration[T_Command]] = {} 

137 

138 

139def _register(wrapped: T_Wrappable, *a: typing.Any, **kw: typing.Any) -> T_Wrappable: 

140 registrations[id(wrapped)] = Registration(wrapped, a, kw) 

141 return wrapped 

142 

143 

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. 

148 

149 @register 

150 def func(): ... 

151 

152 -> register(func) is called 

153 """ 

154 

155 

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. 

162 

163 @register() 

164 def func(): ... 

165 

166 -> register() is called 

167 """ 

168 

169 

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. 

175 

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 ... 

181 

182 @register() # () are optional, but extra keyword arguments can be passed to configure the config. 

183 class MyConfig(PluginConfig): 

184 property: str 

185 """ 

186 

187 def inner(func: T_Wrappable) -> T_Wrappable: 

188 return _register(func, *a_outer, **kw_outer) 

189 

190 if wrappable: 

191 return inner(wrappable) 

192 else: 

193 return inner 

194 

195 

196T = typing.TypeVar("T") 

197 

198 

199class BoundMethodOf(typing.Protocol[T]): 

200 """ 

201 Protocol to define properties that a bound method has. 

202 """ 

203 

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 

207 

208 def __call__(self, a: int) -> str: # pragma: no cover 

209 """ 

210 Indicates this Protocol type can be called. 

211 """ 

212 

213 

214Unbound = typing.Callable[..., typing.Any] 

215 

216 

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) 

222 

223 

224@dataclass() 

225class PluginLoader: 

226 app: Typer 

227 with_exit_code: bool 

228 

229 def main(self) -> None: 

230 """ 

231 Using importlib.metadata, discover available su6 plugins. 

232 

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) 

242 

243 self._cleanup() 

244 

245 def _cleanup(self) -> None: 

246 # registrations.clear() 

247 ... 

248 

249 def _load_plugin(self, plugin: EntryPoint) -> list[str]: 

250 """ 

251 Look for typer instances and registered commands and configs in an Entrypoint. 

252 

253 [project.entry-points."su6"] 

254 demo = "su6_plugin_demo.cli" 

255 

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() 

261 

262 for item in dir(plugin_module): 

263 if item.startswith("_"): 

264 continue 

265 

266 possible_command = getattr(plugin_module, item) 

267 

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))) 

270 

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 

278 

279 return result 

280 

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 {_}"] 

290 

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. 

294 

295 Example: 

296 # pyproject.toml 

297 [tool.su6.demo] 

298 boolean-arg = true 

299 optional-with-default = "overridden" 

300 

301 [tool.su6.demo.extra] 

302 more = true 

303 """ 

304 key = registration.kwargs.pop("config_key", name) 

305 

306 cls = registration.wrapped 

307 inst = cls() 

308 

309 if registration.kwargs.pop("with_state", False): 

310 inst.attach_state(state) 

311 

312 if registration.kwargs.pop("strict", True) is False: 

313 inst._strict = False 

314 

315 state.attach_plugin_config(key, inst) 

316 return [f"config {name}"] 

317 

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}"] 

321 

322 

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. 

326 

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() 

334 

335 

336# todo: 

337# - add to 'all' 

338# - add to 'fix'