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Diffstat (limited to 'venv/lib/python3.8/site-packages/flask/sansio/blueprints.py')
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1 files changed, 632 insertions, 0 deletions
diff --git a/venv/lib/python3.8/site-packages/flask/sansio/blueprints.py b/venv/lib/python3.8/site-packages/flask/sansio/blueprints.py new file mode 100644 index 0000000..4f912cc --- /dev/null +++ b/venv/lib/python3.8/site-packages/flask/sansio/blueprints.py @@ -0,0 +1,632 @@ +from __future__ import annotations + +import os +import typing as t +from collections import defaultdict +from functools import update_wrapper + +from .. import typing as ft +from .scaffold import _endpoint_from_view_func +from .scaffold import _sentinel +from .scaffold import Scaffold +from .scaffold import setupmethod + +if t.TYPE_CHECKING: # pragma: no cover + from .app import App + +DeferredSetupFunction = t.Callable[["BlueprintSetupState"], None] +T_after_request = t.TypeVar("T_after_request", bound=ft.AfterRequestCallable[t.Any]) +T_before_request = t.TypeVar("T_before_request", bound=ft.BeforeRequestCallable) +T_error_handler = t.TypeVar("T_error_handler", bound=ft.ErrorHandlerCallable) +T_teardown = t.TypeVar("T_teardown", bound=ft.TeardownCallable) +T_template_context_processor = t.TypeVar( + "T_template_context_processor", bound=ft.TemplateContextProcessorCallable +) +T_template_filter = t.TypeVar("T_template_filter", bound=ft.TemplateFilterCallable) +T_template_global = t.TypeVar("T_template_global", bound=ft.TemplateGlobalCallable) +T_template_test = t.TypeVar("T_template_test", bound=ft.TemplateTestCallable) +T_url_defaults = t.TypeVar("T_url_defaults", bound=ft.URLDefaultCallable) +T_url_value_preprocessor = t.TypeVar( + "T_url_value_preprocessor", bound=ft.URLValuePreprocessorCallable +) + + +class BlueprintSetupState: + """Temporary holder object for registering a blueprint with the + application. An instance of this class is created by the + :meth:`~flask.Blueprint.make_setup_state` method and later passed + to all register callback functions. + """ + + def __init__( + self, + blueprint: Blueprint, + app: App, + options: t.Any, + first_registration: bool, + ) -> None: + #: a reference to the current application + self.app = app + + #: a reference to the blueprint that created this setup state. + self.blueprint = blueprint + + #: a dictionary with all options that were passed to the + #: :meth:`~flask.Flask.register_blueprint` method. + self.options = options + + #: as blueprints can be registered multiple times with the + #: application and not everything wants to be registered + #: multiple times on it, this attribute can be used to figure + #: out if the blueprint was registered in the past already. + self.first_registration = first_registration + + subdomain = self.options.get("subdomain") + if subdomain is None: + subdomain = self.blueprint.subdomain + + #: The subdomain that the blueprint should be active for, ``None`` + #: otherwise. + self.subdomain = subdomain + + url_prefix = self.options.get("url_prefix") + if url_prefix is None: + url_prefix = self.blueprint.url_prefix + #: The prefix that should be used for all URLs defined on the + #: blueprint. + self.url_prefix = url_prefix + + self.name = self.options.get("name", blueprint.name) + self.name_prefix = self.options.get("name_prefix", "") + + #: A dictionary with URL defaults that is added to each and every + #: URL that was defined with the blueprint. + self.url_defaults = dict(self.blueprint.url_values_defaults) + self.url_defaults.update(self.options.get("url_defaults", ())) + + def add_url_rule( + self, + rule: str, + endpoint: str | None = None, + view_func: ft.RouteCallable | None = None, + **options: t.Any, + ) -> None: + """A helper method to register a rule (and optionally a view function) + to the application. The endpoint is automatically prefixed with the + blueprint's name. + """ + if self.url_prefix is not None: + if rule: + rule = "/".join((self.url_prefix.rstrip("/"), rule.lstrip("/"))) + else: + rule = self.url_prefix + options.setdefault("subdomain", self.subdomain) + if endpoint is None: + endpoint = _endpoint_from_view_func(view_func) # type: ignore + defaults = self.url_defaults + if "defaults" in options: + defaults = dict(defaults, **options.pop("defaults")) + + self.app.add_url_rule( + rule, + f"{self.name_prefix}.{self.name}.{endpoint}".lstrip("."), + view_func, + defaults=defaults, + **options, + ) + + +class Blueprint(Scaffold): + """Represents a blueprint, a collection of routes and other + app-related functions that can be registered on a real application + later. + + A blueprint is an object that allows defining application functions + without requiring an application object ahead of time. It uses the + same decorators as :class:`~flask.Flask`, but defers the need for an + application by recording them for later registration. + + Decorating a function with a blueprint creates a deferred function + that is called with :class:`~flask.blueprints.BlueprintSetupState` + when the blueprint is registered on an application. + + See :doc:`/blueprints` for more information. + + :param name: The name of the blueprint. Will be prepended to each + endpoint name. + :param import_name: The name of the blueprint package, usually + ``__name__``. This helps locate the ``root_path`` for the + blueprint. + :param static_folder: A folder with static files that should be + served by the blueprint's static route. The path is relative to + the blueprint's root path. Blueprint static files are disabled + by default. + :param static_url_path: The url to serve static files from. + Defaults to ``static_folder``. If the blueprint does not have + a ``url_prefix``, the app's static route will take precedence, + and the blueprint's static files won't be accessible. + :param template_folder: A folder with templates that should be added + to the app's template search path. The path is relative to the + blueprint's root path. Blueprint templates are disabled by + default. Blueprint templates have a lower precedence than those + in the app's templates folder. + :param url_prefix: A path to prepend to all of the blueprint's URLs, + to make them distinct from the rest of the app's routes. + :param subdomain: A subdomain that blueprint routes will match on by + default. + :param url_defaults: A dict of default values that blueprint routes + will receive by default. + :param root_path: By default, the blueprint will automatically set + this based on ``import_name``. In certain situations this + automatic detection can fail, so the path can be specified + manually instead. + + .. versionchanged:: 1.1.0 + Blueprints have a ``cli`` group to register nested CLI commands. + The ``cli_group`` parameter controls the name of the group under + the ``flask`` command. + + .. versionadded:: 0.7 + """ + + _got_registered_once = False + + def __init__( + self, + name: str, + import_name: str, + static_folder: str | os.PathLike[str] | None = None, + static_url_path: str | None = None, + template_folder: str | os.PathLike[str] | None = None, + url_prefix: str | None = None, + subdomain: str | None = None, + url_defaults: dict[str, t.Any] | None = None, + root_path: str | None = None, + cli_group: str | None = _sentinel, # type: ignore[assignment] + ): + super().__init__( + import_name=import_name, + static_folder=static_folder, + static_url_path=static_url_path, + template_folder=template_folder, + root_path=root_path, + ) + + if not name: + raise ValueError("'name' may not be empty.") + + if "." in name: + raise ValueError("'name' may not contain a dot '.' character.") + + self.name = name + self.url_prefix = url_prefix + self.subdomain = subdomain + self.deferred_functions: list[DeferredSetupFunction] = [] + + if url_defaults is None: + url_defaults = {} + + self.url_values_defaults = url_defaults + self.cli_group = cli_group + self._blueprints: list[tuple[Blueprint, dict[str, t.Any]]] = [] + + def _check_setup_finished(self, f_name: str) -> None: + if self._got_registered_once: + raise AssertionError( + f"The setup method '{f_name}' can no longer be called on the blueprint" + f" '{self.name}'. It has already been registered at least once, any" + " changes will not be applied consistently.\n" + "Make sure all imports, decorators, functions, etc. needed to set up" + " the blueprint are done before registering it." + ) + + @setupmethod + def record(self, func: DeferredSetupFunction) -> None: + """Registers a function that is called when the blueprint is + registered on the application. This function is called with the + state as argument as returned by the :meth:`make_setup_state` + method. + """ + self.deferred_functions.append(func) + + @setupmethod + def record_once(self, func: DeferredSetupFunction) -> None: + """Works like :meth:`record` but wraps the function in another + function that will ensure the function is only called once. If the + blueprint is registered a second time on the application, the + function passed is not called. + """ + + def wrapper(state: BlueprintSetupState) -> None: + if state.first_registration: + func(state) + + self.record(update_wrapper(wrapper, func)) + + def make_setup_state( + self, app: App, options: dict[str, t.Any], first_registration: bool = False + ) -> BlueprintSetupState: + """Creates an instance of :meth:`~flask.blueprints.BlueprintSetupState` + object that is later passed to the register callback functions. + Subclasses can override this to return a subclass of the setup state. + """ + return BlueprintSetupState(self, app, options, first_registration) + + @setupmethod + def register_blueprint(self, blueprint: Blueprint, **options: t.Any) -> None: + """Register a :class:`~flask.Blueprint` on this blueprint. Keyword + arguments passed to this method will override the defaults set + on the blueprint. + + .. versionchanged:: 2.0.1 + The ``name`` option can be used to change the (pre-dotted) + name the blueprint is registered with. This allows the same + blueprint to be registered multiple times with unique names + for ``url_for``. + + .. versionadded:: 2.0 + """ + if blueprint is self: + raise ValueError("Cannot register a blueprint on itself") + self._blueprints.append((blueprint, options)) + + def register(self, app: App, options: dict[str, t.Any]) -> None: + """Called by :meth:`Flask.register_blueprint` to register all + views and callbacks registered on the blueprint with the + application. Creates a :class:`.BlueprintSetupState` and calls + each :meth:`record` callback with it. + + :param app: The application this blueprint is being registered + with. + :param options: Keyword arguments forwarded from + :meth:`~Flask.register_blueprint`. + + .. versionchanged:: 2.3 + Nested blueprints now correctly apply subdomains. + + .. versionchanged:: 2.1 + Registering the same blueprint with the same name multiple + times is an error. + + .. versionchanged:: 2.0.1 + Nested blueprints are registered with their dotted name. + This allows different blueprints with the same name to be + nested at different locations. + + .. versionchanged:: 2.0.1 + The ``name`` option can be used to change the (pre-dotted) + name the blueprint is registered with. This allows the same + blueprint to be registered multiple times with unique names + for ``url_for``. + """ + name_prefix = options.get("name_prefix", "") + self_name = options.get("name", self.name) + name = f"{name_prefix}.{self_name}".lstrip(".") + + if name in app.blueprints: + bp_desc = "this" if app.blueprints[name] is self else "a different" + existing_at = f" '{name}'" if self_name != name else "" + + raise ValueError( + f"The name '{self_name}' is already registered for" + f" {bp_desc} blueprint{existing_at}. Use 'name=' to" + f" provide a unique name." + ) + + first_bp_registration = not any(bp is self for bp in app.blueprints.values()) + first_name_registration = name not in app.blueprints + + app.blueprints[name] = self + self._got_registered_once = True + state = self.make_setup_state(app, options, first_bp_registration) + + if self.has_static_folder: + state.add_url_rule( + f"{self.static_url_path}/<path:filename>", + view_func=self.send_static_file, # type: ignore[attr-defined] + endpoint="static", + ) + + # Merge blueprint data into parent. + if first_bp_registration or first_name_registration: + self._merge_blueprint_funcs(app, name) + + for deferred in self.deferred_functions: + deferred(state) + + cli_resolved_group = options.get("cli_group", self.cli_group) + + if self.cli.commands: + if cli_resolved_group is None: + app.cli.commands.update(self.cli.commands) + elif cli_resolved_group is _sentinel: + self.cli.name = name + app.cli.add_command(self.cli) + else: + self.cli.name = cli_resolved_group + app.cli.add_command(self.cli) + + for blueprint, bp_options in self._blueprints: + bp_options = bp_options.copy() + bp_url_prefix = bp_options.get("url_prefix") + bp_subdomain = bp_options.get("subdomain") + + if bp_subdomain is None: + bp_subdomain = blueprint.subdomain + + if state.subdomain is not None and bp_subdomain is not None: + bp_options["subdomain"] = bp_subdomain + "." + state.subdomain + elif bp_subdomain is not None: + bp_options["subdomain"] = bp_subdomain + elif state.subdomain is not None: + bp_options["subdomain"] = state.subdomain + + if bp_url_prefix is None: + bp_url_prefix = blueprint.url_prefix + + if state.url_prefix is not None and bp_url_prefix is not None: + bp_options["url_prefix"] = ( + state.url_prefix.rstrip("/") + "/" + bp_url_prefix.lstrip("/") + ) + elif bp_url_prefix is not None: + bp_options["url_prefix"] = bp_url_prefix + elif state.url_prefix is not None: + bp_options["url_prefix"] = state.url_prefix + + bp_options["name_prefix"] = name + blueprint.register(app, bp_options) + + def _merge_blueprint_funcs(self, app: App, name: str) -> None: + def extend( + bp_dict: dict[ft.AppOrBlueprintKey, list[t.Any]], + parent_dict: dict[ft.AppOrBlueprintKey, list[t.Any]], + ) -> None: + for key, values in bp_dict.items(): + key = name if key is None else f"{name}.{key}" + parent_dict[key].extend(values) + + for key, value in self.error_handler_spec.items(): + key = name if key is None else f"{name}.{key}" + value = defaultdict( + dict, + { + code: {exc_class: func for exc_class, func in code_values.items()} + for code, code_values in value.items() + }, + ) + app.error_handler_spec[key] = value + + for endpoint, func in self.view_functions.items(): + app.view_functions[endpoint] = func + + extend(self.before_request_funcs, app.before_request_funcs) + extend(self.after_request_funcs, app.after_request_funcs) + extend( + self.teardown_request_funcs, + app.teardown_request_funcs, + ) + extend(self.url_default_functions, app.url_default_functions) + extend(self.url_value_preprocessors, app.url_value_preprocessors) + extend(self.template_context_processors, app.template_context_processors) + + @setupmethod + def add_url_rule( + self, + rule: str, + endpoint: str | None = None, + view_func: ft.RouteCallable | None = None, + provide_automatic_options: bool | None = None, + **options: t.Any, + ) -> None: + """Register a URL rule with the blueprint. See :meth:`.Flask.add_url_rule` for + full documentation. + + The URL rule is prefixed with the blueprint's URL prefix. The endpoint name, + used with :func:`url_for`, is prefixed with the blueprint's name. + """ + if endpoint and "." in endpoint: + raise ValueError("'endpoint' may not contain a dot '.' character.") + + if view_func and hasattr(view_func, "__name__") and "." in view_func.__name__: + raise ValueError("'view_func' name may not contain a dot '.' character.") + + self.record( + lambda s: s.add_url_rule( + rule, + endpoint, + view_func, + provide_automatic_options=provide_automatic_options, + **options, + ) + ) + + @setupmethod + def app_template_filter( + self, name: str | None = None + ) -> t.Callable[[T_template_filter], T_template_filter]: + """Register a template filter, available in any template rendered by the + application. Equivalent to :meth:`.Flask.template_filter`. + + :param name: the optional name of the filter, otherwise the + function name will be used. + """ + + def decorator(f: T_template_filter) -> T_template_filter: + self.add_app_template_filter(f, name=name) + return f + + return decorator + + @setupmethod + def add_app_template_filter( + self, f: ft.TemplateFilterCallable, name: str | None = None + ) -> None: + """Register a template filter, available in any template rendered by the + application. Works like the :meth:`app_template_filter` decorator. Equivalent to + :meth:`.Flask.add_template_filter`. + + :param name: the optional name of the filter, otherwise the + function name will be used. + """ + + def register_template(state: BlueprintSetupState) -> None: + state.app.jinja_env.filters[name or f.__name__] = f + + self.record_once(register_template) + + @setupmethod + def app_template_test( + self, name: str | None = None + ) -> t.Callable[[T_template_test], T_template_test]: + """Register a template test, available in any template rendered by the + application. Equivalent to :meth:`.Flask.template_test`. + + .. versionadded:: 0.10 + + :param name: the optional name of the test, otherwise the + function name will be used. + """ + + def decorator(f: T_template_test) -> T_template_test: + self.add_app_template_test(f, name=name) + return f + + return decorator + + @setupmethod + def add_app_template_test( + self, f: ft.TemplateTestCallable, name: str | None = None + ) -> None: + """Register a template test, available in any template rendered by the + application. Works like the :meth:`app_template_test` decorator. Equivalent to + :meth:`.Flask.add_template_test`. + + .. versionadded:: 0.10 + + :param name: the optional name of the test, otherwise the + function name will be used. + """ + + def register_template(state: BlueprintSetupState) -> None: + state.app.jinja_env.tests[name or f.__name__] = f + + self.record_once(register_template) + + @setupmethod + def app_template_global( + self, name: str | None = None + ) -> t.Callable[[T_template_global], T_template_global]: + """Register a template global, available in any template rendered by the + application. Equivalent to :meth:`.Flask.template_global`. + + .. versionadded:: 0.10 + + :param name: the optional name of the global, otherwise the + function name will be used. + """ + + def decorator(f: T_template_global) -> T_template_global: + self.add_app_template_global(f, name=name) + return f + + return decorator + + @setupmethod + def add_app_template_global( + self, f: ft.TemplateGlobalCallable, name: str | None = None + ) -> None: + """Register a template global, available in any template rendered by the + application. Works like the :meth:`app_template_global` decorator. Equivalent to + :meth:`.Flask.add_template_global`. + + .. versionadded:: 0.10 + + :param name: the optional name of the global, otherwise the + function name will be used. + """ + + def register_template(state: BlueprintSetupState) -> None: + state.app.jinja_env.globals[name or f.__name__] = f + + self.record_once(register_template) + + @setupmethod + def before_app_request(self, f: T_before_request) -> T_before_request: + """Like :meth:`before_request`, but before every request, not only those handled + by the blueprint. Equivalent to :meth:`.Flask.before_request`. + """ + self.record_once( + lambda s: s.app.before_request_funcs.setdefault(None, []).append(f) + ) + return f + + @setupmethod + def after_app_request(self, f: T_after_request) -> T_after_request: + """Like :meth:`after_request`, but after every request, not only those handled + by the blueprint. Equivalent to :meth:`.Flask.after_request`. + """ + self.record_once( + lambda s: s.app.after_request_funcs.setdefault(None, []).append(f) + ) + return f + + @setupmethod + def teardown_app_request(self, f: T_teardown) -> T_teardown: + """Like :meth:`teardown_request`, but after every request, not only those + handled by the blueprint. Equivalent to :meth:`.Flask.teardown_request`. + """ + self.record_once( + lambda s: s.app.teardown_request_funcs.setdefault(None, []).append(f) + ) + return f + + @setupmethod + def app_context_processor( + self, f: T_template_context_processor + ) -> T_template_context_processor: + """Like :meth:`context_processor`, but for templates rendered by every view, not + only by the blueprint. Equivalent to :meth:`.Flask.context_processor`. + """ + self.record_once( + lambda s: s.app.template_context_processors.setdefault(None, []).append(f) + ) + return f + + @setupmethod + def app_errorhandler( + self, code: type[Exception] | int + ) -> t.Callable[[T_error_handler], T_error_handler]: + """Like :meth:`errorhandler`, but for every request, not only those handled by + the blueprint. Equivalent to :meth:`.Flask.errorhandler`. + """ + + def decorator(f: T_error_handler) -> T_error_handler: + def from_blueprint(state: BlueprintSetupState) -> None: + state.app.errorhandler(code)(f) + + self.record_once(from_blueprint) + return f + + return decorator + + @setupmethod + def app_url_value_preprocessor( + self, f: T_url_value_preprocessor + ) -> T_url_value_preprocessor: + """Like :meth:`url_value_preprocessor`, but for every request, not only those + handled by the blueprint. Equivalent to :meth:`.Flask.url_value_preprocessor`. + """ + self.record_once( + lambda s: s.app.url_value_preprocessors.setdefault(None, []).append(f) + ) + return f + + @setupmethod + def app_url_defaults(self, f: T_url_defaults) -> T_url_defaults: + """Like :meth:`url_defaults`, but for every request, not only those handled by + the blueprint. Equivalent to :meth:`.Flask.url_defaults`. + """ + self.record_once( + lambda s: s.app.url_default_functions.setdefault(None, []).append(f) + ) + return f |