mirror of
https://github.com/aiogram/aiogram.git
synced 2025-12-12 10:11:52 +00:00
57 lines
2.2 KiB
ReStructuredText
57 lines
2.2 KiB
ReStructuredText
|
####################
|
||
|
|
Dependency injection
|
||
|
|
####################
|
||
|
|
|
||
|
|
Dependency injection is a programming technique that makes a class independent of its dependencies. It achieves that by decoupling the usage of an object from its creation. This helps you to follow `SOLID's <https://en.wikipedia.org/wiki/SOLID>`_ dependency inversion and single responsibility principles.
|
||
|
|
|
||
|
|
|
||
|
|
How it works in aiogram
|
||
|
|
=======================
|
||
|
|
For each update :class:`Dispatcher` passes handling context data. Filters and middleware can also make changes to the context.
|
||
|
|
|
||
|
|
To access contextual data you should specify corresponding keyword parameter in handler or filter. For example, to get :class:`FSMContext` we do it like that:
|
||
|
|
|
||
|
|
.. code-block:: python
|
||
|
|
@router.message(ProfileCompletion.add_photo, F.photo)
|
||
|
|
async def add_photo(
|
||
|
|
message: types.Message, bot: Bot, state: FSMContext
|
||
|
|
) -> Any:
|
||
|
|
... # do something with photo
|
||
|
|
|
||
|
|
|
||
|
|
Injecting own dependencies
|
||
|
|
==========================
|
||
|
|
|
||
|
|
Aiogram provides several ways to complement / modify contextual data.
|
||
|
|
|
||
|
|
The first and easiest way is to simply specify the named arguments in :class:`Dispatcher` initialization, polling start methods or :class:`SimpleRequestHandler` initialization if you use webhooks.
|
||
|
|
|
||
|
|
.. code-block:: python
|
||
|
|
async def main() -> None:
|
||
|
|
dp = Dispatcher(..., foo=42)
|
||
|
|
return await dp.start_polling(
|
||
|
|
bot, allowed_updates=dp.resolve_used_update_types(), bar="Bazz"
|
||
|
|
)
|
||
|
|
Analogy for webhook:
|
||
|
|
|
||
|
|
.. code-block:: python
|
||
|
|
async def main() -> None:
|
||
|
|
dp = Dispatcher(..., foo=42)
|
||
|
|
handler = SimpleRequestHandler(dispatcher=dp, bot=bot, bar="Bazz")
|
||
|
|
... # starting webhook
|
||
|
|
:class:`Dispatcher`'s workflow data also can be supplemented by setting values as in a dictionary:
|
||
|
|
|
||
|
|
.. code-block:: python
|
||
|
|
dp = Dispatcher(...)
|
||
|
|
dp["eggs"] = Spam()
|
||
|
|
The middlewares updates the context quite often.
|
||
|
|
You can read more about them on this page:
|
||
|
|
|
||
|
|
- `Middlewares <middlewares.html>`__
|
||
|
|
|
||
|
|
The last way is to return a dictionary from the filter:
|
||
|
|
|
||
|
|
.. literalinclude:: ../../../examples/context_addition_from_filter.py
|
||
|
|
|
||
|
|
...or using MagicFilter with :code:`as_()` method. (`Read more <filters/magic_filters.html#get-filter-result-as-handler-argument>`__)
|