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📝 Update includes in docs/en/docs/advanced/events.md #12604

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alejsdev merged 3 commits into from
Oct 28, 2024
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📝 Update includes in docs/en/docs/advanced/events.md #12604

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Update includes in docs/en/docs/advanced/events.md
salmantec Oct 27, 2024
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Update includes
salmantec Oct 27, 2024
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Removed extra empty line
salmantec Oct 27, 2024
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24 changes: 6 additions & 18 deletions docs/en/docs/advanced/events.md
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Expand Up @@ -30,9 +30,7 @@ Let's start with an example and then see it in detail.

We create an async function `lifespan()` with `yield` like this:

```Python hl_lines="16 19"
{!../../docs_src/events/tutorial003.py!}
```
{* ../../docs_src/events/tutorial003.py hl[16,19] *}

Here we are simulating the expensive *startup* operation of loading the model by putting the (fake) model function in the dictionary with machine learning models before the `yield`. This code will be executed **before** the application **starts taking requests**, during the *startup*.

Expand All @@ -50,9 +48,7 @@ Maybe you need to start a new version, or you just got tired of running it. 🤷

The first thing to notice, is that we are defining an async function with `yield`. This is very similar to Dependencies with `yield`.

```Python hl_lines="14-19"
{!../../docs_src/events/tutorial003.py!}
```
{* ../../docs_src/events/tutorial003.py hl[14:19] *}

The first part of the function, before the `yield`, will be executed **before** the application starts.

Expand All @@ -64,9 +60,7 @@ If you check, the function is decorated with an `@asynccontextmanager`.

That converts the function into something called an "**async context manager**".

```Python hl_lines="1 13"
{!../../docs_src/events/tutorial003.py!}
```
{* ../../docs_src/events/tutorial003.py hl[1,13] *}

A **context manager** in Python is something that you can use in a `with` statement, for example, `open()` can be used as a context manager:

Expand All @@ -88,9 +82,7 @@ In our code example above, we don't use it directly, but we pass it to FastAPI f

The `lifespan` parameter of the `FastAPI` app takes an **async context manager**, so we can pass our new `lifespan` async context manager to it.

```Python hl_lines="22"
{!../../docs_src/events/tutorial003.py!}
```
{* ../../docs_src/events/tutorial003.py hl[22] *}

## Alternative Events (deprecated)

Expand All @@ -112,9 +104,7 @@ These functions can be declared with `async def` or normal `def`.

To add a function that should be run before the application starts, declare it with the event `"startup"`:

```Python hl_lines="8"
{!../../docs_src/events/tutorial001.py!}
```
{* ../../docs_src/events/tutorial001.py hl[8] *}

In this case, the `startup` event handler function will initialize the items "database" (just a `dict`) with some values.

Expand All @@ -126,9 +116,7 @@ And your application won't start receiving requests until all the `startup` even

To add a function that should be run when the application is shutting down, declare it with the event `"shutdown"`:

```Python hl_lines="6"
{!../../docs_src/events/tutorial002.py!}
```
{* ../../docs_src/events/tutorial002.py hl[6] *}

Here, the `shutdown` event handler function will write a text line `"Application shutdown"` to a file `log.txt`.

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